December 1985 - Australian Association Of Musculoskeletal Medicine

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1 ISSN 1324-5627 Australasian Musculoskeletal Medicine a Mechanisms of complex pain syndromes a AFMM standards: Lumbar medial branch blocks a AFMM standards: Cervical medial branch blocks a Muscle cramp a Chronic Achilles tendinosis a Articular cartilage defects a Stiff painful shoulder Vol. 6 No. 2 November 2001 Registered by Australia Post Publication No. NAW 6362 AAMM Website: www.aamm.asn.au

2 Australasian Musculoskeletal Medicine November 2001 Australian Association of New Zealand Association of Musculoskeletal Medicine Office Bearers 1999 - 2001 Musculoskeletal Medicine Office Bearers 2000 - 2001 Contents President President Editorial ....................................... 3 Dr Steve Jensen MB BS, Grad Dip Dr James Watt From AAMM President ... ........... 4 Musc Med 308 Lake Rd, Takapuna, Auckland 5 Stanlake St Ph: + 64 9 489 5059 From NZAMM President .. .......... 6 Footscray Vic 3011 Fax: + 64 9 486 4937 Ph: +61 3 93185233 [email protected] Letters to the editor .................... 7 Fax: +61 3 93186630 Secretary Mechanisms of complex pain syndromes .......................... 8 Vice President Dr John Robinson Dr Scott Masters MB BS, FRACGP, 256 Papanui Rd, Christchurch AFMM Practice Standards and FAFMM Ph: + 64 3 355 0342 Protocols: Lumbar medial Caloundra Medical Centre Fax: + 64 3 355 7071 branch blocks ........................... 23 39 Minchinton St, Caloundra, Q 4551 [email protected] Ph: +61 7 54911144 AFMM Practice Standards and Protocols: Cervical medial Fax: +61 7 54911253 Treasurer branch blocks ........................... 41 Clemens Franzmayr Honorary Secretary 256 Papanui Rd, Christchurch Muscle cramp ........................... 62 Dr Michael Yelland MB BS, FRACGP, Ph: + 64 3 355 7080 FAFMM, Grad Dip Musc Med Fax: + 64 3 355 7071 Management of chronic Achilles tendinosis .................... 65 64 Wirraway Pde, Inala, Q 4077 Ph: +61 7 32755444 Past President Autologous chondrocyte Fax: +61 7 32789987 Dr Mark Johnston implantation in the management 16 Moana Ave, Orewa of articular cartilage defects ..... 72 Honorary Treasurer Ph: + 64 9 426 5436 Dr Derek Davey MB BS, D Obst, The stiff painful shoulder .......... 78 RCOG, Grad Dip Occ H, Grad Dip Academic Co-ordinator Thoughts on soft tissue pain .... 81 Musc Med, FAFMM Dr Jim Borowczyk 29 Craigie Rd, Newtown Vic 3220 256 Papanui Rd, Christchurch Journal abstracts ...................... 86 Ph: +61 3 52223677 Ph: + 64 3 355 0342 Fax: +61 3 52213104 Fax:+ 64 3 355 7071 FIMM update ............................ 89 Educational Activities ................ 92 Committee Members Committee Members Dr Robert Gassin MB BS, FAFMM, Dr Peter Airey, Christchurch Management of lateral elbow Grad Dip Musc Med Ph: + 64 3 352 6882 pain ........................................... 95 Cranbourne North, Vic 3977 Dr Steve Bentley, Dunedin Ph: +61 3 59956999 Ph: +64 3 474 1899 Fax: +61 3 59956700 Dr Gary Collinson, Auckland Ph: + 64 9 624 1024 Australasian Musculoskeletal Medicine Dr Geoff Harding MB BS, FAFMM, Dr Alastair Fraser, Taupo is published by the Australian Associa- Grad Dip Musc Med (immediate past Ph: + 64 7 378 4080 tion of Musculoskeletal Medicine for president) Dr David Jacks, Havelock North medical practitioners interested in the Sandgate, Q Ph: + 64 6 877 7555 aetiology and management of muscu- loskeletal disorders. Opinions expressed Ph: +61 7 32695522 Dr Andrew Moynagh are those of the authors and not neces- Fax: +61 7 38693288 Ph: + 64 4 388 7018 sarily those of the editor or the Associa- Dr Peter McKenzie tion. Editorial comment may reflect the Dr Des Schimeld MB BS, Grad Dip Ph: + 64 3 541 8911 opinions of the editor alone. Contribu- tions on any relevant topic are welcome Musc Med, BSc(Hons) Dr Grant Thomson, Whangarei for submission to the editor, Dr Scott Dulwich, SA 5065 Ph: + 64 9 435 0692 Masters, Caloundra Medical Centre, Ph: +61 8 83612769 Suite 4 Trinity House, 39 Minchinton St., Caloundra Qld 4551. Phone: + 61 7 5491 1144(w), +61 7 5443 9475. Fax: + Dr Phil Watson BSc, MB, ChB, 61 7 5491 1253(w). FRACGP, Dip Obst, Dip Mus Med, Email: [email protected] CIME Sunnybank, Q 4109 Ph: +61 7 33457117 Fax: +61 7 3216 9052 AAMM Website: www.aamm.asn.au 2

3 Australasian Musculoskeletal Medicine November 2001 Editorial Dr Scott Masters T his edition of the journal is musculoskeletal. they should be directed to the presi- a landmark publication. We Geoffrey Harding and I have also dent or one of the committee mem- have published the first had feature articles published in bers for further help. guidelines in the world on medial successive Medical Observer is- Recently two new members have branch blocks and radiofrequency sues. There seems to be a demand joined the editorial team. Dr David ablation to the lumbar and cervical out in the medical literature for in- Roselt and Dr Esther Langenegger. spine. Even more special is that formed critical analysis and prag- Both have over 10 years experi- much of the research into these matic summaries on musculoskel- ence in postgraduate study and techniques was forged here in Aus- etal topics. In the past, much of the both are fellows of the AFMM. David tralia. Thus it seems more than written material in the journals or hails from Bundaberg and has a appropriate that they are released the verbal offerings at sponsored strong background in medical acu- in Australasian Musculoskeletal meetings has been dominated by puncture. Esther works in Albury/ Medicine under the Australasian non-critical comment on problems Wodonga in a pain clinic and tutors Faculty of Musculoskeletal banner. that present to tertiary care rather for the Otago musculoskeletal medi- It was also rewarding to see other than primary care. The tide seems cine diploma course. Their profes- musculoskeletal luminaries having to be slowly turning now as editors sional expertise will enhance the work published in the general prac- of medical publications start to seek quality of the journal well into the tice arena. Our new president Steve out material of more relevance to rest of this decade. Jensen wrote a timely article for both primary care doctors and pa- Finally, Id like to pass on my Australian Family Physician (9/01) tients. appreciation to the outgoing com- on musculoskeletal causes of chest We need to take this opportunity mittee members for all their hard pain. In the same journal Michael to avail these people of the AAMM work over the last two years. It is Yelland, research guru, published database and encourage its dis- heart warming and inspiring to see his original research on spinal signs semination. Members should notify the dedication these members de- in back, chest, and abdominal pain. their divisions and local medical vote to the cause. All for the love, Recommended reading for anybody associations about our resource. If not for the money. Hats off. with a passing interest in matters they want informed comment, then Scott Masters 3

4 Australasian Musculoskeletal Medicine November 2001 From the AAMM President, Dr Steve Jensen A t the Hunter Valley Annual scheme, for which remuneration will need to be cognisant of the limitations Scientific Meeting held in July be well above the current GP rate. in terms of reliability and validity of our 2001 I had the honour and On contemplating this report, I re- physical examination, and other facets privilege to be elected to the office of flected on how I came to be involved in (no pun intended) of the evidence President of AAMM. I perused my old AAMM. Like many members my intro- base. But even just examining some- copies of the Green Journal, or the duction to matters musculoskeletal was one confidently can be therapeutic. Bulletin as it was known way back via the course run by John Murtagh Thus, one of my aims of office is to when, and found the following list of ex- and Clive Kenna. I first attended one of expand on the work started by Murtagh/ presidents: Geoff Harding, Vic Wilk, these courses because I had moved Kenna and admirably continued by the Norm Broadhurst, David Vivian, and from the protected environment of likes of the Quattro Amigos in Queens- Nikolai Bogduk. If you look at this list, hospital practice to the frontline of land, and Norm Broadhurst in South there is a plethora of talented and general practice. Confronting me day Australia and take our message and dedicated people to whom we are all in and day out were numerous people skills to general practitioners through- indebted because, in their own way, with musculoskeletal pain, and par- out the country. We need to find a way they have all helped musculoskeletal ticularly low back pain. Published fig- to get our foot in the door of institutions medicine move from the realms of ures suggest that around 20% of GP like the GP divisions in order to achieve alternative medicine to a position consultations are for musculoskeletal this. So if there are any divisional whereby it is a force in mainstream problems, while low back pain alone leaders out there, please contact any medicine. There is still a lot of turf to till, represents about 5%. My undergradu- member of the committee and we will but I perceive that we now have a solid ate and postgraduate training, includ- endeavour to run a workshop in your plot of land to develop. Indeed, when I ing that run by RACGP, had failed to area. If anyone has any helpful hints in reflect on those who have held this provide me with any skills to assess or enabling us to open these and any office before me, and what they have examine these patients, let alone man- other doors, please forward them. done for musculoskeletal medicine in age these poor unsuspecting individu- The rural doctors, I believe are a Australasia, to say that I have some als!! The advert, and I forget where I special needs group, given that they hard acts to follow is the proverbial came across it, implied that I would be often do not have ready access to understatement. Nonetheless, I will do able to learn all of this in 2 weekends! paramedical services. We should cer- my best to aspire somewhere towards Sounded too good to be true! And tainly be targeting that group to up- their heady heights. although it did not provide me with a grade their skills in order to better serve Increasing acceptance of muscu- panacea, it did plant a seed which grew the people of the rural and remote loskeletal medicine by higher authori- into a small forest until it consumed communities. ties, at least in the Workcover environ- over 60% of my general practice con- So this is also a call to all of you ment, is perhaps best demonstrated in sultations. With the help of a Flinders teachers out there. Even if you havent Victoria, where those of us with faculty Diploma, I ultimately decided to take been involved in teaching before! If fellowships are recognised as special- the plunge and move into full time msk you have been practising musculoskel- ists in our own right. Some of us have medicine practice. I have absolutely etal medicine for a number of years, been invited to be members of Medical no regrets apart from the fact that, if then you most certainly have many Panels, the final arbiter of disputed anything, I am too busy. Nearly all of skills to pass on to your GP colleagues. Workcover and transport accident my work is referred from either GPs or So let us know who and where you are claims. Most recently I have been other medical specialists, with a smat- and we can try to involve you in teach- invited to sit on a clinical advisory tering from paramedicaI practitioners. ing. It is a most rewarding experience. group for the Victorian Workcover I read this as a sign that there is a huge And I for one have found that it is a very Authority, which is trying to implement need in matters musculoskeletal that is sobering experience in that it is a sure a new model for management of sprain not currently being met by established way to find out how well you know a and strain injuries. I hope to report to groups. subject. you on the outcome of this initiative in But AAMM is not for specialists like There are often unexpected benefits the not too distant future. Suffice to say me. That is where the Faculty fits in. from teaching. The Quality Patient that early signs are that, if it becomes AAMM is for primary care practition- Education (QPE) CD enclosed with implemented, there will be openings ers. I believe AAMM needs to continue this issue of the journal was devised for many interested musculoskeletal to disseminate the skills and knowl- and produced by Dr Ronnie Moule, practitioners, not only those with fel- edge that collectively our organisation who was one of my students at the lowships, to be actively involved in the has in order to meet this need. Yes, we Swinburne University of Technology, 4

5 Australasian Musculoskeletal Medicine November 2001 From the AAMM President, Dr Steve Jensen Graduate School of Integrative Medi- cine. Having been bitten by the muscu- loskeletal bug, Ronnie conceived and developed this CD herself, and I think you will agree that the finished product will be a very useful tool on every GPs desk. As a service to members, the committee of AAMM has negotiated a very heavily discounted price for this CD so that it may be distributed to all members at no cost to them. The recommended retail price of this CD is almost half of your annual subscrip- tion. Of course one of the highlights every year is the annual scientific meeting of AAMM. As I write this, the next meet- ing, to be held in Melbourne on the weekend of October 20 2002, is al- ready being planned. The conference committee, and Vic Wilk in particular, is already working towards making this the best conference ever in terms of the scientific content, practicality of the workshops and entertainment within the conference framework. This time of year in Melbourne is a very busy but vibrant one with the spring horse rac- ing carnival, as well as the Melbourne Festival for all of you culture buffs, and also the Melbourne Fringe Festival for all of you alternative bods out there. So I suggest that you write this date in your diary now. Hope to see you there, if not before- hand. 5

6 Australasian Musculoskeletal Medicine November 2001 From the NZAMM President, Dr James Watt Coming of Age M usculoskeletal medicine has There is little support in the literature from the chronic cases those whose come of age in New Zea- as yet for much of what we do. Articles symptoms have been present for longer land with achievement of continue to be published showing poor than three months. It is this group vocational registration, inclusion on intra-, and very poor inter-observer, which places the great demand on the Specialist Register and conse- reliability in clinical tests, which are society both in lost productivity and in quent change in funding, and accept- often used for diagnosis. There is seeking relief from their chronic pain ance by most insurance companies considerable nihilism regarding the and impairment. It is also this group for payment of specialist fees. We worth both of such tests and of exami- that the literature shows has a very have a contract with ACC for ordering nation. A series of recent articles in small prospect of recovery. Thus, it is examinations requiring specialist ap- journals of manual therapy1-6 attest to this group that the skills of a specialist proval as well as an assessment con- the lack of both inter- and intra-ob- musculoskeletal physician are most tract. server reliability over a number of likely to benefit. The broad base of What has led to this recognition? It different tests performed often by very knowledge and skills, ranging from has involved persistent hard work in a experienced practitioners. There are anatomy and biomechanics, including number of key areas. Initially we devel- occasional articles7,8 which demon- physical modalities and rehabilitation, oped an educational program designed strate a degree of concordance, but to pain management using drugs, in- to promote musculoskeletal medicine these mainly test fairly coarse meas- jection techniques and blocks, offer amongst GPs. This started in the 1970s ures. the greatest prospect of relief and when an enthusiastic group arranged There is some evidence that a so- recovery in the large proportion of courses taught by Danish musculoskel- phisticated measuring instrument, the cases unlikely to be helped by surgery. etal physicians, Fossgreen and Pripp, lumbar motion monitor, could be used It is imperative that we all keep records and later, Rasmussen. Subsequently to differentiate between those with back and review our patients progress as Barrie Tait arranged for renowned pain and those without.9,10 (While some required by our re-accreditation pro- American osteopath, Philip Greenman, may prefer merely to ask the question, gram, and that we then, either individu- to visit for a semester and advise on the at least this shows that there is a ally or in groups, publish our results. It establishment of the Otago Diploma of quantifiable difference.) is our performance by which we will be Musculoskeletal Medicine. How then, do manual therapists ex- judged. If we demonstrate the benefit Then in the mid 1980s Jiri Dvorak, a pect to diagnose, let alone treat mus- we offer, our specialty will flourish. professor of neurology from Zurich, culoskeletal problems? This, presum- worked with a group who established ably, is not achievable by random References a series of teaching courses and manu- manipulation. 1. Leboeuf-Yde C, Kyvik KO. Is it als which were used for teaching the Despite the bleak picture painted by possible to differentiate people with or practical part of the Otago diploma. much of the literature, there are a large without low-back pain on the basis of The group involved at this stage number of therapists who have reputa- tests of lumbopelvic dysfunction. JMTP developed a close working arrange- tions that cause patients to seek, and 2000; 23:160-67. ment with Australian counterparts (such be willing to pay for, their help. The 2. Hestboek L, Leboeuf-Yde C. Are that one of our number emigrated), possibility of accuracy of clinical diag- chiropractic tests for the lumbo-pelvic working initially on a syllabus and later nosis, was shown by Jull11 in a paper spine reliable and valid? A systematic a Fellowship with its associated exam. which was later held to be open to critical literature review. JMTP 2000; This step has proven critical in accept- scientific criticism. 23: 258-75. ance of specialist recognition as it The literature shows that manipula- 3. Hawk C, Phongpuha C, Bleecker J, established a standard by which Fel- tive therapy is helpful at least in acute Swank L, Lopez D, Rubley T. Prelimi- lows are judged. cases, and the popularity of manual nary study of reliability of assessment Now that we have achieved this rec- therapists suggests that they provide procedures for indications for chiro- ognition, we are acutely aware of the some benefit (even though natural his- practic adjustments of the lumbar spine. need to provide evidence of our useful- tory is a very handy ally). In order to JMTP 1999; 22: 382-89. ness and cost effectiveness in order to achieve this benefit, therapy needs to 4. Levangie PK. Four clinical tests of further the professional recognition by be appropriate both in form and direc- sacroiliac joint dysfunction: the asso- colleagues and funders alike. Con- tion. This at least requires an educated ciation of test results with innominate sumers already seem satisfied overall guess. torsion among patients with and with- (as judged by attendance and satis- The major cost to society, both in out low back pain. faction questionnaires). social as well as fiscal terms, comes 5. Vincent-Smith B, Gibbons P. Inter- 6

7 Australasian Musculoskeletal Medicine November 2001 Letters to the Editor examiner and intra-examiner reliability Glucosamine cause all Australian drug manufactur- of the standing flexion test. J Man Ther Dear Editor ers (unlike in the US) must comply with 1999; 4: 87-93. Thanks very much for your review of the Code of Good Manufacturing Prac- 6. Van der Wurff P, Meyne W, glucosamine. I think you have cer- tice, it is unlikely that labelling discrep- Hagmeijer RHM. Clinical tests of the tainly covered the main issues involved ancies will occur in our country. You sacroiliac joint: a systematic methodo- comprehensively. could make that comment about prod- logical review. Part2: validity. Man Ther Some observations on the topic are ucts that are obtained from overseas. 2000; 5: 89-96. as follows: However, our products are regulated 7. Razmjou H, Kramer J, Yamada R. 1. Unfortunately, there is no evi- as foods not drugs. But all therapeutic Intertester reliability of the McKenzie dence that glucosamine sulphate and goods in Australia - whether treatment evaluation in assessing patients with glucosamine hydrochloride are or over-the-counter or complementary mechanical low-back pain. J Orthop bioequivalent. Yet I think it will be the medicines - must be either listed or Sports Phys Ther 2000; 30: 368-89. hydrochloride salt the majority of Aus- registered and made according to the 8. Cibulka MT, Koldehoff R. Clinical tralian patients will be taking. Even Code of GMP or they have their manu- usefulness of a cluster of sacroiliac though there is reasonable evidence facturing licence withdrawn. joint tests in patients with and without that glucosamine hydrochloride 4. With respect to safety, you low back pain. J Orthop Sports Phys is absorbed, its the sulphate salt about should contact ADRAC for a print out Ther 1999; 29: 83-92. which most of the fabulous evidence of the adverse reactions theyve had 9. MarrasWS, Ferguson SA, Gupta P, has been constructed. So, can we reported to glucosamine salts. Weve Bose S, Parnianpour M, Kim J, Crowell really - in all good conscience - apply had reported to our Medication Helpline RR. The quantification of low back the same conclusions from one to the rashes, urticaria, nausea, and so on. disorder using motion measures. Spine other? Boring and common though those re- 1999; 24: 2091-2100. 2. Perhaps it would help physi- actions are, they still show that adverse 10. Marras S, Lewis KEK, Ferguson cians insight into the complementary reactions can occur and glucosamine SA,Parnianpour M. Impairment mag- medicine industry if you told them how is not benign. (I understand that the nification during dynamic trunk mo- glucosamine sulphate is a patented rigour of those reports is less than tions. Spine 2000; 25: 587-95. salt and thats why one manufacturer is perfect, but thats the nature of 11. Jull G, Bogduk N, Marsland A. The behind so much of the evidence (Rotta postmarketing surveillance.) accuracy of manual diagnosis for cer- Pharmaceuticals), and thats also why 5. I think there are more data for vical zygapophyseal joint pain syn- you are likely to see other salts, like the this drug than some of the medicines dromes. Med J Aust 1988; 148: 233- hydrochloride, being marketed, riding that get on the PBS, e.g., Zyban. 36. on the sulphates coat-tails. Some peo- ple believe that the sulphate salt is Geraldine Moses, B Pharm, Postgrad superior because it provides sulphate DipClinPharm groups that bind glycosaminoglycan Mater Pharmacy Services molecules together. Mater Misericordiae Hospitals 3. I dont think its quite accurate to South Brisbane 4101 say (on page 2) that In Australia there is only one TGA approved glucosamine preparation. There is only one glucosamine preparation which car- ries an AUST R number - and it hap- pens to be glucosamine as hydrochlo- ride. Nutrasenses product Arthro-Aid carries an AUST R number, but that does not mean that it is approved by TGA. It means it is a registered prod- uct, as opposed to listed. This is not to be confused with prescription only products for whom the TGA approves indications . They wouldnt have done that with Arthro-Aid. Incidently, be- 7

8 Australasian Musculoskeletal Medicine November 2001 Mechanisms of Complex Regional Pain Syndromes by Nikolai Bogduk, Newcastle Bone and Joint Institute S ome patients who suffer an Sudomotor changes include exces- This interpretation, however, ignores injury to a peripheral nerve, sive sweating or dryness of the af- the essential meaning of allodynia, and some patients who suffer fected part. which is that the stimulus that evokes a relatively trivial musculoskeletal in- Temperature changes mean warm- pain is qualitatively, not quantitatively, jury, develop a bizarre and seemingly ing or cooling of the affected part. different from those that normally evoke unique pain syndrome. In its most Trophic changes include keratosis, pain. The cardinal example is brushing florid state this syndrome is character- brittle nails, hair loss and brawny the skin, i.e., a mechanical stimulus ised by the following: induration of subcutaneous tissues. that is delivered tangential to the skin Pain Motor impairment includes, muscle surface and which does not involve Hyperalgesia spasm and contracture of muscles pressure and deformation of the skin. Allodynia each of which resist and interfere with This type of stimulus never evokes pain Vasomotor, sudomotor and tem- voluntary movement. under normal conditions, regardless perature changes Osteoporosis means elution of cal- of its magnitude. Trophic changes in the skin cium from bones ostensibly because Confusion arises when touch per- Motor impairment of increased osseous blood flow. pendicular to the skin surface is used Osteoporosis. There is debate, confusion and con- as the stimulus. Touch involves pres- troversy concerning the distinction sure, and pressure of sufficient mag- A further feature is that the symp- between hyperalgesia and allodynia. nitude can under normal conditions be toms and signs seem disproportionate Some regard the two as complemen- painful. A shift to the left of the re- in severity to the nature of the precipi- tary aspects of the same phenomenon sponse characteristics of high thresh- tating injury, and occur in a region and mechanism, i.e., a shift to the left old mechanoreceptors would render considerably larger than the one af- of the response curve of sensory them low threshold mechanoreceptors. fected by the original injury. Thus, in nerves2 (Fig. 1). Under these condi- However, in that event, the nature of the the case of a nerve injury, the changes tions, stimuli of an intensity that nor- modality involved does not change. occur outside the territory innervated mally would be painful are perceived Receptors normally capable of being by the affected nerve. In the case of a as more painful than usual. This con- nociceptive are simply rendered more musculoskeletal injury, the changes stitutes hyperalgesia. Stimuli of sensitive. In contrast, when strictly affect anatomical regions beyond that intensities that would normally not be defined, allodynia requires a switch in of the injured part. More curiously, the painful become painful. This consti- the modality. same symptoms can develop after vis- tutes allodynia. ceral injuries (e.g., myocardial infarc- tion) or central nervous system injury (e.g., stroke) and be manifest in a limb that is remote from the site of injury. The pain in question is an unpleasant sensory experience but has no unique or singular quality. In some cases it may be burning in quality; in others it may be deep and aching. It may be dyseasthetic; it may be spontaneous or present only when evoked by palpa- tion of the affected part. Hyperalgesia is an exaggerated or increased response to a stimulus that is normally painful.1 Allodynia (meaning foreign energy) is pain evoked by a stimulus that nor- mally does not produce pain. Figure 1. A definition of hyperalgesia and allodynia in terms of a shift to the left of the Vasomotor changes include vasodi- response curve of a sensory neurone. Under normal conditions the neuron is activated by lation or vasoconstriction manifest re- a stimulus intensity that constitutes a normal threshold for nociception. After injury the spectively as reddening and swelling response curve shifts to the left. Allodynia is the pain evoked by stimuli of intensity less or cyanosis of the affected part. than normal threshold. Hyperalgesia is the greater response to stimuli of an intensity that normally would be painful. 8

9 Australasian Musculoskeletal Medicine November 2001 Mechanisms of Complex Regional Pain Syndromes For such reasons some authorities3 Historical Perspective have objected to allodynia being de- In the past, patients presenting with a constellation of neurologic, vasomotor fined on the basis of a shift to the left. and trophic features attracted diagnostic labels7 that: They prefer hyperalgesia to refer to Example the increased sensitivity of (normally) Described the region affected Shoulder-hand syndrome nociceptive afferents. On the other hand, Price et al4 distinguish two types Described the circumstances of onset Post-traumatic pain syndrome of allodynia. One they describe as low- Post-infarctional scelero dystrophy threshold A>allodynia, which is evoked by gentle brushing with a cotton swab. Reflected one or more of the Post-traumatic spreading neuralgia The other they describe as high thresh- component features Post-traumatic painful arthrosis old allodynia, which is evoked not by Chronic traumatic oedema gentle stimuli but by intense static Post-traumatic oedema stimuli, like pressure, that normally are Acute atrophy of bone not painful. The latter would be what Peripheral acute trophoneurosis Campbell3 refers to as hyperalgesia. Traumatic angiospasm Others5,6 recognise similar distinctions. Post-traumatic osteoporosis They consider brushing to be a dy- Traumatic vasospasm namic (moving) stimulus, and refer to Reflex neurovascular dystrophy pain evoked by such stimuli as brush- evoked allodynia or dynamic allodynia. Implied the mechanism Sympathetic reflex dystrophy Pain evoked by static pressure they Two terms that arose into most com- about 2-5% of such nerve injuries. refer to as static hyperalgesia. mon usage were causalgia - meaning The danger of misusing the term burning pain, and reflex sympathetic Neurological Features allodynia lies in the inference that dystrophy (RSD). The term causalgia In addition to the sensory loss result- might be drawn. If allodynia is simply was applied to cases in which nerve ing from the primary nerve injury, the a shift to the left of the response curve injury was the precipitating event. RSD patient suffers from pain and other of otherwise potentially nociceptive was applied to cases in which a nerve sensory disturbances. The pain is afferents, all that is required is a mecha- injury was not evident. usually burning in quality, intense, nism that lowers the threshold of acti- On clinical grounds, the vasomotor, continuous, with episodes of more vation of their pathways. This could sudomotor, temperature and trophic severe pain; and is usually felt distally readily be achieved by facilitating or changes, were inferred to indicate in the affected limb.7,8 disinhibiting their second-order neu- sympathetic overactivity or under- The other sensory disturbances are rones. However, if allodynia requires a activity, and it was the presence of hyperalgesia and allodynia. These change in modality, the mechanism these features that distinguished the terms were used to refer to the phe- cannot involve simply a lowering of syndromes from other painful condi- nomenon that the patients found that threshold, it must involve a switch, in tions due to nerve injury, musculoskel- touching, or even brushing the skin of which non-nociceptive afferents gain etal injury, or visceral disease. Classi- the affected part to be painful. These access to nociceptive pathways, be cal or archetypical descriptions of the features were regarded as due to that by developing totally new connec- two conditions were developed that sensitisation of intact nerve endings in tions, or opening latent or previously grouped the clinical features as injury, the affected limb by sympathetic activ- suppressed connections. neurological features and sympathetic ity, rendering them more easily acti- In the present article, when quoting features. vated by normal and subliminal stimuli. previous and especially older literature Evidence brought to bear in support of the term allodynia is used without fur- Causalgia this inference was that: ther qualification to mean whatever the Injury M sympathetic features were other- original author felt it to mean. Other- Partial nerve injury was regarded as wise prominent in the syndrome; wise, when considering the mecha- the cardinal aetiological factor in caus- M sensitivity could be abolished by nisms of this clinical feature, the terms algia. The most frequently affected interrupting sympathetic activity by brush allodynia and pressure hyper- nerves were said to be the sciatic, the sympathectomy or by sympathetic algesia, as defined above, are used. median, and the brachial plexus.7 nerve blocks,7-10 or by the infusion Causalgia was reported to occur in of guanethidine.11,12 9

10 Australasian Musculoskeletal Medicine November 2001 Mechanisms of Complex Regional Pain Syndromes M In patients successfully relieved of that is continuous and burning in qual- Sympathetic Features their pain and sensitivity, the injec- ity and usually felt distally in the af- The sympathetic features of RSD tion of noradrenaline intradermally fected limb. The pain is accompanied were grouped into three phases (Table immediately reproduced the caus- by hyperaesthesia and hyperalge- 1). 7 As in causalgia an initial angry algic symptoms.13 sia.7,17 The major difference between or inflammatory phase was typically RSD and causalgia is the lack in RSD, followed by a cold, dry, stiff and atrophic Sympathetic Features of obvious sensory loss. Otherwise the phase. The involvement of the sympa- The sympathetic features of causal- neurological features of the two condi- thetic nervous system in these changes gia were believed to evolve through an tions are remarkably similar. Indeed, was inferred because sympathetic early and a late phase.7 In the early there is no detectable difference in the blocks or guanethidine infusion could phase, the vascular changes consist description of pain given by patients reverse the changes, at least in the of vasodilation and consequent warmth with causalgia and those with RSD.18 early phases.7,9,10,11,20,21,22 The joint with sweating and redness. Later, the This lack of difference could be stiffness and muscle atrophy seen in vascular changes consist of vasocon- interpreted as suggesting that nerve the late phase could not be reversed by striction with consequent cooling and injury does occur in RSD, but that the neural blockade. cyanosis of the skin. The skin under- injury affects nerves that lack a cuta- Histological studies of the joints of goes atrophy and becomes glossy. neous distributions such as muscles patients with RSD, revealed various Hair loss occurs. Initially the subcuta- nerves and articular nerves, and there- degrees of synovial oedema, prolif- neous tissues are oedematous, but fore, escapes clinical detection. eration of synovial cells and capillar- later they stiffen. Similarly, joints swell As in causalgia, the neurological ies, fibrosis of the sub-synovium, and but later stiffen. In parallel, muscles features of RSD were believed to be some periarticular infiltration by chronic initially spasm but later atrophy. Bones due to facilitation of peripheral nerve inflammatory cells.23 Bone scans re- progressively become demineralised. endings by sympathetic efferents and vealed a predominant localisation of An attractive synopsis is that there is noradrenaline, for they could be re- nuclides in the juxta-articular region of an early angry phase with vasodila- lieved by sympathetic blockade7,9,10,19 bones suggesting a focal increase of tion, warmth, redness, swelling, and or intravenous guanethidine.11,20,21 blood flow to these areas.24 This in- spasm, followed by an atrophic phase TISSUE TEMPORAL PHASE of vasoconstriction, coldness, cyano- EARLY INTERMEDIATE LATE sis, induration, stiffness and osteoporo- sis. VASCULAR Warm Cold Cold Dry Sweating Reflex Sympathetic Dystrophy (RSD) SKIN Red Cyanotic Pale RSD shares many of the features of Glazed Smooth causalgia, and differs essentially only Glossy in the nature of the precipitating cause. HAIR Loss Denuded Injury The trauma is often trivial. RSD has NAILS Brittle Brittle been reported after simple sprains,7 Grooved Ridged dislocation,7 fracture,7,14 a crush in- jury,7 a surgical procedure,7,15 and SUBCUTANEOUS Edema Brawny Atrophy even simple venepuncture.16 Other Fat loss causes include spinal injury, cerebrov- ascular accidents, spinal cord injury, JOINTS Swollen Thick Fibrosis myocardial infarction, diabetic neu- Tender Stiff Ankylosis ropathy, and central nervous system disease such as multiple sclerosis (see MUSCLES Spasm Wasting Atrophy Appendix I). BONES Osteoporosis Atrophy Neurological Features Table 1. The sympathetic features of reflex sympathetic dystrophy grouped in temporal The cardinal feature of RSD is pain phases to describe the phases of the conditions. Based on Bonica.7 10

11 Australasian Musculoskeletal Medicine November 2001 Mechanisms of Complex Regional Pain Syndromes creased blood flow was inferred to be even myofascial pain syndromes.29 M intravenous clonidine interrupts the mechanism of demineralisation sympathetic transmission but has seen in RSD.24 Otherwise, critics30-35 have noted no effect on pain;33,44 Thermographic studies showed that that: M the effects of stellate ganglion blocks affected limbs may be warmer or colder M sympathetic features are not con- have never been controlled in any than the unaffected limb but more sistent, 33,36 skin temperature studies of causalgia;30,33,45 one commonly colder in chronic cases.25 changes are variable and may be study found that only 15 out 54 Temperature asymmetry, however, is the same, warmer, or cooler on the blocks satisfied criteria for an ef- not unique to RSD, for it can occur in affected side;37 therefore, this can- fective block;46 other pain states, by asymmetries not be a discriminating, diagnostic M stellate ganglion blocks are not tar- greater than 20C, and particularly when criterion;30 get specific; very little of the injectate greater than 30C are more frequent in M the cutaneous features of RSD do reaches the area of the stellate RSD than in other disorders.25 How- not necessarily imply abnormal ac- ganglion and much spreads else- ever, although skin temperature in RSD tivity of sympathetic nerves;33 they where;29 may not be significantly different from could be manifestations of normal M when compared to saline controls, that of the uninvolved limb, muscle responses to injury;30 coldness and intravenous guanethidine or reser- blood flow and resting blood flow are cyanosis could be due to hyper- pine has no diagnostic or therapeu- significantly increased.26 sensitivity to circulating amines33,35 tic efficacy;47-50 and warmth and redness could be M saline is just as effective as phen- Extension due to neuropeptides possibly re- tolamine in relieving pain;51-53 Perhaps the most bizarre feature of leased antidromically from sensory M investigations of the purported sym- RSD is its extension to regions well nerves;35 trophic changes can be pathetic and noradrenergic basis beyond the initially affected area. Scin- ascribed to disuse30 or immobilisa- of RSD have found decreased, tigraphic23,24,27 and neurologic studies tion;31 rather than increased, levels of have shown that subtle and substantial M abnormal skin temperatures can catecholamines in the venous blood changes can be detected in the oppo- occur in the absence of any of limbs affected by RSD;30,33,54,55 site limbs of patients with RSD and noradrenergic vasomotor innerva- M the intra-cutaneous injection of no- there has been one case report of RSD tion;35 radrenaline evokes pain in only a affecting the whole body after surgery M pain does not correlate with vaso- minority of patients but few patients for low back pain.28 motor or sudomotor activity, and remain sensitive to such injections causalgic pain can occur in the when re-examined 12-16 years Problems absence of vascular changes;32,33 later;56 Many problems befell the continued M microneurographic studies have de- M with respect to taxonomy, critics or wider recognition of causalgia and tected no abnormal sympathetic have asked how to classify patients RSD. Foremost was the definition of activity in patients with RSD;32,33,38- who lack sympathetic features or liminal cases. Although the classical 41 patients who have the sympathetic and archetypical descriptions rendered M the effect of sympathetic blocks is features but no pain.31 the recognition of florid cases straight- unpredictable, and does not pre- forward, they did not define early or dict the effect of sympathectomy;33 These observations strike at the heart minimal cases. Critics asserted that: M pain relief after blocks does not of the traditional, clinical models of M the label of RSD is quite practitioner correlate with the duration of effect causalgia and RSD and their diagno- dependent, ranging form a hyper- of sympathetic blocks,11,33,42 sis. Denied sympathetic blocks and algesic, sweaty, oedematous, cool M pain relief after blocks is independ- intravenous guanethidine, proponents appendage to simply any surgical ent of the thermal effects of are left with clinical features of ques- outcome that fails to meet the ex- blocks;11,33 tionable specificity upon which to make pectation of the operating sur- M sympathetic blocks relieve pain even the diagnosis. geon.29 when the causative lesion is proxi- M of patients labeled as having RSD, mal to the block;32 A Resolution perhaps 85% had nothing that even M pain is relieved by blocking the At a conference held in 1993, propo- approached RSD, and clearly had stellate ganglion with morphine nents of RSD29,57 agreed that: other diagnoses such as neuralgias, which does not produce block of M the term (RSD) had lost any clinical peripheral vascular disease, and sympathetic efferents;32,43 or research utility because of wide- 11

12 Australasian Musculoskeletal Medicine November 2001 Mechanisms of Complex Regional Pain Syndromes spread, indiscriminate use, with no otherwise account for the degree of diagnostic or descriptive criteria; pain and dysfunction. CRPS M the reflex that is required by the Type I Type II term has never been demonstrated; The condition previously knows as SMP SMP M the linkage to the sympathetic nerv- causalgia was reclassified as CRPS SID SID ous system is inconsistent and in- type II. Its diagnostic criteria were to constant ; be:1 Table 2. The four types of complex M the term dystrophy is used impre- 1. The presence of continuing pain, regional pain syndrome (CRPS). SMP; sympathetically maintained pain. SID; cisely and the features may not be allodynia or hyperalgesia after a sympathetically independent pain. present consistently. nerve injury, not necessarily limited to the distribution of the injured Indeed, a further dimension was They resolved to create a nomencla- nerve. added that did not prejudice the pri- ture that was based on a descriptive 2. Evidence at some time of oedema, mary diagnosis. It was recognised that method which was clinically useful but changes in skin blood flow, or ab- the pain of CRPS might be relieved by did not imply any particular mecha- normal sudomotor activity in the sympatholytic procedures or it might nism.29 They arrived at the term com- region of pain. not. Pain not so relieved was classified plex regional pain syndrome (CRPS) 3. The diagnosis is excluded by the as sympathetically independent pain on the grounds that existence of conditions that would (SID), whereas pain relieved by sym- Complex: recognised the intellec- otherwise account for the degree of pathetic blocks was classified as sym- tual and clinical complexity of the symp- pain and dysfunction. pathetically maintained pain (SMP). toms and signs encompassed by this Whether or not the pain could be rubric These revisions addressed several relieved by sympathetic blocks was not Regional: described the distribution criticisms that had been raised about considered an essential criterion for of the symptoms which is the hallmark RSD and causalgia. The emphasis on any condition. It was simply a feature of the conditions sympathetic features was reduced. that extended the classification to four Pain: is the sine qua non of the Instead, the emphasis lied on the pres- basic conditions (Table 2). condition. ence of pain and allodynia or hyperal- Syndrome: recognised that the con- gesia. Oedema, changes in skin blood Mechanisms dition was not ascribed to a single flow, or sudomotor activity needed to In the past, authorities ventured to aetiology, and represented a cluster of be present only at some time in the explain all the features of CRPS by symptoms and signs. course of the condition. A link to the singular, comprehensive models. sympathetic nervous system was not These models, however, were essen- This nomenclature was adopted for implied29 and, in particular, there was tially heuristic. They linked the various the second edition of the taxonomy of no implication that the sympathetic features descriptively into a single dis- the International Association for the nervous system was responsible in order, but afforded little or no insight Study of Pain.1 any way for the pain. into the specific mechanisms of each The condition previously known as RSD was reclassified as CRPS type I. Its diagnostic criteria were to be:1 1. The presence of an initiating nox- ious event, or a cause of immobili- sation; 2. Continuing pain, allodynia or hy- peralgesia with which the pain is disproportionate to any inciting event; 3. Evidence, at some time, of oedema or changes in skin flow, or abnor- mal sudomotor activity in the region of pain; 4. The diagnosis is excluded by the existence of conditions that would Figure 2. Livingstones model of causalgia. 12

13 Australasian Musculoskeletal Medicine November 2001 Mechanisms of Complex Regional Pain Syndromes feature. One of the earliest models, M electrical stimulation evokes pain tised to mechanical, thermal, and that of Livingstone,58 serves just as well from symptomatic tissues at stimu- chemical stimuli in patients with brush today as it did when it was first con- lus intensities that evoke only tactile allodynia, which implies ongoing activ- ceived (Fig. 2). Authors of later models sensations in normal skin;4,40,60,63- ity in these afferents.6,39 However, oth- acknowledge that theirs are essentially 65 ers have found no evidence of based on that of Livingstone.59 M brush-evoked allodynia is abolished sensitisation of C fibres or [email protected] The Livingstone model maintains that by nerve blocks at a time when Nevertheless, other studies have nerve injury creates a peripheral irri- tactile sensations are but other sen- shown that blocking afferent input from tative focus that, in turn, generates sations remain unaffected.5,38,40,62,66 sources of nociception, either by us- self-sustained loops in the spinal cord ing local anaesthetic blocks or by com- that generate muscle spasm, pain, and Brush allodynia also involves central pressing nerves, abolishes both spon- sympathetic activity. The latter causes neuronal plasticity. The evidence for taneous pain and allodynia.5,60,65,77 vasoconstriction and ischaemia in the this is indirect in humans but direct in It would, therefore, seem that ongo- periphery, forming metabolites that are laboratory animals. ing input from primary afferents is responsible both for the sympathetic In humans, the application of cap- essential for the maintenance of features of the condition and mainte- saicin to skin lowers the threshold for allodynia. The implication is that this nance of the irritative focus. activation of tactile mechanoreceptors input triggers central sensitisation. While encapsulating the essential in nearby skin unaffected by the cap- However, the mechanism by which features of CRPS such models do not saicin.5,60,66-69 nociceptive input initiates and main- offer insights into the mechanisms The mechanism of this sensitisation tains central sensitisation has not been involved. They do not explain the na- is central for it is evident upon electrical established. One conjecture is that ture of the irritative focus or how it stimulation of peripheral nerves, which nociceptive input facilitates second- generates self-sustained loops or bypasses any putatively sensitised order neurones through the action of what these actually are. Moreover, peripheral nerve endings.5,67 glutamate acting on NMDA receptors, these models accept that sympathetic Similar phenomena have been ob- and through the sustained action of activity is an essential part of the con- served in animals, and are associated substance P and neurokinin A.60 Neu- dition and mechanisms involved, which with expansion of the receptive fields of rokinin A has been shown to spread modern research has brought into WDR neurones and lamina I neurones beyond its immediate site of release question. Nevertheless, such models in the dorsal horn.70-75 following noxious stimulation,78 and have served to direct attention towards The expansion of receptive fields may well thereby excite distant neu- individual components of the syndrome explains the extension of allodynia to rones, rendering them more sensitive in the pursuit of the explicit mecha- regions beyond the immediate site of to peripheral input. An alternative con- nisms involved. injury in CRPS. jecture is that central sensitisation could Blocking peripheral nerves relieves be due to loss of inhibition of second- Brush Allodynia allodynia in regions beyond the terri- order neurones resulting from trans- Of all the features of CRPS, brush- tory of the affected nerve.65 synaptic degeneration of inhibitory evoked allodynia is the best under- Primary nociceptive input initiates inter-neurons caused by nociceptive stood. For allodynia there is a satisfy- and maintains brush allodynia. The excitotoxicity.4,60,74,79 ing model supported by experimental evidence for this is circumstantial. In essence, the mechanism of brush evidence both in humans and in labo- Some studies have shown that noci- allodynia can be summarised as shown ratory animals. ceptive primary afferents are sensi- in Figure 3. There is no evidence that Brush allodynia is mediated by A> fibres. The evidence for this is that: M the reaction time for this sensation is consistent with the conduction velocity of large myelinated afferents;4,60-63 M the pinprick threshold for brush- evoked allodynia is equal to, or nearly equal to, that of low threshold mechanoreceptors in healthy skin;4,60-63 Figure 3. The mechanisms of brush allodynia. 13

14 Australasian Musculoskeletal Medicine November 2001 Mechanisms of Complex Regional Pain Syndromes brush allodynia is sympathetically is rekindled by periodic nociceptive and the pursuit of a sympathetically mediated. Experiments have shown input in order to appear long-lasting. In mediated mechanism of pain applies that in patients in whom allodynia is animals, features of hyperalgesia re- to only a minority of patients. Neverthe- relieved by sympathetic blocks, elec- solve spontaneously;88 therefore, there less, the mechanisms that have been trical stimulation of A> fibres, and are no models, at present, of the long- proposed serve equally for SIP as they vigorous rubbing of the previously af- lasting hyperalgesia seen in humans.88 might for SMP. fected skin does not re-evoke Review articles have suggested four allodynia.80 This argues against pe- Spontaneous Pain possible mechanisms of the pain of ripheral sensitisation. Any role of the In the past, basic scientists who have CRPS. They are ephapses,90,92 sym- sympathetic nervous system must re- sought to explain the pain of CRPS pathetic afferents, 32,33,90,92 neuro- late only to the sensitisation of primary have explored not only the mecha- mas,92,93 and ectopic activity in dorsal nociceptive input or to the mainte- nisms of the pain but also its relation- root ganglia.88,92,94 Each of these re- nance of central sensitisation. How- ship to sympathetic activity. Their in- quires an injury to a peripheral nerve ever, any such role is dependent on the vestigations, however, predated the and, therefore, serves to explain the validity of the data concerning sympa- doubts that have been cast on the pain of CRPS type II. No explanations thetically maintained pain. validity of sympathetic blocks and, have been proffered for CRPS type I. therefore, the necessity of linking pain However, the pain (and other features) Static Hyperalgesia to sympathetic activity. of CRPS type I can be explained if it is The available evidence indicates that Accurate figures on the prevalence assumed that this condition involves static, or punctate, hyperalgesia is due of SMP are hard to find, but some occult (i.e., clinically unapparent) nerve to a shift to the left of the response studies suggest that only 45%89 or as injury. characteristics of nociceptive afferents, few as 36%52 or 33%77 of patients The ephapse model requires that, due to central sensitisation. with CRPS have SMP. Even fewer after nerve injury and at the site of Experimental injury to the skin pro- patients have genuine SMP if re- injury, connections develop between duces mechanical hyperalgesia in sponses to blocks are discounted for peripheral axons such that impulses normal volunteers5,60,66,8 that is medi- placebo effects.52 Phentolamine51-53 along one are transmitted to the other. ated by nociceptive afferents6,39,66,68 and guanethidine47,48-50 infusions are The connections could be between that exhibit increased sensitivity.82-84 just as effective as saline infusions and sensory afferents such that normal Central sensitisation must be operat- so cannot be regarded as specific stimuli along the distal segment of an ing because punctate hyperalgesia is tests of sympathetic mediation. The intact and non-nociceptive afferent are not abolished by peripheral blocks of only unchallenged hallmark of sympa- communicated to the proximal seg- the injured site68 and outlasts the spon- thetic mediation have been local an- ment of a nociceptive afferent, result- taneous pain induced by capsaicin aesthetic blocks of the sympathetic ing in non-noxious stimuli being per- injury to the skin.66 trunk. However, a recent study now ceived as painful. The connections In animal experiments, the extension calls even them into question. could be between efferent sympathetic of hyperalgesia to areas remote from In a cross-over study, Price et al90 fibres and nociceptive afferent fibres, the original site of injury is associated performed stellate ganglion blocks or such that efferent activity is reflected with expansion of the receptive fields of lumbar sympathetic blocks using ei- as nociceptive activity. second-order nociceptive neu- ther normal saline or local anaesthetic. Arguments against this model are rones.72,85-87 In terms of immediate pain relief and that: The inability of peripheral blocks to relief of allodynia and hyperalgesia, M such ephapses as do occur after relieve static hyperalgesia indicates the two agents were indistiguishable. nerve injury are not between the that the central sensitisation involved Local anaesthetic differed from nor- appropriate axons required by the differs from that which underlies brush mal saline only in that it afforded longer- model;90 allodynia. Whereas sensitisation to A> lasting relief. Consequently, the imme- M ephapses between sympathetic and input requires ongoing peripheral no- diate response to sympathetic blocks afferent fibres have not been iden- ciceptive activity, sensitisation to noci- cannot be held as a diagnostic crite- tified;45,59 ceptive input seems to be induced by rion for sympathetically mediated M if ephapses occur between distal a noxious stimulus but outlasts that pain.90 non-nociceptive axons and proxi- stimulus. What is not known is how long Consequently, the significance of mal nociceptive axons, the oppo- that sensitisation lasts: whether it is sympathetic mediation of pain may site should also occur such that self-limited or permanent; or whether it have been overestimated in the past, peripheral noxious stimuli would be 14

15 Australasian Musculoskeletal Medicine November 2001 Mechanisms of Complex Regional Pain Syndromes perceived as not painful (this has the passage of time a greater propor- elinated fibres become spontaneously not been observed);63 tion of axons discharge spontaneously active, both distal and proximal to the M ephapses take time to develop and, and become mechanosenstive.96-100 site of injury.103 The activity of C fibres therefore, cannot explain the early Moreover, the sprouts are sensitive to and [email protected] fibres is presumed to be the onset of pain;8.65,92 circulating adrenaline and noradrena- basis for pain induced by this type of M local anaesthetic delivered to the line, and the excitation of neuromas by lesion. The source this activity has not putative site of such ephapses does amines can be blocked by phen- been established for certain but one not relieve pain,92 and tolamine.91 This latter feature rendered interpretation is that it arises from M afferent activity from ephapses is neuromas particularly attractive as a growth cones from the axons at the site not synchronous with sympathetic source of SMP. of injury.103 The injured axons develop activity.90 The neuroma model is attractive in an increased number of sodium chan- that it provides a pathology consistent nels and an increased number of =- The model of sympathetic afferents with nerve injury and capable of pro- adrenergic receptors, which renders has been promoted by one author32,33 ducing spontaneous pain. However, them susceptible to spontaneous dis- largely on the grounds that other mod- while directly applicable to CRPS type charge and to stimulation by amines.9,91 els inadequately explain the pain of II, it is not applicable to CRPS type I, In effect, the injured axons behave like CRPS. Although the author refers to unless it is acknowledged that in CRPS neuromas, and the condition is some- earlier anatomical literature on the type I neuromas are formed on deep times regarded as a neuroma-in-con- existence of sympathetic afferents, nerves, and have hitherto been clini- tinuity.91 this work has not been corroborated by cally inaccessible. Moreover, the neu- The constriction model offers an modern studies; nor is there any con- roma model predicts that the pain of explanation of CRPS type without re- vincing physiological evidence of af- CRPS would be relieved by blocking quiring frank transection of a nerve, as ferent activity in sympathetic nerves in the neuroma, but peripheral blocks or in the case of neuroma. It can also be patients with CRPS. Earlier reports neurectomy do not always succeed in adapted to explain CRPS type I. So- that morphine injected around the relieving the pain of CRPS.8,32 The matic injuries might fail to injure a stellate ganglion relieves the pain of neuroma model has also been re- peripheral directly but focal swelling of CRPS without affecting vasomotor jected, at least for SMP, on the grounds injured tissues surrounding a periph- activity43 have been contradicted.94 that: eral might nonetheless constrict it. This model remains only a conjecture M there is no correlation between pain Ectopic impulse generation in dor- available for pursuit if other explana- and vasomotor activity;32 sal root ganglia88, 105,106 is an appeal- tions are less satisfying. M sympathetic activity is normal in ing alternative to the neuroma or con- Neuroma-formation is the one pro- CRPS;32,101 and striction models in that it explains why posed mechanism of pain in CRPS M substances other than adrenaline peripheral blocks, in some cases, fail that has most often been invoked in the and noradrenaline are equally ca- to relieve the pain of CRPS. Unfortu- literature on CRPS.35,45,90-93 However, pable of exciting neuromas, includ- nately, this model has barely been this does not necessarily argue that it ing these include acetylcholine, his- explored in experimental animals and is the most favoured or the best expla- tamine and prostaglandin E.32 not at all in clinical studies. The circum- nation. Rather, it may be only that stantial evidence is that: neuroma formation is the most studied An adaptation of the neuroma model M after transection of a peripheral and best understood pathophysiologi- is the constriction model.102 In ex- nerve, not only do neuromas de- cal phenomenon of nerve injury. There- perimental animals if ligatures are ap- velop but dorsal root ganglion cells fore, when authorities are called upon plied to a peripheral nerve so as to become spontaneously active;88,105- to offer explanation for CRPS they constrict it but not transect any of the 107 gravitate to what is most studied and axons, the animal develops pain, M dorsal root ganglion cells also be- best understood. allodynia and hyperalgesia.102 At the come active after constriction of a Neuromas occur when peripheral site of ligature, the axons are com- peripheral nerve;108 nerves are transected. Within hours of pressed by the ligatures and by the M the spontaneous activity that devel- transection, axon sprouts appear from oedema that occurs.103 Distally, axons ops after nerve constriction is not the cut end of the proximal segment. degenerate. Virtually all the myelinated abolished by transecting the af- Between two and 30 hours after injury, axons degenerate and nearly all the fected nerve proximal to the site of a small proportion of these axons ex- unmyelinated axons.103,104 Physiologi- injury or just distal to the dorsal root hibits spontaneous discharges.95 With cally, however, myelinated and unmy- ganglion, but it is totally abolished if 15

16 Australasian Musculoskeletal Medicine November 2001 Mechanisms of Complex Regional Pain Syndromes the dorsal root is transected proxi- but this is not always the case.64 both excitatory and inhibitory influ- mal to the dorsal root ganglion;108 M the model requires that the ences over multiple segments through M after nerve injury, dorsal root gan- sensitisation of WDR is maintained the dorsolateral tract. Normal sensa- glion cells receive a neo-innerva- not by nociceptive input but by input tion involves not simply the response of tion by sympathetic efferent fi- from large diameter afferents. It a single neurone at the level of entry of bres;109 predicts that sympathetic blocks a peripheral afferent, but a profile of M spontaneously active dorsal root would eliminate this sensitisation excitatory and inhibitory activity over ganglion cells are activated by by normalising the activity of large several segments. Transecting a pe- adrenaline, 88,106 and are sup- diameter afferents. Were that the ripheral nerve results in quite bizarre pressed by phentolamine.109 case, then stimulating large diam- sensory changes. These changes do eter afferents, electrically or by not involve ongoing peripheral activity, The latter phenomena render the vigorous rubbing of the skin, should but occur as a result of loss of periph- dorsal root ganglion model an attrac- reinstate the pain and allodynia eral input. They include development tive explanation of SMP. Moreover, the after a sympathetic block. This is of areas of numbness and areas of dorsal root ganglion model offers an not the case.4,64 Successful sym- hyperaesthesia but most strikingly, explanation of pain that is relieved by pathetic blocks eliminate hyperal- these areas are not fixed; they change stellate ganglion blocks but not by gesia, and protect the patient from size, and can be made to shrink or regional intravenous blocks of the up- re-activation of their pain.64,80 enlarge by manipulating the tonic in- per limb. hibitory functions of the dorsolateral The model that has attracted the Central Mechanisms tract either by injections of strychnine greatest acclaim is that of Roberts.110 Where all the foregoing models fail is or by selectively transecting the Indeed, it was hailed by Bonica as in the explanation of CRPS that devel- tract.114-116 brilliant.111 This model proposed that ops following lesions in the central These observations indicate that the at the time of injury, C fibres activate nervous system (Appendix I), in which wiring of the spinal cord is such that and sensitise wide dynamic range there is no peripheral injury, and no simple loss of input from the periphery (WDR) neurones in the spinal cord. basis for the formation of neuromas or can result in hyperaesthesia, not be- These neurones remain senstisied by the development of spontaneous activ- cause of sensitisation of the dorsal normal inputs from large diameter ity in the dorsal root ganglia. Indeed, horn, but through loss of inhibition. afferents whose activity is perceived the occurrence of CRPS after central Others have studied the same phe- as painful and is maintained by sympa- lesions has repeatedly been raised as nomenon more explicitly. thetic activity. In support of this model, a criticism of all peripheral-based Studies in cats have shown that, Roberts and colleagues showed in models of the pain of CRPS.32,33,92 For following peripheral deafferentation, animal experiments that only WDR this reason, several authors have gravi- receptive fields of dorsal horn neurons neurones were activated by sympa- tated towards a central mechanism increase117,118 but the extent of expan- thetic stimulation,112 and that such for the pain of CRPS, although without sion is too great to be accounted for by stimulation drove hair afferents and elaborating any particulars.8,92,93 Sun- axon sprouting.118 Rather, the investi- slowly adapting peripheral afferents.113 derland8 introduced the notion of a gators reasoned that the expansion Arguments raised against this model turbulence hypothesis, in which caus- was due to unmasking of latent are that: algia was caused by disordered activ- synapses, ostensibly through loss of M there is no correlation between pain ity in the spinal cord induced by retro- inhibition.117,118 Furthermore, earlier and vasomotor activity.32,33 grade and trans-synaptic degenera- work by Hillman and Wall119 had shown M the frequency of stimulation re- tion following peripheral nerve injury. that the peripheral receptive fields of quired to activate peripheral Nathan93 referred to the work of Denny- low threshold and high threshold receptors by sympathetic stimula- Brown114-116 as an explanation of the receptors overlap extensively, and have tion is large and in excess of what spread of pain and hypersensitivity. different excitatory and inhibitory ef- is normally encountered in sympa- The studies of Denny-Brown114-116 fects on dorsal horn neurons. More thetic nerves.59 revealed that the organisation of the significantly, they showed that these M sympathetic activity is normal in spinal cord and brainstem is far more receptive fields and their effects were CRPS.32,101 complex than the peripheral models of subject to descending modulation. M if WDR neurons were sensitised, CRPS currently admit. In the normal Blocking descending inhibition in- sensitivity should be also be evident state, segmental nerves ramify over creases the activity of dorsal horn cells for other modalities such as heat, multiple spinal cord segments and elicit and increases the sizes of their recep- 16

17 Australasian Musculoskeletal Medicine November 2001 Mechanisms of Complex Regional Pain Syndromes tive fields.119 of their condition, the mechanisms for the sympathetic features of Meanwhile, other studies have shown change. Thus, it might be that periph- CRPS.123,126 At rest, skin blood flow that deafferentation causes spontane- eral mechanisms operate early, but and skin temperature may be greater, ous activity in nociceptive neurons in more central mechanisms operate later, lower, or the same as on the unaffected the dorsal horn or trigeminal nucleus.120- when the condition becomes refrac- side,127 but if patients are acclimatised 122 This activity is not driven by periph- tory to peripheral interventions. to a warm environment, they exhibit eral input; indeed it can be exacer- essentially normal sympathetic reflexes. bated by spinal anaesthesia. Denied Sympathetic Features At most, the evidence suggests that in their accustomed peripheral input, The so-called sympathetic features the early phases of CRPS, vasocon- these neurones behave as if they have of CRPS almost defy explanation. The strictor drive is deficient.123,126 Moreo- unstable membranes and discharge confounding factors are the variation ver, the deficiency lies in the central spontaneously. Moreover, they lack between and within patients, and se- nervous system and not at spinal or receptors to conventional transmitter lection bias in studies of these patients. peripheral levels.126 substances, and are unreceptive to For example, Baron and Maier123 stud- Such deficiencies as do occur are iontophoretic application of GABA, ied only patients with cold limbs, selective for certain aspects of vaso- glycine, glutamate and homo- whereas Kurvers et al124 studied pa- motor control. Whereas vasoconstric- cysteine.120 tients with warm limbs. tor drive may be decreased, sudomo- Collectively these observations allow Traditional descriptions of the phases tor activity is normal or may be en- for a central model of the pain of or stages of CRPS (Table 1) are ide- hanced.128 Although thermoregulatory CRPS. The pain is not caused by alised and have not been corrobo- skin blood flow may be increased in peripheral nociceptive input but either rated. When tabulated according to early CRPS, nutritive skin blood flow is by peripheral deafferentation or by duration of symptoms, the sympa- not. Yet both are decreased in later loss of descending inhibition. Thus, thetic features of CRPS type I do not CRPS.124 These irregularities indicate the pain of CRPS could be a form of differ125. Early in the course of the that mechanisms other than, or in central pain, caused, in some cases, condition, a somewhat greater propor- addition to, sympathetic activity affect by peripheral deafferentation or, in tion of patients (86%) exhibit oedema, the vasomotor state of the affected other cases, by central lesions. Such but oedema is present in 55% of pa- limb, particularly in the later stages of a mechanism is the only one that can tients at 12 months. Osteoporosis on x- the condition. account for both peripheral and cen- ray is uncommon in patients with a Among the mechanisms suggested tral causes of CRPS. Allodynia and history shorter than two months, but is are: hyperalgesia occur in company with evident in some 40% of patients with a M hypersensitivity or upregulation of the pain not because of excitation or history longer than two months. The peripheral adrenoreceptors on facilitation, but as a result of loss of incidence of other features such as blood vessels;33,35,59 123,124,126 inhibition of surrounding segments. colour difference, temperature differ- M increased vascular permeability due ence, hyperhidrosis, trophic changes to inflammatory mediators;45,129 A Synthesis in hair or nails, as well as well and M antidromic activity in C-fibres caus- Just as peripheral models do not neurological features, does not differ ing vasodilatation.35,130 explain the pain suffered by patients with time125. with central causes of CRPS, the cen- When tabulated according to whether Accordingly, the sympathetic fea- tral model does not explain those cases the affected limb is warm or cold, the tures of CRPS may involve a mixture of in which peripheral somatic blocks still sympathetic features do not differ. various mechanisms at different times relieve their pain. A diplomatic synthe- Oedema occurs somewhat more fre- or at different stages of the condition. sis could be that there is no singular quently in patients with warm limbs and Decreased vasoconstriction might explanation for the pain of CRPS. a short history; and trophic changes complement antidromic or inflamma- Rather, it might be that different pa- are more common in patients with a tory vasodilatation, but when vasocon- tients suffer injuries at different sites cold limb and a longer history. How- strictor drive returns it might compete along a common pathway. As a result, ever, the incidence of hyperhidrosis, with antidromic or inflammatory va- patients may resemble one another abnormal nail growth or hair growth, sodilatation, resulting in unstable and clinically, but the mechanisms of their motor features or sensory features variable features. pain are slightly different. Another does not differ.124 Regardless of the mechanism of va- modification is that perhaps as pa- Modern evidence clearly discounts somotor disturbances contemporary tients evolve through different phases sympathetic overactivity as the basis authorities agree that there is no corre- 17

18 Australasian Musculoskeletal Medicine November 2001 Mechanisms of Complex Regional Pain Syndromes lation between sympathetic dysfunction Summary Nerve injury might cause deafferen- and pain.32,33,123,126 Given the available evidence, tation and/or neuroma formation, or With respect to central causes of Livingstones model can be elaborated involve a constriction injury of the nerve. CRPS (Appendix I), peripheral mecha- as shown in Figure 4. The model allows Neuroma formation or constriction in- nisms of the sympathetic features can- for either a peripheral nerve injury to jury causes spontaneous activity in C not be invoked. The only explanation initiate the process, or a central lesion fibres and [email protected] fibres, either at the site must be disturbed descending control of the nervous system. The model of injury or in dorsal root ganglion cells. of sympathetic drive. presumes that in CRPS type I an occult This activity is transmitted to the nerv- nerve injury occurs. ous system where it excites and facili- Figure 4. A model of the mechanisms of CRPS. 18

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Pain Neurol 1981; 72: 63-81. ent neuronal plasticity following tissue in- 1984; 19: 235-47. 100. Devor M, Janig W. Activation of myeli- jury and inflammation. Trends in Neurosci 86. Cook AJ, Woolf CJ, Wall PD, McMahon nated afferents ending in a neuroma by 1992; 15: 96-103. SB. Dynamic receptive field plasticity in rat stimulation of the sympathetics. Neurosci 75. Woolf CJ, Shortland P, Sivilotte LG. spinal cord dorsal horn following C-primary Lett 1981; 24: 43-47. Sensitization of high mechanothreshold afferent input. Nature1987; 325: 151-53. 101. Torebjork HE, Hallin RG. Micro- superficial dorsal horn and flexor motor 87. Hylden JL, Nahin RL, Traub RJ, Dubner neurographic studies of peripheral pain neurones following chemosensitive primary R. Expansion of receptive fields of spinal mechanisms in man. In: Bonica JJ, afferent activation. Pain 1994; 58: 141-55. lamina I projection neurons in rats with Liebeskind JC, Albe-Fessard DG (eds). 76. La Motte RH, Lundberg LER, Torebjork unilateral adjuvant-induced inflammation: Advances in Pain Research and Therapy, HE. Pain, hyperalgesia and activity in noci- the contribution of dorsal horn mechanisms. Volume 3. New York, Raven Press, pp 121- ceptive C units after intradermal injection of Pain 1989; 37: 229-43. 131. capsaicin. J Physiol 1992; 448: 749-64. 88. Wall PD. Noradrenaline-evoked pain in 102. Bennett GJ, Xie YK. A peripheral 77. Arner S, Lindblom U, Meyerson BA, neuralgia. Pain 1995; 63: 1-12. mononeuropathy in the rat that produces Molander C. Prolonged relief of neuralgia 89. Raja SN, Treede RD, Davis KD, disorders of pain sensation like those seen after regional anesthetic blocks. A call for Campbell JN. Systemic alpha-adrenergic in man. Pain 1988; 33:87-1077. further experimental and systematic clini- blockade with phentolamine: a diagnostic 103. Kajander KC, Bennett GJ. Onset of a cal studies. Pain 1990; 43: 287-97. test for sympathetically maintained pain. painful peripheral neuropathy in rat: a par- 78. Duggan AW, Hope PJ, Jarrott B, et al. Anesthesiol 1991; 74: 691-98. tial and differential deafferentation and spon- Release, spread and persistence of immu- 90. Price DD, Long S, Wilsey B, Rafii A. taneous discharge in Ab and Ad primary noreactive neurokinin A in the dorsal horn Analysis of peak magnitude and duration of afferent neurons. J Neurophysiol 1992; 68: of the cat following noxious cutaneous analgesia produced by local anesthetics 734-44. stimulation. Studies with antibody injected into sympathetic ganglia of com- 104. Basbaum AI, Gautron M, Jazat F, et al. microprobes. Neurosci 1990; 35: 195-202. plex regional pain syndrome patients. Clin The spectrum of fiber loss in a model of 79. Sugimoto T, Bennett GJ, Kajander KC. J Pain 1998; 14: 216-26. neuropathic pain in the rat: an electron 21

22 Australasian Musculoskeletal Medicine November 2001 Mechanisms of Complex Regional Pain Syndromes microscopic study. Pain 1991; 47: 359-67. fields of lamina 5 spinal cord neurons. 1979, pp 141-66. 105. Devor M. Neuropathic pain and injured 120. Macon JB. Deafferentation hyperac- 3. Davis SW, Petrillo CR, Eichberg RD, nerve: peripheral mechanisms. Brit Med tivity in the monkey spinal trigeminal nu- Chu DS. Shoulder hand syndrome in a Bull 1991; 47: 619-30. cleus: neuronal responses to amino acid hemiplegic population: a 5-year retrospec- 106. Wall PD, Devor M. Sensory afferent iontophoresis. Brain Res 1979; 161: 549- tive study. Arch Phys Med Rehabil 1977; impulses from dorsal root ganglia. Pain 54. 58: 353-56. 1983; 17: 321-39. 121. Loeser JD, Ward AA. Some effects of 4. Gellman H, Echert RR, Botte MJ, et al. 107. Burchiel KJ. Spontaneous impulse deafferentation on neurons of the cat spinal Reflex sympathetic dystrophy in cervical generation in normal and denervated dor- cord. Arch Neurol 1967; 17: 620-36. spinal cord injury patients. Clin Orthop 1988; sal root ganglia: sensitivity of alpha-adren- 122. Loeser JD, Ward AA, White LE. 233: 126-31. ergic stimulation and anoxia. Exp Neurol Chronic deafferentation of human spinal 5. Gellman H, Keenan, MA, Stone L, et al. 1984; 85: 257-72. cord neurons. J Neurosurg 1968; 29: 48- Reflex sympathetic dystrophy in brain in- 108. Kajander KC, Wakisaka S, Bennett 50. jured patients. Pain 1995; 51: 307-11. GJ. Spontaneous discharge originates in 123. Baron R, Maier C. Reflex sympathetic 6. Greyson ND, Tepperman PS. Three- the dorsal root ganglion at the onset of a dystrophy: skin blood flow, sympathetic phase bone studies in hemiplegia with re- painful peripheral neuropathy in the rat. vasoconstrictor reflexes and pain before flex sympathetic dystrophy and the effect Neurosci Lett 1992; 138: 225-28. and after surgical sympathectomy. Pain of disuse. J Nucl Med 1984; 25: 423-29. 109. McLachlan EM, Janig W, Devor M, 1996; 67: 317-26. 7. Hathaway BN, Hill GE, Ohmura A. Cen- Michaelis M. Peripheral nerve injury trig- 124. Kurvers HAJM, Jacobs MJHM, Beuk trally induced sympathetic dystrophy of the gers noradrenergic sprouting within dorsal RJ, et al. Reflex sympathetic dystrophy: upper extremity. Anesth Analg 1978; 57: root ganglia. Nature 1993; 363: 543-46. evolution of microcirculatory disturbances 373-74. 110. Roberts WJ. A hypothesis on the in time. Pain 1995; 60: 333-40. 8. Loh L, Nathan PW, Schott GD. Pain due physiological basis for causalgia and re- 125. Veldman PH, Reynen HM, Arntz IE, to lesions of the central nervous system lated pain. Pain 1986; 24: 297-311. Goris RJ. Signs and symptoms of reflex removed by sympathetic block. Br Med J 111. Bonica JJ. Causalgia and other reflex sympathetic dystrophy: prospective study 1981; 282: 1026-28. sympathetic dystrophies. In: Bonica JJ (ed). of 829 patients. Lancet 1993; 342: 1012- 9. Ohry A, Brooks ME, Steinbach TV, Rozin The Management of Pain. 2nd end. Phila- 16. R. Shoulder complications as a cause of delphia; Lea and Febiger, 1990, pp 220-43. 126. Birklein F, Riedl B, Neundorfer B, delay in rehabilitation of spinal cord injured 112. Roberts WJ, Foglesong ME. I. Spinal Handwerker HO. Sympathetic vasocon- patients. (Case reports and review of the recordings suggest that wide-dynamic- strictor reflex pattern in patients with com- literature.) Paraplegia 1978; 16: 310-16. range neurons mediate sympathetically plex regional pain syndrome. Pain 1998; 10. Subbarao J, Stillwell GK. Reflex sym- maintained pain. Pain 1988; 34: 289-304. 75: 93-100. pathetic dystrophy syndrome of the upper 113. Roberts WJ, Foglesong ME. II. Identi- 127. Tahmoush AJ, Malley J, Jennings JR. extremity: analysis of total outcome of fication of afferents contributing to sympa- Skin conductance, temperature, and blood management of 125 cases. Arch Phys thetically evoked activity in wide-dynamic- flow in causalgia. Neurol 1983; 33: 1483- Med Rehab 1981; 62: 549-54. range neurons. Pain 1988; 34: 305-14. 86. 11. Swan DM, McGowan JM. Shoulder- 114. Kirk EJ, Denny-Brown D. Functional 128. Birklein F, Sittl R, Spitzer A, et al. hand syndrome following myocardial inf- variation in dermatomes in the macaque Sudomotor function in sympathetic reflex arction. JAMA 1951; 146: 774-77. monkey following dorsal root lesions. J dystrophy. Pain 1997; 69: 49-54. 12. Schapira D, Barron SA, Nahir M, Scharf Comp Neurol 1970; 139: 307-309. 129. Oyen WJ, Arntz I, Claessens RM, at Y. Reflex sympathetic dystrophy syndrome 115. Denny-Brown D, Kirk EJ, Yanagisawa al. Reflex sympathetic dystrophy of the coincident with acute diabetic neuropathy. N. The tract of Lissauer in relation to sen- hand: an excessive inflammatory response. J Rheumatol 1988; 15: 120-22. sory transmission in the dorsal horn of Pain 1993; 55: 151-57. 13. Tepperman PS, Greyson ND, Hilbert L spinal cord in the macaque. J Comp Neurol 130. Ochoa JL, Yarnitsky D, Marchettini P, et al. Reflex sympathetic dystrophy in hemi- 1973; 151: 175-200. et al. Interactions between sympathetic plegia. Arch Phys Med Rehabil 1984; 65: 116. Denny-Brown D, Yanagisawa N. The vasoconstrictor outflow and C nociceptor- 442-47. function of the descending root of the fifth induced antidromic vasodilatation. Pain 14. Wainapel SF, Freed MM. Reflex sym- nerve. Brain 1973; 96: 783-841. 1993; 54: 191-96. pathetic dystrophy in quadriplegia: case 117. Devor M, Wall PD. Effect of peripheral report. Arch Phys Med Rehabil 1984; 65: nerve injury on receptive fields of cells in Appendix I. Literature on Visceral and 35-36. the cat spinal cord. J Comp Neurol 1981; Neurological Causes of RSD 199: 277-91. 1. Andrews LG, Armitage KJ. Sudecks 118. Pubols LM, Goldberger ME. Recovery atrophy in traumatic quadriplegia. Paraple- of function in dorsal horn following partial gia 1971; 9:159-165. deafferentation. J Neurophysiol 1980; 2. Bonica JJ. Causalgia and other reflex 43:102-117. sympathetic dystrophies. In: Bonica JJ et 119. Hillman P, Wall PD. Inhibitory and al. (eds). Advances in Pain Research and excitatory factors influencing the receptive Therapy. Vol 3. New York; Raven Press, 22

23 Australasian Musculoskeletal Medicine November 2001 Australasian Faculty of Musculoskeletal Medicine Practice Standards and Protocols: Lumbar Medial Branch Blocks The following guidelines have been officially endorsed by the Australasian Faculty of Musculoskeletal Medicine. These are the first published guidelines on medial branch blocks and radiofrequency ablation for the lumbar and cervical spine. They represent the standard that the AFMM expects of its members or professionals to whom they refer for these services. Definition technique succeeded in severing the In 1994 Schwarzer et al13 estab- L umbar medial branch blocks nerves to the lumbar zygapophysial lished that in younger aged, injured are a diagnostic procedure joints;7-10 but the concept of zyga- workers with chronic low back pain, designed to test whether a pophysial joint pain remained an at- the prevalence of lumbar zygapophysial patients pain is mediated by one or tractive explanation for some cases of joint pain was about 15%. The next more of the medial branches of the low back pain. Anatomical studies year, Schwarzer and others14 estab- lumbar dorsal rami. They involve showed that the articular branches to lished that its prevalence in older, non- anaesthetising the target nerve with a the lumbar zygapophysial joints could injured, rheumatology patients was tiny volume of local anaesthetic in an not be accurately targeted for percu- 40%. These studies showed that effort to relieve the patients pain. taneous procedures but their parent zygapophysial joint pain was common. By convention, lumbar medial branch nerves, the medial branches of the Questions remained, however, con- blocks are used to test whether a lumbar dorsal rami, did constitute a cerning the validity of medial branch patients pain stems from a given lum- valid and accessible target.9-12 It also blocks for the diagnosis of this pain. bar zygapophysial joint. For that pur- appeared logical that, if neurotomy These were answered by Dreyfuss pose, the nerves that innervate the joint was the basis of treatment for and colleagues in 1997 and 1998. are anaesthetised. zygapophysial joint pain, local anaes- Dreyfuss et al15 showed that lumbar This convention is based on the thetic blocks of the medial branches medial branch blocks were target spe- argument that, of all the structures would be the basis of diagnosing this cific, provided that precise target points innervated by the medial branches of pain and predicting response to neu- were accurately used, and that nee- the lumbar dorsal rami, the rotomy. For this purpose, target points dles were introduced in a particular zygapophysial joints are the only ones for anaesthetising the lumbar medial direction. Structures other than the that might harbour a discrete, focal branches under fluoroscopy were target nerves were not anaesthetised source of chronic pain.1 No pathology defined, and diagnostic blocks of these by lumbar medial branch blocks. Kaplan capable of producing chronic pain is nerves were advocated as the appro- et al16 showed that normal volunteers known to affect the segmentally spe- priate diagnostic test for zygapophysial were protected from experimentally cific muscles innervated by the dorsal joint paint hat was to be treated by induced lumbar zygapophysial joint rami. For this reason, and because the medial branch neurotomy.7 pain if the appropriate medial branches ensuing term is shorter and more ob- The subsequent history of lumbar were anaesthetised. Together, these vious in meaning, lumbar medial branch medial branch blocks became studies showed that lumbar medial blocks can be, and have been referred swamped by and confused with the branch blocks were target specific and to as (one of the means of achieving) use of intra-articular injections for the were a valid test of zygapophysial joint zygapophysial joint blocks. diagnosis of lumbar zygapophysial joint pain. pain. Indeed, papers describing intra- Subsequently, van Kleef et al17 dem- Historical Background articular injections dominated the lit- onstrated that lumbar medial branch The development of lumbar medial erature on zygapophysial joint pain neurotomy was not a placebo, and branch blocks was prompted by claims during the 1980s. However, once it Dreyfuss et al18 showed that dramatic in 1971 that back pain could arise from emerged that intra-articular injections and lasting relief from back pain could the lumbar zygapophysial joints, and of steroids did not provide lasting relief be achieved with lumbar medial branch that this pin could be treated by sever- from lumbar zygapophysial joint pain, neurotomy in patients carefully diag- ing the nerves that innervated these lumbar medial branch neurotomy re- nosed with controlled diagnostic blocks joints. Rees claimed that the nerves mained the singular means of possibly of their lumbar medial branches. Ac- could be severed percutaneously with a providing relief from this pain. Conse- cordingly, lumbar medial branch blocks special scalpel,1,2 and later Shealy3-6 quently, the utility of lumbar medial were shown to have both diagnostic claimed that they could be coagulated branch blocks became bound with the utility and therapeutic utility. with a radiofrequency electrode. issues of the prevalence of zyga- Given this background, lumbar me- It was subsequently shown that nei- pophysial joint pain and the efficacy of dial branch blocks have replaced, or ther the Rees technique nor the Shealy lumbar medial branch neurotomy. should replace, intra-articular inject- 23

24 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks tions in the diagnosis of lumbar 10. Bogduk N, Long DM. Percutane- If pain is not relieved, the target zygapophysial joint pain. ous lumbar medial branch neurotomy. nerves cannot be regarded as mediat- M Medial branch blocks are relatively A modification of facet denervation. ing the patients pain. A new hypoth- easier to perform Spine 1980; 5: 193-200. esis about the source of pain is re- M Medial branch blocks are safer and 11. Bogduk N, Wilson AS, Tynan W. quired. The pain may perhaps be more expedient 1982 The human lumbar dorsal rami. J mediated by other medial branches, or M Medial branch blocks are more Anat 1982; 134: 383-97. it may arise from a source not inner- easily subjected to controls 12. Bogduk N: The innervation of the vated by the lumbar medial branches. M Intra-articular blocks, if positive, lumbar spine. Spine 1983; 8: 286-93. If pain is relieved, the response lack a valid subsequent treatment 13. Schwarzer AC, Aprill CN, Derby R, constitutes prima facie evidence that M Intra-articular blocks lack proven et al. Clinical features of patients with the targeted nerves are mediating the therapeutic utility and predictive pain stemming from the lumbar patients pain; but steps need to be validity zygapophysial joints. Is the lumbar taken to ensure that the observed re- M Medial branch blocks, if positive, facet syndrome a clinical entity? Spine sponse is not false positive. can be followed by radiofrequency 1994; 19: 1132-37. It is possible that a patient may have neurotomy 14. Schwarzer AC, Wang S, Bogduk several sources of pain. For example: M Medial branch blocks have thera- N, et al. Prevalence and clinical fea- M they may have pain bilaterally at a peutic utility and predictive validity. tures of lumbar zygapophysial joint given segmental level, in which case pain: a study in an Australian popula- anaesthetising the left nerves should References tion with chronic low back pain. Ann relieve the left side of their pain but 1. Rees WES. Multiple bilateral subcu- Rheum Dis 1995; 54: 100-106. not the right side (and vice versa); taneous rhizolysis of segmental nerves 15. Dreyfuss P, Schwarzer AC, Lau P, M they may have pain from more than in the treatment of the intervertebral et al. Specificity of lumbar medial branch one segmental level on the one disc syndrome. Ann Gen Pract 1971; and L5 dorsal ramus blocks: a com- side, in which case anaesthetising 16:126-27. puted tomographic study. Spine 1997; the upper one or two of a series of 2. Rees WES. Multiple bilateral percu- 22: 895-902. nerves may relieve only the upper taneous rhizolysis. Med J Aust 1975; 16. Kaplan M, Dreyfuss P, Halbrook B, half of their pain. 1:536-37. et al. The ability of lumbar medial 3. Shealy CN. Facets in back and branch blocks to anesthetize the In either instance, complete relief of sciatic pain. Minn Med 1974; 57:199- zygapophysial joint. Spine 1998; 23: all pain cannot be expected. Indeed, 203. 1847-52. complete relief of all pain is contrary to 4. Shealy CN. The role of the spinal 17. van Kleef M, Barendse GAM, what should be expected. Rather, a facets in back and sciatic pain. Head- Kessels A, et al. Randomized trial of positive response can be entertained if ache 1974; 14:101-104. radiofrequency lumbar facet there is complete relief of pain in a 5. Shealy CN. Percutaneous denervation for chronic low back pain. distinct topographical region that con- radiofrequency denervation of spinal Spine 1999; 24: 1937-42. stitutes part of the patients total com- facets. J Neurosurg 1975; 43: 448-51. 18. Dreyfuss P, Halbrook B, Pauza K, plaint, but which corresponds to the 6. Shealy CN. Facet denervation in the et al. Efficacy and validity of area from which pain could be ex- management of back sciatic pain. Clin radiofrequency neurotomy for chronic pected to be mediated by the nerves Orthop 1976; 115: 157-64. lumbar zygapophysial joint pain. Spine anaesthetised. Although this may con- 7. Bogduk N, Colman RRS, Winer 2000, 25: 1270-77. stitute only partial relief of all of the CER. An anatomical assessment of patients pain, it is more accurately the percutaneous rhizolysis proce- and more informatively viewed as com- dure. Med J Aust 1977; 1: 397-99. Principles plete relief of pain in the region 8. King JS, Lagger R. Sciatica viewed The explicit purpose of lumbar me- targeted. Remaining areas of pain as a referred pain syndrome. Surg dial branch blocks is to test whether the may be targeted separately, or blocks Neurol 1976; 5: 46-50. patients pain is relieved by anaesthe- might be extended (within reason) to 9. Bogduk N, Long DM. The anatomy tising the nerves targeted. They are not include additional nerves that subtend of the so-called articular nerves and a test of the patients veracity. They test those remaining areas. their relationship to facet denervation the hypothesis raised by the treating Lumbar medial branch blocks have in the treatment of low back pain. J doctor that perhaps the pain is medi- diagnostic utility. If positive, they iden- Neurosurg 1979; 51: 172-77. ated by the nerves specified. tify the source of pain. Establishing a 24

25 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks positive diagnosis protects the patient rated into routine and conventional What constitutes innocuous, seri- from the futile pursuit of other and practice. ous and dire is a matter of consid- competing diagnoses, and from un- A true positive response to compara- eration and decision between the phy- dergoing presumptive treatment or tive local anaesthetic blocks is one in sician, the patient, and any other par- treatment that is not appropriate for which the patient reports complete ties involved such as an ethics commit- pain mediated by the lumbar medial relief of pain for a shorter duration tee or institutional review board. branches. when a short-acting agent is used, and Notwithstanding these intellectual and Lumbar medial branch blocks have for a longer duration when a long- clinical considerations, controlled di- therapeutic utility. A positive response acting agent is used. Such a response agnostic blocks are also cost-effec- predicts a good chance of obtaining is referred to as concordant in that it tive.2 Failing to confirm a diagnosis complete relief of pain from percuta- is concordant with the expected action with controlled blocks results in pa- neous radiofrequency neurotomy. of the agents used.1 tients with false positive responses to If a patient obtains complete relief of uncontrolled blocks undergoing treat- Control Blocks pain but does not report an appropriate ment. This not only results in a high rate Control blocks are essential to ex- differential response in terms of dura- of treatment failures, but also waste clude false positive responses, and to tion of relief, the joint is not excluded as resources by having practitioners ex- maximise the confidence of a securing the source of pain. Such paradoxical pend their time and skills treating pa- a true positive response. The most responses may still be consistent with tients who will not benefit. Controlled rigorous form of control is the use of a the hypothesis being tested. blocks reduce this wastage.2 placebo injection of normal saline un- What should be the criteria for a der double blind conditions, but logistic positive response to comparative local References and ethical considerations militate anaesthetic blocks is a matter of judge- 1. Barnsley L, Lord S, Bogduk N. against the use of normal saline in ment for the physician. However, the Comparative local anaesthetic blocks conventional practice. following principles apply. in the diagnosis of cervical The injection of saline ethically would If the consequences of a false posi- zygapophysial joints pain. Pain 1993; require informed consent. Impromptu, tive diagnosis are relatively innocu- 55: 99-106. single blind injections of normal saline ous, less stringent criteria can be used. 2. Bogduk N, Holmes S. Controlled are unethical. Complete relief of pain on each of two zygapophysial joint blocks: the trav- If saline is used it would have to be in occasions, regardless of the duration esty of cost-effectiveness. Pain Med the context of three blocks of the same of relief, will ensure that all patients with 2000; 1: 25-34. joint. The first block would have to be zygapophysial joint pain will be de- with an active agent in order to estab- tected, i.e., ruled in, but the cohort so lish, prima facie, that the joint is symp- identified will include false positive Indications tomatic. (There is no point in perform- cases. This may not matter if irrevers- The fundamental indication for lum- ing routinely a series of three, control- ible therapies are not being consid- bar medial branch blocks is the desire led blocks in a patient in whom there is ered. But physicians should be aware to know whether the patients pain is no objective indication that medial that the inclusion of false positive cases mediated by the medial branches of branches are at all mediating the pa- will undermine the success rate of any the lumbar dorsal rami. This principle tients pain.) The second block could treatment. emphasises the fact that back pain, not be the normal saline control, for a If the consequences of a false posi- per se, is not an indication for diagnos- mischievous patient would know that tive diagnosis are serious, more strin- tic blocks. Not all patients need diag- the second injection is always the gent criteria should be used. In such nostic blocks, so not all patients should dummy and could respond appropri- circumstances, the response must be undergo blocks. ately. In order to maintain the control- reliably true positive. The criteria for a Legitimate reservations can be raised ling effect of chance and blinding, the concordant response are appropriate about the need to perform blocks if the second block would have to be either for this purpose. patient is going to be treated conserva- normal saline or an active agent, and If the consequences of a false posi- tively. In that event, the response to the third block would need to be the tive diagnosis are dire, it would be blocks does not affect management, reciprocal agent. imperative to perform triple blocks with and performing blocks can be viewed Comparative local anaesthetic blocks saline controls, in order to be certain as superfluous. The only proposition constitute a more practical form of that the response is beyond doubt a that might be entertained is that medial control, that can be readily incorpo- true positive response. branch blocks have diagnostic utility 25

26 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks and, therefore, establishing a causes of back pain, such as infec- References positivediagnosis might curtail the fut- tion, tumours, vascular disease, and 1. Schwarzer AC, Aprill CN, Derby R, ile pursuit of other diagnoses. That metabolic disease, have been excluded et al. The prevalence and clinical fea- proposition, however, needs to be by careful and thorough history and tures of internal disc disruption in pa- weighed carefully against the likeli- examination, laboratory tests, and tients with chronic low back pain. Spine hood of obtaining negative responses. medical imaging. The work-up should 1995; 20: 1878-83. Proving that patients do not have a provide a diagnosis of lumbar spinal 2. Schwarzer AC, Wang S, Bogduk N, condition that they are unlikely to have pain of unknown origin, uncomplicated et al. Prevalence and clinical features is a waste of the skills and resources of by associated features other than per- of lumbar zygapophysial joint pain: a the investigator. Those skills could be haps restricted motion. study in an Australian population with better channelled into procedures and There are no clinical features that chronic low back pain. Ann Rheum actions that have a greater chance of allow a physician to predict with con- Dis 1995; 54: 100-106. improving patient outcome. For this fidence that a patient with back pain will 3. Schwarzer AC, Derby R, Aprill CN, reason, attention should be paid to respond positively to lumbar medial et al. Pain from the lumbar zygapoph- careful patient selection (see below). branch blocks. Multiple studies have ysial joints: a test of two models. J The only validated treatment for pain shown a lack of correlation between Spinal Disord 1994; 7: 331-36. mediated by the lumbar medial the results of conventional clinical ex- 4. Revel M, Poiraudeau S, Auleley GR, branches is percutaneous radio- amination and the response to control- et al. Capacity of the clinical picture to frequency neurotomy. If this treatment led blocks.1-4 Nor are features seen on characterize low back pain relieved by is not available, the conduct of medial CT scan predictive of response to facet joint anesthesia. Proposed crite- branch blocks can be justified only on blocks.5 ria to identify patients with painful facet the grounds of their diagnostic utility. There are, however, certain features joints. Spine 1998; 23: 1972-77. However, if radiofrequency neurotomy described by Revel4 that increase the 5. Schwarzer AC, Wang S, ODriscoll is available, medial branch blocks are likelihood of zygapophysial joint pain. D, et al. The ability of computed tom- essential prerequisite before enter- They are age greater than 65, pain ography to identify a painful taining radiofrequency neurotomy. relieved by recumbency, and absence zygapophysial joint in patients with Medial branch blocks are not indi- of aggravation of pain by coughing, by chronic low back pain. Spine 1995; 20: cated for acute back pain. There is a forward flexion, by rising from flexion, 907-12. high chance of acute back pain recov- by hyperextension, or by extension- 6. Bogduk N. Commentary on the ering, regardless or even despite con- rotation.4 If five or more of these fea- capacity of the clinical picture to char- servative treatment, and radio- tures are evident, the likelihood ratio acterize low back pain relieved by frequency neurotomy is not indicated for a positive response to blocks is facet joint anesthesia. Pain Med J for acute pain. Therefore, it is not nec- three.6 Consequently, the presence of Club J 1998; 4: 221-22. essary to perform diagnostic blocks in these features triples the likelihood of 7. McCall IW, Park WM, OBrien JP. patients with acute back pain. In princi- zygapophysial joint blocks being posi- Induced pain referral from posterior ple, therefore, medial branch blocks are tive.6 Even so, given the low prevalence elements in normal subjects. Spine indicated only for patients with chronic of lumbar zygapophysial joint pain, the 1979; 4: 441-46. pain. However, it could be conceded likelihood of a positive response is 8. Mooney V, Robertson J. The facet that there is merit in investigating pa- barely one in three.7 If the clinical syndrome. Clin Orthop 1976; 115: tients with subacute pain, whose pain is features are not evident, one needs 149-56. not improving or responding to con- carefully to consider the propriety of servative management. Although it has pursuing diagnostic blocks. Their yield not been demonstrated, the proposition is likely to be low, and the patient should Contraindications is attractive that pinpointing the source be forewarned of that, rather than Absolute of pain in these patients and promptly being lulled into optimism by the enthu- The absolute indications for lumbar treating it could avert the onset of chronic siasm of the investigator. medial branch blocks are conditions in pain behaviour. Somatic referred pain into the lower which the conduct of a needle proce- limb is not a contra-indication for lum- dure under x-ray control might jeop- Patient Selection bar medial branch blocks. Pain re- ardize the patients health. These in- A fundamental criterion for the se- ferred as far as the leg and foot has clude, but are not necessarily limited to lection of patients for lumbar medial been relieved by anaesthetising lum- the following: branch blocks is that serious possible bar zygapophysial joints.7,8 bacterial infection, systemic or lo- 26

27 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks calised in the region of the blocks to ated by lumbar medial branches. It is Agents be performed; a concomitant but separate problem to Any conventional local anaesthetic bleeding diathesis, due to their radicular pain. can be used for medial branch blocks. haematological disease or antico- Agents most commonly used are agulants bupivacaine 0.5% and lignocaine 2%. possible pregnancy. Facilities Required Other concentrations that can be used Radiological Equipment are bupivacaine 0.75% and 0.25%, Relative Fluoroscopy is mandatory for the and lignocaine 1% and 4%. Because Relative contraindications are con- conduct of lumbar medial branch of the small volumes used, high con- ditions that do not preclude the con- blocks. The preferred equipment is a centrations should generally be used duct of lumbar medial branch blocks C-arm fluoroscope that allows the x- in order to obtain the most effective but which require special considera- ray beam to be directed at any angle. anaesthetic effect. For medial branch tion because of the risks they pose. In Furthermore, in order to document the blocks, no more than 0.3 ml is required the face of these conditions the inves- accurate placement of needles and the to block the nerve adequately. tigator may elect not to perform medial spread of contrast medium a device Contrast medium is required if the branch blocks, or if they do undertake must be available to obtain either hard- operator wishes to test for intra-vascu- blocks special precautions are required. copy films or an image on specialised lar placement of the block needle. These conditions include, but are not paper. necessarily limited to the following: allergy to contrast media, which Needles, Gowns, Drapes, etc. Preliminary Procedures may require cover with corticoster- A 90 mm, 25 gauge needle is optimal, History and Physical Examination oid and H1 and H2 antagonists; for it is minimally painful when passed A history and physical examination allergy to local anaesthetics, which through the skin and muscles overlying are required to exclude pain likely not may require identification and use the target joint. to be of zygapophysial joint origin and of a class of anaesthetic to which The needle may or may not have a to identify or exclude contraindications the patient is not allergic; Luer lock, but such a lock is preferable. to blocks. Otherwise, a history and concurrent treatment with non- A standard preparation tray may be physical examination are required to steroidal anti-inflammatory medi- used, which comes with cotton balls record baseline data concerning the cations, including aspirin, that may and gauze, but more elaborate trays location and extent of pain, including a compromise coagulation, in which can be custom made to come with visual analogue score, and the move- case, medication may need to be needles and local anaesthetic. ments and activities of daily living that suspended for an appropriate pe- Solutions for skin preparation may are customarily prevented by the pain. riod prior to the conduct of blocks. be an iodine-based solution (e.g., On obtaining this baseline history, Povidone-iodine), chlorhexidine, or al- the patient should be briefed as to how Neurological signs are a relative cohol-based antiseptic (e.g., chlor- their response to blocks will be meas- contraindication for lumbar medial hexidine 0.5% in 70% alcohol). ured. They should be instructed in the branch blocks, inasmuch as the neu- Sterile gloves are used. use of any pain diaries or visual ana- rological disorder should be managed Local anaesthetic agents may be logue scales that might be used. first. If a patient also has back pain, that injected directly from a syringe at- pain could be investigated with medial tached to the spinal needle, or minimal Informed Consent branch blocks once the neurological volume extension tubing may be inter- Informed consent must be obtained. disorder has been managed or is be- posed between needle and syringe, Although medial branch blocks should ing managed. according to operator preference. be safe procedures, like any invasive In that context, radicular pain is not Given that only a small volume of procedure they carry the nominal risk a contraindication for medial branch agent is injected, a 2 ml syringe is all of infection, bleeding and allergic re- blocks, but the investigator should not that is required. action. be under any misapprehension that The patient should be advised that medial branch blocks will relieve radicu- Medications the procedure is a diagnostic one, and lar pain. Medial branch blocks are Intravenous solutions, sedation or should not be confused with a thera- indicated if the diagnostic hypothesis antibiotics are not required. peutic procedure. They should be is that the patients back pain and any advised that they may or may not somatic referred pain might be medi- obtain relief, and that in particular they 27

28 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks should be prepared for no relief ensu- border of the transverse process and that the outline of the scotty dog is ing. They should be advised that ex- the location of the mamillo-accessory clearly evident, the puncture point is pecting any particular result confounds notch. This target point has been shown automatically selected by placing the the purpose of the test, and that they to be least associated with inadvertent tip of the needle on the skin directly in should report the result honestly. spread of injectate into the intervert- line, along the x-ray beam, with the Other than to expect either relief or ebral foramen or epidural space.1 On target point on the eye of the scotty no relief, the patient should not be oblique views, the target point lies high dog. informed of the duration of relief to on the eye of the scotty dog. 1 At the The needle is then passed quickly expect. They should be prepared only L5 level, the target nerve is not the through the skin and slowly through the to the effect that if relief ensues they will medial branch but the L5 dorsal ramus back muscles in a straight line towards need to monitor and record its duration proper. This nerve crosses the ala of the the target point. The progress of the and extent. sacrum in a manner analogous to the needle is monitored by periodic inter- passage of upper lumbar medial mittent screening to ensure that it does Premedication branches across a transverse process. not stray from a direct course to the No premedication is required. For a given lumbar zygapophysial target point. Insertion is terminated joint both of the two nerves that inner- once the tip of the needle strikes bone. vate the joint will need to be anaesthe- This should be high on the eye of the Technique tised. Caution should be taken in label- scotty dog. Preparation ling and recognising the appropriate Correct placement is confirmed by Neither physiological monitoring nor nerves, because the nomenclature of obtaining a postero-anterior view. In intravenous access is required. the nerves and the respective joints is this view the tip of the needle should be out of phase; the joints and nerves do at least opposite the lateral margin of Positioning not take the same segmental numbers. the silhouette of the superior articular Although a posterior approach is The L5-S1 joint is innervated by the process, and preferably slightly me- possible, the most convenient and tech- medial branch of the L4 dorsal ramus dial to this margin. This is because the nically least demanding approach for (which crosses the L5 transverse proc- superior articular process often bulges lumbar medial branch blocks is an ess) and by the dorsal ramus of L5 laterally, overlapping the target point oblique. For this, either the patient lies (which crosses the ala of the sacrum. dorsally. If the tip lies lateral to this prone and an oblique view is obtained The L4-5 joint is innervated by the margin, it has struck the base of a thick by rotating the C-arm of the fluoro- medial branches of L3 and L4 which transverse process instead of the su- scope, or an oblique view is facilitated cross the L4 and L5 transverse proc- perior articular process, the original by the patient lying semi-prone with a esses respectively. Note how the iden- target point having been judged too low pillow under their abdomen to tilt the tity of the joint is numerically the same on the eye of the scotty dog. In target side upwards. as the transverse processes onto which which case, the needle should be re- needles shall be placed, but that the adjusted dorsally, i.e., higher on the Sterility names of the nerves are one segment eye, until correct position is obtained, The skin of the back must be ad- less. and confirmed on PA views. equately prepared as for an aseptic In identifying and recording a target Once the needle is in correct posi- procedure, using one of the solutions point care should be taken to specify tion, the bevel should be directed listed above. The prepared area must whether the segmental numbers refer caudally so as to avoid spread of the be allowed to dry in order to ensure to the joint, the transverse processes injectate to the intervertebral foramen.1 sterility. A fenestrated drape made of or the target nerves; otherwise confu- This having been done, 0.1-0.3 ml of cloth, paper or plastic should be ap- sion will emerge. contrast medium can be injected to test plied to cover the non-sterile areas that venous uptake does not occur. If surrounding the prepared area. Needle Placement it does, the needle must be readjusted For L1-4 Medial Branch Blocks. A by a millimetre or two and the test Target Identification puncture point on the skin is selected repeated. If there is no venous uptake, For the L1-L4 medial branches, the above and lateral to the target point, 0.3 ml of local anaesthetic is injected target point will be at the junction of the usually just above the tip of the target onto the target nerve. Both nerves that superior articular process and the trans- transverse process as seen of AP innervate the target joint are anaesthe- verse process which the target nerve view. However, if an oblique view of the tised in the same way. crosses, midway between the superior target area has been obtained, such 28

29 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks For L5 Dorsal Ramus Blocks. The Reference resumed while pain free. They protocol is the same as for blocks at Dreyfuss P, Schwarzer AC, Lau P, et should record movements and ac- higher levels. The differences are that al. Specificity of lumbar medial branch tivities that they have been able to the target nerve is not the medial branch and L5 dorsal ramus blocks: a com- resume. but the dorsal ramus itself, and that that puted tomographic study. Spine 1997; target point is the junction of the ala of 22: 895-902. the sacrum with the superior articular Evaluation process of the sacrum. This target The singular reason for performing point is recognised on PA views, prima Post-procedural Care diagnostic blocks is to obtain infor- facie, as a notch between these two Upon removal of the needle, the skin mation. That information depends on bones. The target point lies opposite is cleaned to remove the antiseptic and a reliable evaluation of the patients the middle of the base of the superior any blood. A small adhesive patch can response to blocks. Although perform- articular process and hence, slightly be applied to the puncture sites, but is ing the diagnostic block is an essential below the silhouette of the top of the ala probably unnecessary. first step, the block itself does not make of the sacrum. A higher placement is If the patient complains of any unto- the diagnosis. Unless the patients re- associated with spread of injectate into ward side effects following the proce- sponse is carefully evaluated and con- the L5-S1 epidural space, and a lower dure, appropriate action must be taken. trolled for false positive responses, the placement is associated with spread to A common reaction is a vaso-vagal act of performing the block is a waste. the S1 posterior sacral foramen.1 response. This is managed with pulse There are several potential sources A puncture point on the skin is se- and blood pressure observations and of error in the assessment of a re- lected just lateral to the target point so rest in the supine position. Rarely is sponse to a diagnostic block. that the course of the needle will be in any further intervention indicated. M Patients who expect and want a a ventral and medial direction, towards Otherwise the procedure is usually block to work may suffer a placebo the target point, but medial to the adja- well tolerated, and the patient may be response, and obtain or report re- cent iliac crest. Insertion is monitored allowed to dress and await evaluation lief for reasons other than the phar- to ensure that the needle does not stray and discharge. macological effects of the block. over the top of the sacrum. A security Discharge instructions include: M A doctor who expects or wants the in this regard is that, at all times, the tip M to contact the doctor who performed block to work may overtly or sub- of the needle must be below the upper the procedure if there is any unu- consciously coach the patient to margin of the sacrum. sual symptom or pain following the report a positive effect even when Insertion is terminated once the nee- procedure. Fever and tenderness one is not truly achieved. dle strikes bone at the target point. If greater than that which might be M An assessor who wants the block to bone is reached but not precisely at the ascribed to a needle track may be work may exercise observer bias, target point, the needle is readjusted signs of infection. To this end, an and report as positive a block whose until correct position is obtained. Once instruction sheet with a name and effect has not truly been positive, or the needle is in correct position its telephone number is useful. This report as completely effective a bevel is directed to face medially. This sheet should be separate to any block that has been only partially reduces the risk of inadvertent spread other data sheets given to the pa- effective. of injectate to either the L5 interverte- tient. M Blocks may be performed at a time bral foramen or the S1 posterior M to monitor the extent and duration of when the patients pain is minimal, foramen.1 any relief that ensues. To this end or even absent. In that event it is a pain diary is helpful. However, difficult to argue that any supposed Records critical is the time when the pain relief obtained was due to the ef- An image demonstrating the needle starts to return and the time that it fects of the block, and not simply a position must be obtained whenever a returns to its former, accustomed reflection of the patients low level of substance is injected. A plain radio- intensity. pain at the time. graph may be obtained using conven- M if relief occurs, the patient should M If the response to a block is evalu- tional film or specialised paper. Such carefully attempt the movements ated immediately and only upon a record protects the operator in the and activities of daily living that completion of the block, a false event of alleged misadventure. customarily are restricted by pain, impression may arise. Having rested in order to determine whether these during the performance of the block movements and activities can be the patient may obtain relief of the 29

30 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks pain. If asked if there is any relief priate therapy that is destined to fail. It The doctor describes the pain that is upon completion of the block the is therefore, imperative that informa- being targeted by the forthcoming patient will correctly respond that tion based on diagnostic blocks be block, and if appropriate, highlights there has been relief, but when reliable and valid, i.e., free from error. how this pain is distinguished from any subsequently they resume activi- Certain errors can be reduced by other pain that the patient might con- ties of daily living it may become performing diagnostic blocks under currently have. apparent that the block has, in fact, double-blind conditions. When the Both the doctor and the assessor not produced a positive effect. patient does not know which agent is should determine and agree that the M If a patient is discharged following being used, they cannot conform to an patients level of pain is sufficiently completion of a block and their expected response. Simultaneously, intense for any response to the in- response is assessed at some time the double-blind paradigm prevents tended diagnostic block to be credible later, be that by telephone interview the doctor, or an independent asses- and meaningful. or at a subsequent consultation, sor, from coaching the patient as to In this regard, a reasonable guide- they may suffer recall bias. They what response to expect. Unless a line is that the patients present pain may not remember accurately how diagnostic block is performed under should be no less than 50% of their much relief they obtained and for double-blind conditions, the risks of pain at its worst. Serious consideration how long. Furthermore, their report response bias, observer bias, and re- should be given to the propriety of is entirely subjective, no independ- porting bias, remain eminent, regard- proceeding with blocks either in pa- ent trained observer having cor- less of how honest and objective a tients whose typical pain is less than 40 roborated objectively the validity of doctor claims, or insists, they are. The on a 100 mm scale, or in patients their response. elimination of other sources of error whose pain at the time when the block M Although patients in absentia might require other measures, as outlined is to be undertaken is less than or equal be asked to complete a graphic below. to 20 on a 100 mm scale, for the natural record of their pain levels, this proc- diurnal variation in pain may be of this ess is confounded by the patient Towards An Optimal Protocol magnitude; and a decrease in pain by having access to what they previ- At a Master Class conducted by the only 20 points may not be legitimately ously recorded. Guidelines for the International Spinal Injection Society ascribable to the intervention. completion of serial visual analogue at the University of Newcastle in 1998, Separately with the patient, the as- scales for pain maintain that pa- participants discussed the issues raised sessor records baseline measures tients should not see their previous above. They agreed that the signifi- pertaining to the patients pain. entries.1 cance of diagnostic blocks for spinal Separate from the assessor, the M An untutored patient may fail to pain lay in the information obtained, doctor performs the diagnostic block. recognise that a block has been not in the execution of the block. They Once the doctor is satisfied that the successful. This can occur when a recognised the potential sources of block has been adequately and safely patient has multiple sources of pain. error that obtained when blocks were completed, and that the patient has no Although a block may successfully not performed under controlled condi- resulting side effects that require im- anaesthetise one of their sources tions. mediate medical attention, they return of pain it may not relieve other The meeting resolved that the optimal the patient to the registered nurse for sources. Consequently, when means of reducing error and securing assessment and evaluation. The doc- asked, in absentia, if their pain was reliable diagnostic information was tor takes no part in this evaluation, and relieved the patient, having not ob- real-time assessment. Under this is free to continue with other patients. tained total relief of all of their pain, protocol, the response to a diagnostic The assessor evaluates the patients may report that it wasnt. block is evaluated immediately after response to the block, administering the block, and for some time after- the instruments that have been se- Such errors have potential ramifica- wards, at the clinic at which the block lected for this purpose. (See Schedule tions with respect to both medicolegal was performed, and by an independ- A, below.) proceedings and treatment. Blocks ent observer using validated and ob- The assessment continues in princi- subject to error may lead to false jective instruments or tools. ple for the duration of the patients conclusions about the veracity of a Under the protocol, the doctor who is response to the block, or until the source of pain. Liability, therefore, to perform the diagnostic block intro- effects of the block have been reason- may subsequently be misattributed. A duces the patient to an independent ably established beyond doubt. false conclusion may lead to inappro- observer, typically a registered nurse 30

31 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks M If the patients pain has not been relieved, the patient can be pre- the doctor who should review it. The doctors responsibility in this regard is Schedule A. pared for discharge once it has been clearly established that there to ensure that the assessment has been properly conducted and thor- Instruments for As- has been no relief. M If the patient reports relief, this oughly recorded. The doctor cannot dispute the assessment. They can, sessing Response should be monitored and corrobo- however, identify whether there has A variety of instruments might be rated by the assessor for at least been any misinterpretation, for exam- used to assess the effects of a diagnos- two hours or until the effects of the ple if the patient and the assessor both tic block. There is a risk however, of local anaesthetic agent wear off, misconstrued which of a patients sev- overloading a patient with enquiries, whichever is the sooner. If possible eral pains was targeted by the block questionnaires, and other tools. A prag- logistically, the relief should be moni- undertaken. Any corrections to the matic approach is to use three instru- tored for longer. In this regard, the record in this regard should be de- ments. period of two hours is nominated as scribed in narrative. In order to avoid a minimal period that seems prac- ambiguity, misinterpretation, or mis- M Relief of pain can be recorded by ticable in general. Patients who representation, the original assess- using serial visual analogue scales. need to travel or who need to return ment form should not be amended; M Relief of disabilities can be re- to work or to other duties may find instead, a revised assessment form corded by having the patient nomi- it inconvenient to remain for a longer should be appended to the original nate four, or as many as possible, period. form, along with an explanation of why activities of daily living that (1) are and how the revision was undertaken. impeded or prevented by their pain; The patients response should be Once the doctor has reviewed the (2) which are likely to be restored, recorded independently by the asses- assessment, the patient can be dis- or should be restored, if the pain is sor at prescribed periods. A reason- charged. relieved; (3) and which can practi- able schedule is to record the level of Subsequently, the assessor should cally be assessed in a clinic setting. pain before the block, immediately review the patient in order to determine (Examples might include bending, after the block, 30 minutes after the and record the patients longer-term lifting, turning, sitting, walking. Im- block, and hourly thereafter. The as- response to the block. This could be practical examples include return sessment of pain should be comple- done by telephone interview on the to work, sleeping, and having sex.) mented by an assessment of any im- following day. This review should record To this end, the assessor should provement of disabilities, and by a the ultimate duration of any positive record the nominated activities narrative description of either how the effect of the block, in terms of when the before the execution of the block, patient feels about the relief obtained, patients pain returned, how they felt and observe and note the demon- or any difficulties that they may have during the period of relief, and any side strated degree of disability. After concerning the response. The narra- effects or reservations about the ef- the block, and repeatedly through- tive serves to corroborate the response fect. The use of telephone enquiry out the period of assessment, these inferred from the visual analogue does not offend the reservation out- disabilities should be assessed and scores for pain. When a patient scores lined above about recall bias, because the degree of restoration recorded. zero on the VAS but is not pleased by the patients primary response has M To corroborate the assessors the effects of the block, doubts can be already been recorded. The telephone record of the assessment, a power- raised about the effectiveness of the enquiry simply obtains supplementary ful tool is to videotape the patient block. Conversely, the assessor can information concerning the patients executing activities before and af- be more confident in the response if subsequent course and welfare. ter the block. Such a record could the patient reports feeling the best that also include the patients mood and they have felt in years, or other such Reference facial expression. descriptions. Reciprocally, a patient Carlsson AM. Assessment of chronic who verbally reports that they obtained pain. I. Aspects of the reliability and Appendix A, shows an example of a complete relief but fails to indicate that validity of the visual analogue scale. form that succinctly records an as- on their visual analogue scale should Pain 1983; 16: 87-101. sessment. explain the discrepancy. Once the assessor has completed Interpretation the assessment it should be reported to A positive response to a block is, 31

32 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks prima facie, one in which there is corresponds to the pattern for a par- relieves the upper region of the pa- complete relief of that part of the pa- ticular segmental level, tients pain, a second block relieves the tients pain which the blocks might be M the two nerves on each side of the complementary region of pain, and the expected to relieve, for a duration same segment may be blocked, or third, confirmatory, control block can commensurate with the expected du- M the patient could be assessed as if address all levels at once. A staged ration of action of the local anaesthetic they have two pain sources, one on procedure in this manner, secures a used. Partial reduction of that pain each side, and each side is ad- valid diagnosis. It avoids wrongly pre- does not constitute a positive response. dressed systematically but inde- suming, ab initio, that the pain is me- The only exception can be that the pendently. diated by multiple, consecutive nerves, patients accustomed pain is com- and blocking all of those nerves. Doing pletely relieved but they complain of If controlled blocks on each side so may lead to false positive results pain from the needle track, which would relieve the pain on their respective when more nerves are incriminated not be relieved by a medial branch sides, a subsequent block may be than warranted. block. undertaken simultaneously bilaterally, How these various combinations can If the patients pain is mediated by if it is necessary to show that all of the be accommodated efficiently, using the nerves anaesthetised, they should patients pain can be relieved at the the minimum number of procedures is obtain complete relief of their pain. one time. address below under An Algorithm for If the patients pain is mediated by If blocking one side relieves all of the the Investigation of Back Pain. nerves other than the ones anaesthe- patients pain bilaterally, there is no tised, they should obtain no relief of need to proceed with investigation of Performance Parameters their pain. the opposite side. Although experienced and expert If the patients pain is mediated by The latter approach is intellectually operators may be more efficient and several nerves, including but more more efficient and less subject to di- faster than the following standards re- than the ones anaesthetised, the pa- agnostic noise, for it allows the dem- quire, the parameters that define a tient will obtain relief of that part of their onstration of bilateral pain stemming minimum level of competence and pro- pain that is mediated by the nerves from just one side, if that is the case. ficiency for the performance of lumbar anaesthetised, but no relief of pain However, in some settings it might not medial branch blocks are: mediated by the other nerves. Exam- be practical or convenient for the pa- M not more than eight adjustments or ples include: tient to return for systematic investiga- corrections of the course of the M in a patient with bilateral pain, if only tion, in which case it might be prefer- needle from insertion to reaching the left side is blocked, the pain on able to block both sides of an appar- the target point; that side will be relieved but the pain ently unisegmental pain simultaneously; M not greater than 1.5 minutes total of the other side will not be relieved. or, once a single block on each side radiation exposure time to block a M in a patient with pain mediated by has been found to relieve the pain on given nerve, which includes expo- three consecutive nerves, if only the the respective side, a confirmatory sure time to identify the target point upper two are blocked, the patient block may be undertaken simultane- and puncture point, prior to inser- may obtain relief of the upper part of ously on both sides. tion of the needle. their pain, but no relief of the lower If the diagnostic hypothesis is that part. The converse applies if the lower nerves are blocked. the patients pain is mediated by mul- tiple, consecutive medial branches, An Algorithm for the Such responses nevertheless con- and if they obtain relief of the upper half of their pain when the upper nerves are Investigation of stitute a positive response, for the pain targeted by the blocks was completely blocked, it should transpire that block- ing the lower nerves will relieve the Back Pain relieved. The responses may be partial lower half, but not the upper half, of Introduction topographically but they are complete their pain, and all of their pain should The following algorithm for the inves- physiologically, in the targeted area. be relieved when all nerves responsi- tigation of low back pain is based on the In the event of such responses, a ble are blocked. Although it takes one best available evidence on the epide- comprehensive or systematic ap- more procedural session than it does miology of various identifiable sources proach may be undertaken for a com- to diagnose a unisegmental pain, it is of chronic low back pain, and is de- plete and accurate diagnosis. preferable to diagnose multi-level pain signed to promote the efficient use of If the patients pain is bilateral and as a staged procedure. The first block invasive investigations. It is not de- 32

33 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks NAME OF PRACTICE OR INSTITUTION DIAGNOSTIC BLOCK EVALUATION SHEET: LUMBAR BLOCKS PATIENTS NAME:... DOB: .././. PROCEDURE:.. DATE://. DOCTOR:.. ASSESSOR:. DESCRIPTIONS PAIN MAP INDEX PAIN: CONCURRENT PAIN:. .. .. INSERT BODY CHART .. OF LUMBAR SPINE AND FOUR ACTIVITIES LIMITED BY INDEX PAIN: LOWER LIMBS 1:... 2:... 3:... 4: VAS: Worst pain ever experienced: /10 Worst ever index pain: /10 Index pain today: /10 RESPONSE: ADLs RESTORED: 1 2 3 4 PATIENTS REMARKS:.. 100 .. 90 .. 80 .. V 70 .. ASSESSORS REMARKS: A 60 .. S 50 .. 40 .. 30 .. 20 .. 10 .. CORRECTIONS/ COMMENTS 0 .. Pre Post 30m 1hr 90m 2hr 3hr 4hr .. INTERPRETATION OF RESPONSE: PLAN OF ACTION .. .. .. .. SIGNED: DOCTOR . ASSESSOR: DATE: // /../. Appendix A: Example of Forms Suitable for Real-time Assessment 33

34 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks signed to achieve a diagnosis in every out fear of missing an undisclosed or There may, however, be reasonable patient. Indeed, the algorithm contains unsuspected serious condition. cause to test for a diagnosis of several nodes that call either for a The second step requires a decision discogenic pain even though treat- cessation of investigations or for care- as to whether the intervertebral discs ment is not available. Establishing a ful reconsideration of the propriety to are pristine. The purpose of this deci- diagnosis of discogenic pain may pre- proceed. the algorithm is based on the sion is to direct investigations to or vent the futile pursuit of other diag- principles that: away from the intervertebral discs. noses. The algorithm permits the use M once an ambiguous or contradic- Although discogenic pain can arise of discography for such purposes but tory result has been encountered, from discs that are normal on MRI this calls for an active and conscious con- it is wasteful of resources to venture is uncommon.1 In the interests of effi- sideration of this indication. to correct, overcome, or reverse ciency, therefore, it is recommended If reasonable and appropriate treat- that ambiguity by repeating proce- that investigations of the disc not be ment is available, the discs should be dures. undertaken in the first instance in pa- investigated. This recommendation is M the resources of a physician are tients with normal discs on MRI. Al- based on the best available evidence better committed to investigating though this ostensibly disenfranchises which indicates that amongst patients new patients who have a greater the few patients who might have with chronic low back pain, internal likelihood of obtaining a diagnosis discogenic pain but with normal discs, disc disruption is the single most com- than pursuing a diagnosis in pa- the recommendation is critical. With- mon cause; it accounts for at least 40% tients in whom ambiguous or spuri- out it, the absurd situation arises in of cases, and is far more prevalent ous results have been encountered. which every patient becomes entitled than any other identifiable condition.2,3 to undergo discography. Because of In a patient with abnormal discs on In this regard, cardinal amongst the the low yield of discography in patients MRI, internal disc disruption is the resources that can be so squandered with normal discs, this constitutes a most likely diagnosis, and in the inter- are the skills and time of the physician waste of resources. Physicians con- ests of efficiency should be the diag- who undertakes the investigations. cerned about their patients with normal nosis first pursued. It constitutes a Otherwise, the algorithm is designed discs being disenfranchised are nev- waste of effort and resources to under- to provide a disciplined approach to ertheless free to make a case for take other investigations only to prove the use of invasive investigations for investigating the discs of these pa- them negative in patients in whom lumbar spinal pain, and to avoid hap- tients. For the most part, however, it is those other investigations were never hazard behaviour or investigations inefficient to do so. likely to be positive. being undertaken essentially at the If on MRI the intervertebral discs are Disc stimulation and CT-discogra- whim of a physician. In this regard, the normal, it is unlikely that the patient will phy is the only established means of algorithm is predicated by the pre-test have discogenic pain, but reciprocally pursuing discogenic pain. The tech- probabilities of various conditions, and it is more likely that they have some niques involved have been described invites investigation of the more com- other source of pain. Therefore, the in the literature,1 and criteria for a mon conditions first, rather than pur- pre-test likelihood of pain from one or positive diagnosis have been estab- suing any condition arbitrarily. other of the synovial joints of the lumbar lished.2,4 spine and sacrum becomes greater If the results of disc stimulation are than base rates. Accordingly, the algo- negative, discogenic pain is excluded. Part 1: Discogenic Pain rithm invites investigation of the syno- If discogenic pain is excluded, the The algorithm commences with and vial joints. question should be raised as to whether requires an MRI of the lumbar spine. If on MRI one or more of the lumbar further pursuit of a diagnosis is justi- This serves two purposes. discs is abnormal, the decision to fied. This decision relies on the judge- First it provides a screening test for investigate should be predicated on ment, inclination, or intuition of the red flag and exotic causes of back whether reasonable and appropriate physician involved. If further pursuit is pain, such as tumours, infections, and treatment is available, should the in- not justified, investigations cease. Oth- metabolic disorders. Because of the vestigation of the discs prove positive. erwise, the algorithm allows the patient high sensitivity of MRI, not only will The investigation of discogenic pain, to be investigated for sources of pain such a screening test detect these using presently available techniques, amongst the synovial joints of the lum- rare conditions, it will also exclude is potentially harrowing for the patient, bar spine and sacrum. them. That being the case, invasive and carries a risk, albeit very low, of If the results of disc stimulation are investigations can be undertaken with- infection. not negative, they may be indetermi- 34

35 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks Algorithm Part 1: Discogenic Pain 35

36 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks nate, i.e., not convincingly positive. bilateral back pain are unlikely to have the diagnosis of sacroiliac joint pain is This pertains to situations where many bilateral sacroiliac joint pain. They are established. or all discs are positive to stimulation, more likely to have bilateral If the confirmatory block is negative, or when no control disc is negative. zygapophysial joint pain. Therefore, a conundrum arises. Either the first Under these circumstances the algo- the algorithm asks whether there is block was false positive, or the second rithm recommends cessation of inves- good reason to believe that the patient block was false negative. Since this tigations. The patient may have might have bilateral sacroiliac joint conundrum cannot be resolved without discogenic pain, possibly at multiple pain. The expected, default answer is multiple, repeated investigations, the levels. In that event, however, there is no, and the algorithm proceeds to algorithm recommends cessation of no valid treatment that might responsi- assessment of the zygapophysial joints. investigations, with the diagnosis re- bly be prescribed. If the painful disc Nevertheless, the algorithm does allow maining indeterminate. cannot be confidently identified, it for consideration of bilateral sacroiliac Before allowing zygapophysial joint cannot be targeted for treatment. If joint pain. blocks the algorithm asks if the patient multiple discs are painful, there is at The third question of the algorithm is is negative to Revels tests.7 These present no dependable treatment for whether the patients pain is entirely tests do not establish that the patient multi-level discogenic pain. On the caudal to the L5 level of the lumbar has zygapophysial joint pain, but they other hand, the patients response may spine. The basis for this question is that do increase the likelihood to a modest be false positive. In that event, the in patients proven to have sacroiliac degree. The tests, however, are es- indeterminate result constitutes a cue joint pain, in all instances the pain is sentially negative in nature. They re- that any additional or further investiga- perceived caudal to the L5 level. Con- quire the absence of certain features. tions may also be liable to false positive versely, no patient with proven sacro- If any of the tests are positive, the results. Since there are no valid means iliac joint pain has been described who likelihood of zygapophysial joint pain of overcoming this possibility, the algo- had pain extending above the L5 level.6 drops. The algorithm requires careful rithm recommends cessation of inves- Pain below L5 does not necessarily reconsideration of the propriety of tigations. implicate the sacroiliac joint as the summarily proceeding to zygapoph- If the results of disc stimulation are source,6 but pain above L5, renders ysial joint blocks in a patient who does neither negative nor indeterminate, by sacroiliac joint pain unlikely, and by not satisfy Revels criteria.7 In that definition they will be positive. In that implication, promotes the likelihood of event, the likelihood of obtaining a event a diagnosis of discogenic pain zygapophysial joint pain. Conse- positive result from blocks is low. To will have been made, and if the appro- quently, this third question is pivotal to proceed with blocks should be justified priate morphological features are evi- the efficiency of the algorithm. It is on grounds greater than a guess or a dent on CT-discography, the diagno- worth pursuing sacroiliac joint pain if whim. sis may be internal disc disruption. the pain is entirely caudal to L5, but not If a patent is negative to Revels tests, if it extends above L5. their zygapophysial joints can be in- Part 2: Synovial Joint Algorithm In the event that the patients pain vestigated. The algorithm for investigating the does not stem from the sacroiliac joint, synovial joints of the lumbar spine and that will be established at the expense Part 3: Zygapophysial Joint Blocks sacrum, commences with a set of of only one block. It is more efficient, The zygapophysial joints are enter- clinical questions. The first is whether therefore, to exclude the sacroiliac tained last in the algorithm because or not the patients pain is located in the joint in the first instance, than to ex- they are the least likely sources of very midline. The available evidence clude or pursue zygapophysial joint chronic back pain in the working age indicates that patients with this sort of pain, for the latter may require multiple population, with a prevalence of less back pain defy the investigations en- investigations. than 15%,5 and probably closer to only compassed by this algorithm.1,5 The If the patients pain is entirely caudal 10%. yield from zygapophysial joint blocks to L5, a sacroiliac joint block should be Different figures, however, apply to or from disc stimulation is essentially undertaken. an older population without a history of nil. Therefore, the algorithm invites If the block is negative, the patient is injury. In those patients the pre-test reconsideration of the propriety of considered for zygapophysial joint likelihood of zygapophysial joint may pursuing investigations, and implicitly blocks. be 40% or higher.8 In that population, recommends that they cease. If the block is positive, a confirma- zygapophysial joint blocks become a Whether the pain is bilateral is an tory block should be undertaken. prime investigation, ahead of disc intermediate question. Patients with If the confirmatory block is positive, stimulation, and possibly ahead of 36

37 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks Algorithm Part 2: Synovial Joint 37

38 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks sacroiliac joint blocks. should, therefore, have good cause to tised, so as to reproduce and confirm The low prevalence of lumbar suspect this joint, lest they perform the effect of the original screening zygapophysial joint pain predicates investigations that prove that it is not block. the design of the algorithm. Because painful. If the response to the control block is zygapophysial joint pain may arise If at any time a block is positive, it positive, the diagnosis of two-level pain from any of a number of segmental should be followed by a confirmatory is confirmed. levels, multiple investigations may be block. If the response to the control block is required to detect a symptomatic joint. If that confirmatory block is negative, negative, the patients responses to However, the low prevalence of this investigations should cease. A nega- blocks should be carefully reconsid- condition means that the majority of tive response raises a conundrum. ered, for their responses to blocks are such investigations will be negative Either the first block was false positive, inconsistent with two-level pain. Their and fruitless. It, therefore, becomes or the second block was false negative. responses to blocks may have been inefficient to pursue zygapophysial Since this conundrum cannot be re- false positive. joint pain, one joint at a time, only to solved without undertaking multiple exclude all joints in the majority of further blocks, the algorithm recom- Part 4: Efficiency cases. For this reason the algorithm mends cessation of blocks, with the Under the operation of this algo- recommends a multi-level screening diagnosis remaining indeterminate. rithm, discogenic pain is excluded or test. If the confirmatory block is positive, confirmed within one step. Sacroiliac The virtue of a screening test is its a diagnosis of zygapophysial joint pain joint pain is excluded within one block, negative predictive value. If the likeli- is established. or confirmed within two blocks. hood is that the majority of patients will If at any time a block of a single joint In patients in whom sacroiliac joint not have zygapophysial joint pain, it is or of both joints at a single segment is pain is not suspected, zygapophysial efficient to establish this expeditiously. partially positive, in that it provides joint pain is excluded within one step - Not only are resources conserved but complete relief of pain but only in part a screening block, or diagnosed within the patient does not need to suffer of the patients region of pain, yet the four steps: one screening block that is repeated invasive tests in vain. patient responded to multi-level screen- positive; one or two blocks at single At a single sitting, both joints at L4-5 ing blocks, the response indicates levels to pinpoint the responsible joint; and L5-S1, bilaterally if indicated, can zygapophysial joint pain at multiple and one confirmatory block. be anaesthetised. If the patient can levels. In that event, the next most likely In patients in whom sacroiliac joint tolerate the additional steps required, joint should be blocked, in an effort to has been entertained but excluded, the L3-4 joints can be added. relieve that part of the patients pain zygapophysial joint pain is excluded If the result of this screening test is that was not relieved by the previous, within two steps: the negative sacro- negative, zygapophysial joint pain will single-level block. iliac block, and the negative screening have been excluded, and investiga- If the response to the block of the block for zygapophysial joint pain. tions can cease. second level is negative, the patients Zygapophysial joint pain is established If the result of the screening test is responses to blocks should be care- within a total of five steps: one to positive, zygapophysial joint pain is fully reconsidered, for their responses exclude sacroiliac joint pain, one implied, but its exact source is not to screening blocks are not concord- screening block to implicate evident. That requires anaesthetising ant with their responses to blocks at zygapophysial joint pain, one or two joints one at a time. single levels. Their response to screen- blocks to pinpoint the responsible joint; The algorithm recommends com- ing blocks may have been false posi- and one to confirm the response. mencing arbitrarily at L5-S1 in order to tive. Given the pre-test probabilities that pinpoint the exact joint that is the source If the response to the block of the M internal disc disruption accounts of pain. second level is positive, in that it re- for 40% of cases of chronic low If blocks of L5-S1 are negative, the lieves that part of the patients pain that back pain; L4-5 joint should be considered and was not relieved by the first block, a M sacroiliac joint pain accounts for up blocked. diagnosis can be entertained prima to 20% of cases; and If L4-5 blocks are negative, the ques- facie that the patient has two-level M zygapophysial joint pain accounts tion is posed whether it is reasonable zygapophysial joint pain. That diagno- for 10%; to suspect or to test L3-4. The basis for sis can then be confirmed with a con- most patients under the algorithm this question is that L3-4 is an uncom- trol block in which both symptomatic would undergo investigations of their mon source of pain.5 The physician levels are simultaneously anaesthe- discs, with 40% proving positive and 38

39 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks requiring no other investigations. Of 1994; 19: 1132-37. the 60% remaining, not all will require 6. Dreyfuss P, Michaelsen M, Pauza sacroiliac joint blocks, but perhaps half K, et al. The value of history and will prove positive, and will not require physical examination in diagnosing zygapophysial joint blocks. sacroiliac joint pain. Spine 1996; 21: Zygapophysial joint blocks will there- 2594-2602. fore be indicated in perhaps only 30% 7. Revel M, Poiraudeau S, Auleley GR, of the original population. Perhaps half et al. Capacity of the clinical picture to of these will prove negative on screen- characeterise low back pain relieved ing blocks. Only the remaining half by facet joint anesthesia. Proposed should be subjected to multiple tests of criteria to identify patients with painful the zygapophysial joints. facet joints. Spine 1998; 23: 1972-77. Accordingly, 9. Schwarzer AC, Wang S, Bogduk N, M in about 30% of cases sacroiliac et al. Prevalence and clinical features joint pain will be diagnosed within of lumbar zygapophysial joint pain: a one block plus a confirmatory block; study in an Australian population with M in about 15% of cases investiga- chronic low back pain. Ann Rheum tions will exclude sacroiliac joint Dis 1995; 54: 100-106. pain and zygapophysial joint pain within two blocks; M only 15% of cases may require up to four or five blocks to pinpoint a painful zygapophysial joint. References 1. Bogduk N, Aprill C, Derby R. Dis- cography. In Spine Care, Volume One: Diagnosis and Conservative Treat- ment ed AH White. St Louis: Mosby, 1995. Pp 219-38. 2. Schwarzer AC, Aprill CN, Derby R, et al. The prevalence and clinical fea- tures of internal disc disruption in pa- tients with chronic low back pain. Spine 1995; 20: 1878-83. 3. Bogduk N, Barnsley L. Back Pain and Neck Pain: An Evidence-Based Update. In Pain 1999 - An Updated Review. Refresher Course Syllabus ed M Max. Seattle: IASP Press, 1999. Pp 371-77. 4. Merskey H, Bogduk N (eds). Clas- sification of Chronic Pain. Descrip- tions of Chronic Pain Syndromes and Definition of Pain Terms. 2nd ed. Seattle: IASP Press, 1994. 5. Schwarzer AC, Aprill CN, Derby R, et al. Clinical features of patients with pain stemming from the lumbar zygapophysial joints. Is the lumbar facet syndrome a clinical entity? Spine 39

40 Australasian Musculoskeletal Medicine November 2001 Lumbar Medial Branch Blocks Algorithm Part 3: Zygopophysial Joint Blocks 40

41 Australasian Musculoskeletal Medicine November 2001 Australasian Faculty of Musculoskeletal Medicine Practice Standards and Protocols: Cervical Medial Branch Blocks Definition involve a single pass of a needle, lars, whereas the dorsal rami had to be C ervical medial branch blocks with little adjustment, whereas with targeted near the intervertebral are a diagnostic procedure intra-articular blocks, difficulties foramen and spinal nerve. designed to test whether a may be encountered with entering The first report of the diagnostic patients pain is mediated by one or a narrow joint-space. Moreover, utility of cervical medial branch blocks more of the medial branches of the medial branch blocks can always was in the context of headache. In cervical dorsal rami. They involve be performed, whereas osteophytes 1985, Bogduk and Marsland6 reported anaesthetising the target nerve with a may preclude entry into a joint. complete relief of headache in eight tiny volume of local anaesthetic in an M medial branch blocks are safer out of 12 patients following anaes- effort to relieve pain. inasmuch as bone prevents the thetisation of the medial branch of the By convention, and on the basis of over-penetration of the needle into C3 dorsal ramus, the third occipital theoretical argument,1 but not on the the spinal canal, whereas it is pos- nerve. An earlier report, but published basis of explicit, objective evidence, sible for a needle to pass through a later in 1986, described relief in seven cervical medial branch blocks are used target joint into the spinal canal and out of 10 of the same patients.7 The to test whether a patients pain stems spinal cord. first report of medial branch blocks at from a given cervical zygapophysial M medial branch blocks are more all cervical levels appeared in 1988. joint. For that purpose, the nerve or easily subjected to controls, in that Bogduk and Marsland8 reported relief nerves that innervate the joint are the target nerves can be anaesthe- of neck pain and headache, or neck anaesthetised. tised with different agents whose pain and shoulder pain, in 17 out of 24 This convention is based on the duration of effect on peripheral patients, following diagnostic blocks of argument that, of all the structures nerves is known, whereas the dif- the C3 or lower medial branches. They innervated by the medial branches of ferential effect of different agents also published maps of the distribution the cervical dorsal rami, the inside joints is not known. of the pain relieved. These maps sug- zygapophysial joints are the only ones M intra-articular blocks, if positive, gested a consistent segmental pattern. that might harbor a discrete, focal lacked a valid subsequent treat- Although never published, doubts source of chronic pain.1 No pathology ment. and reservations were expressed con- capable of producing chronic pain is M intra-articular blocks, therefore, cerning the implications of these stud- known to affect the segmentally spe- lacked therapeutic utility and pre- ies. Prevailing wisdom maintained that cific muscles innervated by the dorsal dictive validity. the cervical zygapophysial joints could rami. Because the ensuing term is M medial branch blocks, if positive, not be a source of pain, and that shorter and more obvious in meaning, could be followed by radiofreq- studies in patients with neck pain were cervical medial branch blocks can be, uency neurotomy. unreliable. This prompted studies in and have been referred to as (one of M medial branch blocks, therefore, normal volunteers to determine whether the means of achieving) zygapophysial had therapeutic utility and predic- these joints could be a source of pain, joint blocks. tive validity. and epidemiologic studies to deter- mine whether zygapophysial joint pain Historical Background Nerve blocks for the investigation of was no more than a rare, idiosyncratic The conduct of cervical medial branch neck pain were first suggested in 1980 phenomenon. blocks arose for the investigation of by Sluijter and Koetsveld-Baart2 who Dwyer et al9 stimulated the cervical neck pain as an analogue of use of advocated blocking the cervical dorsal zygapophysial joints in normal volun- lumbar medial branch blocks in the rami near their origin. Others in Eu- teers by distending the joints with injec- pursuit of back pain. The investigation rope adopted this procedure.3,4 tions of contrast medium. They found of cervical zygapophysial joints as a Based on anatomical studies of the that the referred pain patterns from possible source of neck pain was origi- branches of the cervical dorsal rami individual joints followed a distinctive nally performed using intra-articular and the innervation of the cervical segmental pattern. In a companion blocks of these joints. However, intra- zygapophysial joints, Bogduk advo- paper, Aprill et al10 found that the pain articular blocks were progressively cated a more selective approach by patterns could be used to predict the supplanted by medial branch blocks targeting the medial branches of the segmental location of painful joints. because: dorsal rami, rather than the dorsal rami Later, Fukui et al11 used intra-articular M medial branch blocks are relatively themselves.5 The medial branches injections and electrical stimulation of easier to perform and therefore could be targeted easily and safely medial branches to confirm the seg- more expedient inasmuch as they where they crossed the articular pil- mental patterns. 41

42 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks Bogduk and Aprill12 performed vari- identified and defined four patterns of on a single block, therefore, could not ous investigations in 318 consecutive response: be relied upon to secure a correct patients with neck pain, and found the Concordant: in which patients ob- diagnosis. This result foreshadowed prevalence of cervical zygapophysial tained long-lasting relief following the critical need for controlled blocks in joint pain to be at least 25%. Because bupivacaine but short-lasting relief fol- every patient who underwent diagnos- not all patients underwent blocks of lowing lignocaine, with relief in both tic blocks. these joints, the possibility existed that instances lasting not longer than the A later paper15 tested the validity of the prevalence of zygapophysial joint expected duration of action of the comparative local anaesthetic blocks pain was even higher. agent used. by comparing diagnoses made on the In 1991, Barnsley, later joined by Prolonged concordant: in which pa- basis of comparative blocks with those Lord, commenced a systematic series tients obtained longer-lasting relief fol- based on placebo-controlled blocks. It of investigations of the validity and lowing bupivacaine than that following established that the criteria for con- utility of medial branch blocks. They lignocaine, but the duration of relief cordant and prolonged concordant showed that cervical medial branch with either or both agents exceeded the responses, when combined, had a blocks had face validity, i.e., they were expected duration of action of the sensitivity of only 54% but a specificity target specific.1 Material injected onto agent used. of 88%. This meant that a diagnosis the target nerves consistently bathed Discordant: in which relief following based on a concordant response to the location of the nerve, and did not lignocaine was longer than that follow- comparative blocks was very unlikely spread in a manner so as to affect any ing bupivacaine, but relief in either to be false, but that not all patients with other structure that might be an alter- instance was within the expected dura- zygapophysial joint pain would be cor- native source of pain or to any other tion of action of the agent used. rectly detected if these criteria were nerve that might be mediating the pa- Discordant prolonged: in which re- applied. Many patients who were not tients pain. Specifically their studies lief following lignocaine was longer placebo responders had discordant refuted the criticism that medial branch than that following bupivacaine, but responses. Consequently, for research blocks anaesthetised non-specific relief following either agent was longer purposes, the criteria for concordant muscle spasm, or that they anaesthe- than the expected duration of action of responses to comparative blocks were tised the spinal nerves or their roots. the agent used. robust and would not overestimate the Next they addressed the construct Discrepant: in which patients failed prevalence of cervical zygapophysial validity of cervical medial branch blocks. to obtain relief when the same nerves joint pain. For clinical purposes, the All previous studies had used single were blocked on a second occasion. criteria could be relaxed, if desired, to diagnostic blocks, which did not con- include patients with discordant re- trol for false positive responses, i.e., In order to sustain a sound epide- sponses provided that they obtained placebo responses. Construct validity miologic argument Barnsley et al13 complete relief of their pain whenever requires that diagnostic blocks cor- considered only concordant and con- the medial branches were anaesthe- rectly discriminate true responses from cordant prolonged to constitute a true- tised, regardless of the agent used and false responses, at least to an accept- positive response. Even with this re- regardless of the duration of relief able level of statistical certainty. To this striction, they found a high prevalence obtained. In the event of the latter, the end, Barnsley et al13 tested a para- of positive responses, which was ex- sensitivity of the criteria increases but digm of comparative local anaesthetic tremely unlikely to have occurred by the specificity drops to 65%. In other blocks that had been advocated in the chance alone, i.e., by the patients words, a diagnosis based on discord- pain medicine literature, but promoted having guessed which agent they re- ant responses detects more patients on the basis of theory alone. The ceived on each occasion. Not only did as positive, and is more often correct paradigm maintained that a placebo this validate the paradigm of compara- than it is not, but does have a substan- response could be identified or ex- tive local anaesthetic blocks, it sug- tial chance of being wrong. cluded by repeating the same diag- gested that the prevalence of cervical Three epidemiologic studies fol- nostic block with local anaesthetic zygapophysial joint pain might be high. lowed. The first two used comparative agents with different durations of ac- In a contemporary paper, Barnsley blocks under double-blind conditions tion. Under double-blind conditions, et al14 demonstrated that single diag- to determine the prevalence of cervical Barnsley et al13 performed cervical nostic blocks were not valid. A large zygapophysial joint pain in consecu- medial branch blocks in patients with proportion of patients who responded tive patients presenting with chronic neck pain, using lignocaine and to an initial block failed to respond to a neck pain after whiplash. The first bupivacaine in a random manner. They subsequent block. A diagnosis based focussed on patients with headache,16 42

43 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks and found that, overall, the prevalence anaesthetising the joint. Moreover, it The development of the theory and of headache stemming from the C2-3 showed that very few patients obtained practice of cervical medial branch zygapophysial joint was 27%, but that gratifying relief for longer than a few blocks has attracted recognition be- in patients in whom headache was the days, regardless of the agent used. yond just publication in peer-reviewed dominant symptom, this prevalence Intra-articular steroids did not provide journals. was 53%. The second study17 re- a therapeutic answer to zygapophysial M The early work on third occipital ported 50 consecutive patients with joint pain. headache6 was awarded the Prize neck pain after whiplash. It included In a pilot study, Lord et al21 assessed for Best Poster at the 2nd Interna- some patients from the first study but the efficacy of percutaneous tional Headache Congress in 1985. focussed on neck pain as well as radiofrequency neurotomy, in which M The work on pain patterns in normal headache. It found a prevalence of the medial branches to a painful volunteers9 was awarded the Prize zygapophysial joint pain of 54%. The zygapophysial joint are coagulated to for Outstanding Cervical Spine joints most commonly involved were stop the pain. They found that results Research by the Cervical Spine those at C2-3 and at C5-6. The third were poor when the third occipital Research Society in 1988. study,18 used placebo-controlled diag- nerve was targeted, and they recom- M The controlled study of nostic blocks and focused exclusively mended a moratorium on third occipi- radiofrequency neurotomy22 was on neck pain. It reported the results of tal radiofrequency neurotomy until awarded the Research Prize of the blocks at levels below C3. In 68 pa- better techniques were developed. Spine Society of Australia in 1996. tients, not previously reported, it found However, for neurotomy at lower cer- M For her collection of studies, Dr a prevalence of cervical zygapophysial vical levels, they found encouraging Lord received the Research Prize joint pain of at least 49%, with the results. This prompted a randomised, of the International Association for possibility that it could be as high as double-blind, placebo controlled the Study of Pain at the World Pain 60%. study.22 This established beyond doubt Congress in 1999. Collectively these studies showed that cervical medial branch neurotomy not only that cervical zygapophysial was not a placebo, and suggested that This international recognition by the joint pain was common, but that it was 70% of patients could obtain complete scientific community stands in con- the single most common basis for relief of their pain if treated by this trast to reservations still maintained, chronic neck pain after whiplash. These procedure. Furthermore, the study but never publicly published, by insur- results implied that physicians who did established the therapeutic utility and ance companies and their advisers. not employ zygapophysial joint blocks predictive validity of cervical medial Those reservations do not involve sci- in the investigation of their patients branch blocks. Patients who obtained entific criticism but constitute social risked missing a valid diagnosis in over complete relief from controlled diag- rhetoric. 50% of cases. nostic blocks of the cervical medial Cervical medial branch blocks are A later study, found a much higher branches stood a good chance of condemned privately to patients and prevalence in a specific subgroup of obtaining complete relief of their pain their treating doctors as procedures patients.19 Amongst drivers in motor if the same nerves were coagulated. that have not been embraced by main- vehicle accidents injured at high A later study23 indicated that follow- stream medicine, or that the research speeds, the prevalence of cervical ing an initial neurotomy, long-term re- has come from only one unit (in Aus- zygapophysial joint pain was found to lief, in excess of 200 days, could be tralia), and has not been replicated by be as high as 88%. achieved in the majority of patients, others. The next phase of research ad- and that relief could be reinstated by Both accusations are false. Inde- dressed the therapeutic utility and pre- repeating the treatment. Moreover, pendent of any of the original investi- dictive validity of cervical medial branch effectiveness was independent of liti- gators, in the latest textbook of pain blocks, i.e., if blocks were positive, did gation, the nature of the electrode medicine (amongst others), they lead to a useful treatment, and did used, and whether patients had been M the use of comparative local anaes- they accurately predict response to diagnosed using comparative blocks thetic blocks is not only endorsed that treatment. or placebo-controlled blocks. but emphasised;26 A randomised, double-blind, placebo Two review papers summarise the M cervical medial branch blocks are controlled trial20 showed that injecting historical background and technical advocated and illustrated;26 painful cervical zygapophysial joints aspects of cervical medial branch M the prevalence of cervical with corticosteroids did not offer any blocks24 and cervical radiofrequency zygapophysial joint pain is recog- greater chance of relief than simply neurotomy25 until about 1998. nised;27 43

44 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks M as is its treatment with terns II: a clinical evaluation. Spine zygapophysial joint pain: a caution. radiofrequency neurotomy.27 1990; 15: 458-61. Neurosurg 1995; 36: 732-39. One study corroborating use of cer- 11. Fukui S, Ohseto K, Shiotani M, et 22. Lord SM, Barnsley L, Wallis BJ, et vical radiofrequency neurotomy has al. Referred pain distribution of the al. Percutaneous radio-frequency neu- been published in abstract form,28 and cervical zygapophyseal joints and cer- rotomy for chronic cervical a prevalence study of cervical vical dorsal rami. Pain 1996; 68: 79- zygapophysial-joint pain. N Engl J zygapophysial joint pain will soon ap- 83. Med 1996; 335: 1721-26. pear in the Medical Journal of Aus- 12. Aprill C, Bogduk N. The prevalence 23. McDonald G, Lord SM, Bogduk N. tralia, and a report of a trial of cervical of cervical zygapophyseal joint pain: a Long-term follow-up of patients treated medial branch neurotomy in the USA first approximation. Spine 1992; 17: with cervical radiofrequency neu- will appear in Spine. 744-47. rotomy for chronic neck pain. 13. Barnsley L, Lord S, Bogduk N. Neurosurg 1999; 45: 61-68. References Comparative local anaesthetic blocks 24. Bogduk N, Lord SM. Cervical 1. Barnsley L, Bogduk N. Medial branch in the diagnosis of cervical zygapophysial joint pain. Neurosurg blocks are specific for the diagnosis of zygapophysial joints pain. Pain 1993; Quart 1998; 8: 107-17. cervical zygapophysial joint pain. Re- 55: 99-106. 25. Lord SM, McDonald GJ, Bogduk N. gional Anesthes 1993; 18: 343-50. 14. Barnsley L, Lord S, Wallis B, Percutaneous radiofrequency neu- 2. Sluijter ME, Koetsveld-Baart CC. Bogduk N. False-positive rates of cer- rotomy of the cervical medial branches: Interruption of pain pathways in the vical zygapophysial joint blocks. Clin J a validated treatment for cervical treatment of the cervical syndrome. Pain 1993; 9: 124-30. zygapophysial joint pain. Neurosurg Anaesthes 1980; 35: 302-307. 15. Lord SM, Barnsley L, Bogduk N. Quart 1998; 8: 288-308. 3. Hildebrandt J, Argyrakis A: Die The utility of comparative local anaes- 26. Buckley FP. Regional Anesthesia perkutane zervikale Facettdenervation thetic blocks versus placebo-control- with Local Anesthetics. In: Loeser JD - ein neues Verfahren zur Behandlung led blocks for the diagnosis of cervical (ed). Bonicas Management of Pain. chronischer Nacken-Kopfschmerzen. zygapophysial joint pain. Clin J Pain 3rd ed. Philadelphia; Lippincott, Man Med 1983; 21: 45-49. 1995; 11: 208-13. Williams & Wilkins, 2001, pp 1893-52. 4. Hildebrandt J, Argyrakis A. Percu- 16. Lord S, Barnsley L, Wallis B, 27. Ghatan S, Goodkin R. Neck Pain. taneous nerve block of the cervical Bogduk N. Third occipital nerve head- In: Loeser JD (ed). Bonicas Manage- facets - a relatively new method in the ache: a prevalence study. J Neurol ment of Pain. 3rd ed. Philadelphia; treatment of chronic headache and Neurosurg Psych 1994; 57: 1187-90. Lippincott, Williams & Wilkins, 2001, neck pain. Pathological-anatomical 17. Barnsley L, Lord SM, Wallis BJ, pp 1003-18. studies and clinical practice. Man Med Bogduk N. The prevalence of chronic 28. Somerville J, Mironer YE. Duration 1986; 2: 48-52. cervical zygapophysial joint pain after of the radiofrequency facet denervation 5. Bogduk N. The clinical anatomy of whiplash. Spine 1995; 20: 20-26. and the outcome of the treatment: the cervical dorsal rami. Spine1982; 18. Lord S, Barnsley L, Wallis BJ, prospective randomized double-blind 7: 319-30. Bogduk N. Chronic cervical study. Presented at the 17th Annual 6. Bogduk N, Marsland A. Third occipi- zygapophysial joint pain after whip- Scientific Meeting of the American tal headache. Cephalalgia 5 lash: a placebo-controlled prevalence Pain Society, San Diego, 5-8 Novem- Supp1985; 3: 310-11. study. Spine 1996; 21: 1737-45. ber, 1998. 7. Bogduk N, Marsland A. On the 19. Gibson T, Bogduk N, Macpherson 29. Speldewinde GC, Bashford GM, concept of third occipital headache. J, McIntosh A. Crash characteristics Davidson IR. Diagnostic cervical JNeurol Neurosurg Psych 1986; 49: of whiplash associated chronic neck zygapophysial joint blocks for chronic 775-80. pain. J Musculoskel Pain 2000; 8: 87- cervical pain. Med J Aust 2001; 174: 8. Bogduk N, Marsland A. The cervical 95. 174-76. zygapophysial joints as a source of 20. Barnsley L, Lord SM, Wallis BJ, 30. Sapir D. Spine (in press) neck pain. Spine 1988; 13: 610-17. Bogduk N. Lack of effect of intraarticular 9. Dwyer A, Aprill C, Bogduk N. Cer- corticosteroids for chronic pain in the vical zygapophyseal joint pain patterns cervical zygapophyseal joints. N Engl Principles I: a study in normal volunteers. Spine J Med 1994; 330: 1047-50. The explicit purpose of cervical me- 1990; 15: 453-57. 21. Lord SM, Barnsley L, Bogduk N. dial branch blocks is to test whether the 10. Aprill C, Dwyer A, Bogduk N. Percutaneous radiofrequency neu- patients pain is relieved by anaesthe- Cervical zygapophyseal joint pain pat- rotomy in the treatment of cervical tising the nerves targeted. 44

45 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks They are not a test of the patients include additional nerves that subtend either normal saline or an active agent, veracity. They test the hypothesis raised those remaining areas. and the third block would need to be the by the treating doctor that perhaps the Cervical medial branch blocks have reciprocal agent. pain is mediated by the nerves speci- diagnostic utility. If positive, they iden- Comparative local anaesthetic blocks fied. tify the source of pain. Establishing a constitute a more practical form of If pain is not relieved, the target positive diagnosis protects the patient control that can be readily incorpo- nerves cannot be regarded as mediat- from the futile pursuit of other and rated into routine and conventional ing the patients pain. A new hypoth- competing diagnosis, and from under- practice. esis about the source of pain is re- going presumptive treatment or treat- A true positive response to compara- quired. The pain may perhaps be ment that is not appropriate for pain tive local anaesthetic blocks is one in mediated by other medial branches, or mediated by the cervical medial which the patient reports complete it may arise from a source not inner- branches. relief of pain for a shorter duration vated by the cervical medial branches. Cervical medial branch blocks have when a short-acting agent is used, and If pain is relieved, the response therapeutic utility, in that a positive for a longer duration when a long- constitutes prima facie evidence that response predicts a good chance of acting agent is used. Such a response the targeted nerves are mediating the obtaining complete relief of pain from is referred to as concordant in that it patients pain; but steps need to be percutaneous radiofrequency neu- is concordant with the expected action taken to ensure that the observed re- rotomy. of the agents used.1 A concordant sponse is not false positive. response confirms that the joint is the It is possible that a patient may have Control Blocks source of pain with a confidence of several sources of pain. For example: Control blocks are essential to ex- 85%.2 M they may have pain bilaterally at a clude false positive responses, and to If a patient obtains complete relief of given segmental level, in which case maximize the confidence of a securing pain but does not report an appropriate anaesthetising the left nerves should a true positive response. The most differential response in terms of dura- relieve the left side of their pain but rigorous form of control is the use of a tion of relief, the joint is not excluded as not the right side (and vice versa); placebo injection of normal saline un- the source of pain. Such paradoxical M they may have pain from more than der double blind conditions, but logistic responses may still be consistent with one segmental level on the one and ethical considerations militate the hypothesis being tested. Indeed, side, in which case anaesthetising against the use of normal saline in some 65% of patients who report such the upper one or two of a series of conventional practice. responses withstand challenge with nerves may relieve only the upper The injection of saline ethically would placebo.2 This paradox seems to arise half of their pain. require informed consent. Impromptu, because, in some patients with chronic single-blind injections of normal saline pain, lignocaine has a long duration of In either instance, complete relief of are unethical. action, ostensibly due to its action on all pain cannot be expected. Indeed, If saline is used it would have to be in open sodium channels. complete relief of all pain is contrary to the context of three blocks of the same What should be the criteria for a what should be expected. Rather, a joint. The first block would have to be positive response to comparative local positive response can be entertained if with an active agent in order to estab- anaesthetic blocks is a matter of judge- there is complete relief of pain in a lish, prima facie, that the joint is symp- ment for the physician. However, the distinct topographical region that con- tomatic. (There is no point in perform- following principles apply. stitutes part of the patients total com- ing routinely a series of three control- If the consequences of a false posi- plaint, but which corresponds to the led blocks in a patient in whom there is tive diagnosis are relatively innocu- area from which pain could be ex- no objective indication that medial ous, less stringent criteria can be used.2 pected to be mediated by the nerves branches are at all mediating the pa- Complete relief of pain on each of two anaesthetised. Although this may con- tients pain.) The second block could occasions, regardless of the duration stitute only partial relief of all of the not be the normal saline control be- of relief, will ensure that all patients with patients pain, it is more accurately cause a mischievous patient would zygapophysial joint pain will be de- and more informatively viewed as com- know that the second injection is al- tected, i.e., ruled in, but the cohort so plete relief of pain in the region ways the dummy and could respond identified will include false-positive targeted. Remaining areas of pain appropriately. In order to maintain the cases.2 This may not matter if irrevers- may be targeted separately, or blocks controlling effect of chance and blind- ible therapies are not being consid- might be extended (within reason) to ing, the second block would have to be ered. But physicians should be aware 45

46 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks that the inclusion of false positive cases and performing blocks can be viewed Patient Selection will undermine the success rate of any as superfluous. The only proposition No studies have been published that treatment. that might be entertained is that medial report empirical data on the validity of If the consequences of a false posi- branch blocks have diagnostic utility clinical criteria that optimize the diag- tive diagnosis are serious, more strin- and, therefore, establishing a positive nostic yield of cervical medial branch gent criteria should be used. In such diagnosis might curtail the futile pursuit blocks, or that might be used to exclude circumstances, the response must be of other diagnoses. That proposition, patients from undergoing blocks. These reliably true positive. The criteria for a however, needs to be weighed care- criteria can be based only on theoreti- concordant response are appropriate fully against the likelihood of obtaining cal considerations, and perhaps on for this purpose.2 negative responses. Proving that pa- advice from those who have contrib- If the consequences of a false posi- tients do not have a condition that they uted to the development of these blocks, tive diagnosis are dire, it would be are unlikely to have is a waste of the based on their experience to date. imperative to perform triple blocks with skills and resources of the investigator. A fundamental criterion is that seri- saline controls in order to be certain Those skills could be better channelled ous possible causes of neck pain, that the response is beyond doubt a into procedures and actions that have such as infection, tumours, vascular true-positive response.2 a greater chance of improving patient disease, and metabolic disease, have What constitutes innocuous, seri- outcome. For this reason, attention been excluded by careful and thor- ous, and dire is a matter of consid- should be paid to careful patient selec- ough history and examination, labora- eration and decision between the phy- tion (see below). tory tests, and medical imaging. The sician, the patient, and any other par- The only validated treatment for pain work-up should provide a diagnosis of ties involved such as an ethics commit- mediated by the cervical medial cervical spinal pain of unknown origin, tee or institutional review board. branches is percutaneous radio- uncomplicated by associated features frequency neurotomy. If this treatment other than perhaps restricted motion. References is not available, the conduct of medial Cervical medial branch blocks are 1. Barnsley L, Lord S, Bogduk N. branch blocks can be justified only on optimally performed in patients with Comparative local anaesthetic blocks the grounds of their diagnostic utility. discrete areas of neck pain that corre- in the diagnosis of cervical zygapoph- However, if radiofrequency neurotomy spond to one or other, or one or more, ysial joints pain. Pain 1993; 55: 99- is available, medial branch blocks are of the areas known from studies in 106. an essential prerequisite before enter- normal volunteers to be associated 2. Lord SM, Barnsley L, Bogduk N. The taining radiofrequency neurotomy. pain produced from a given joint or utility of comparative local anaesthetic Medial branch blocks are not indi- mediated by a given nerve or nerves. blocks versus placebo-controlled cated for acute neck pain. There is a It should be recognised that pain in a blocks for the diagnosis of cervical high chance of acute neck pain recov- certain area does not implicate the zygapophysial joint pain. Clin J Pain ering, despite conservative treatment, zygapophysial joint as the source, nor 1995; 11: 208-13. and radiofrequency neurotomy is not does it implicate the corresponding indicated for acute pain. Therefore, it medial branches. Referred pain maps is not necessary to perform diagnostic only indicate the likely segmental in- Indications blocks in patients with acute neck pain. nervation of the source of pain. That The fundamental indication for cer- In principle, therefore, medial branch source might not be a zygapophysial vical medial branch blocks is the desire blocks are indicated only for patients joint, and could lie outside the territory to know whether the patients pain is with chronic pain. However, it could be of the cervical medial branches. In- mediated by the medial branches of conceded that there is merit in inves- deed, it has been shown that discogenic the cervical dorsal rami. This principle tigating patients with subacute pain, pain refers in patterns almost identical underscores that neck pain, per se, is whose pain is not improving or re- to those of the zygapophysial joints of not an indication for diagnostic blocks. sponding to conservative management. the same segment.1 Not all patients need diagnostic blocks, Although it has not been demonstrated, A critical point is that the recognition so not all patients should undergo blocks. the proposition is attractive that pin- of a pain map does not rely on the total Legitimate reservations can be raised pointing the source of pain in these extent of the pain, which may vary from about the need to perform blocks if the patients and promptly treating it could day to day with the severity of the pain. patient is going to be treated conserva- avert the onset of chronic pain behav- The critical feature for identifying the tively. In that event, the response to iour. area of pain is to determine the centroid blocks does not affect management, of the pain, i.e., where the pain starts, 46

47 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks where it occurs most consistently and References case, medication may need to be with the greatest intensity, and from 1. Grubb SA, Kelly CK. Cervical dis- suspended for an appropriate pe- where it seems to spread to more cography: clinical implications from riod prior to the conduct of blocks. peripheral areas. Metaphorically, the 12 years of experience. Spine 2000; physician should identify the epicenter 25: 1382-89. Neurological signs are a relative of the pain, and use that (not the total 2. Lord S, Barnsley L, Wallis BJ, contraindication for cervical medial extent of the pain) to identify its seg- Bogduk N. Chronic cervical branch blocks, inasmuch as the neu- mental location. zygapophysial joint pain after whip- rological disorder should be managed If the patients pain pattern is unilat- lash: a placebo-controlled prevalence first. If a patient also has neck pain, it eral and corresponds to the pattern of study. Spine 1996; 21: 1737-45. could be investigated with medial a given motion segment, the two medial branch blocks once the neurological branches of that segment should be disorder has been managed or is be- blocked. Contraindications ing managed. Some patients may have neck pain Absolute In that context, radicular pain is not from more than one source. Their The absolute indications for cervical a contraindication for medial branch overall distribution of pain will be a medial branch blocks are conditions in blocks, but the investigator should not composite of more than one segmental which the conduct of a needle proce- be under any misapprehension that pattern. The most common combina- dure under x-ray control might jeop- medial branch blocks will relieve radicu- tions are bilateral pain at the same ardize the patients health. These in- lar pain. Medial branch blocks are segmental level, pain from consecutive clude, but are not necessarily limited to indicated if the diagnostic hypothesis motion segments (most often C5-6 and the following: is that the patients neck pain and any C6-7), or pain from displaced sites M bacterial infection, systemic or lo- somatic referred pain might be medi- (most often upper neck pain and head- calized in the region of the blocks to ated by cervical medial branches, but ache from C2-3 and neck-shoulder be performed; is a concomitant but separate problem pain from C5-6).2 For these patients M bleeding diathesis, due to to their radicular pain. certain precautions should be taken to haematological disease or antico- avoid inaccurate, inefficient, and ex- agulants; cessive investigation. These steps are M possible pregnancy. Facilities Required outline later under Interpretation and Radiological Equipment under Algorithm. Relative Fluoroscopy is mandatory for the As yet unpublished data indicate that Relative contraindications are con- conduct of cervical medial branch patients whose pain does not corre- ditions that do not preclude the con- blocks. The preferred equipment is a spond to a single motion segment, or duct of cervical medial branch blocks C-arm fluoroscope that allows the x- whose distribution of pain defies re- but which require special considera- ray beam to be directed at any angle. duction sensibly into a composite of tion because of the risks they pose. In Furthermore, in order to document the discrete segmental patterns, are very the face of these conditions the inves- accurate placement of needles and the unlikely to respond to medial branch tigator may elect not to perform medial spread of contrast medium a device blocks. Such patients have very wide- branch blocks, or if they do undertake must be available to obtain either hard- spread pain and extensive tenderness, blocks special precautions are required. copy films or an image on specialised and cannot identify centroids for their These conditions include, but are not paper. pain. In such patients, medial branch necessarily limited to the following: blocks cannot be proscribed until valid M allergy to contrast media, which Resuscitation Equipment data are published, but lest it give the may require cover with corticoster- Although misadventure attributable use of medial branch blocks a bad oid and H1 and H2 antagonists; to the agents injected is extremely reputation, it is probably unwise to M allergy to local anaesthetics, which unlikely, given the small doses injected squander medial branch blocks in these may require identification and use for cervical medial branch blocks, it is patients. The diagnosis is unlikely to be of a class of anaesthetic to which probably wise to perform the proce- zygapophysial joint pain, or the sources the patient is not allergic; dure in a facility equipped with proper of pain will be so extensive as to defy M concurrent treatment with non- resuscitation facilities. At the very least, responsible treatment with radio- steroidal anti-inflammatory medi- the operator is thereby equipped to frequency neurotomy. cations, including aspirin, that may deal with possible allergic reactions to compromise coagulation, in which 47

48 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks local anaesthetic agents. A history and physical examination are required to exclude pain likely not Needles, Gowns, Drapes, etc. to be of zygapophysial joint origin and A 90 mm, 25 gauge needle is optimal, to identify or exclude contraindications for it is minimally painful when passed to blocks. Pain maps are used to select through the skin and muscles overlying which should be the target nerves in the the target joint. first instance (Fig. 1). Otherwise, a The needle may or may not have a history and physical examination are Luer lock, but such a lock is preferable. required to record baseline data con- A standard preparation tray may be cerning the location and extent of pain, used, which comes with cotton balls including a visual analogue score, and and gauze, but more elaborate trays the movements and activities of daily can be custom made to come with living that are customarily prevented needles and local anaesthetic. by the pain. Figure 1. Map of referred pain from the cervical zygapophysial joints. Solutions for skin preparation may On obtaining this baseline history, be an iodine-based solution (e.g., the patient should be briefed as to how Povidone-iodine), chlorhexidine, or their response to blocks will be meas- and alcohol-based antiseptic (e.g., ured. They should be instructed in the Premedication chlorhexidine 0.5% in 70% alcohol). use of any pain diaries or visual ana- No premedication is required. Sterile gloves are used. logue scales that might be used. Local anaesthetic agents may be injected directly from a syringe at- Informed Consent Technique tached to the spinal needle, or minimal Informed consent must be obtained. Preparation volume extension tubing may be inter- Although medial branch blocks should Neither physiological monitoring nor posed between needle and syringe, be safe procedures, like any invasive intravenous access is required. according to operator preference. procedure they carry the nominal risk Given that only a small volume of of infection, bleeding and allergic re- Positioning agent is injected, a 2 ml syringe is all action. After upper cervical blocks the Although a posterior approach is that is required. patient is likely to suffer temporarily a possible, the most convenient and tech- sense of ataxia. These risks should be nically least demanding approach for Medications explained to the patient who should be cervical medial branch blocks is a Intravenous solutions, sedation or advised of the precautions to be taken. lateral approach. For this the patient antibiotics are not required. The patient should be advised that lies on their side with the painful side the procedure is a diagnostic one, and uppermost. A device to hug, such as a Agents should not be confused with a thera- pillow or a teddy-bear, serves to ac- Any conventional local anaesthetic peutic procedure. They should be commodate their arms, if required. can be used for medial branch blocks. advised that they may or may not Agents most commonly used are obtain relief, and that in particular they Sterility bupivacaine 0.5% and lignocaine 2%. should be prepared for no relief ensu- The skin of the lateral neck must be Other concentrations that can be used ing. They should be advised that ex- exposed, and the patients hair should are bupivacaine 0.75% and 0.25%, pecting any particular result confounds be prevented from falling into the field and lignocaine 1% and 4%. Because the purpose of the test, and that they of the procedure. Patients with long of the small volumes used, high con- should report the result honestly. hair could wear a surgical cap. centrations should generally be used Other than to expect either relief or Once the patient is in position the in order to obtain the most effective no relief, the patient should not be proposed entry point and surrounding anaesthetic effect. For medial branch informed of the duration of relief to area must be adequately prepared as blocks, no more than 0.3 ml is required expect. They should be prepared only for an aseptic procedure, using one of to block the nerve adequately. to the effect that if relief ensues they will the solutions listed above. The pre- need to monitor and record its duration pared area must be allowed to dry in and extent. order to ensure sterility. A fenestrated Preliminary Procedures drape made of cloth, paper, or plastic History and Physical Examination should be applied to cover the non- 48

49 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks sterile areas surrounding the prepared superior articular process, the target quickly through the skin, and carefully area. point for a C7 medial branch block will lie through the neck muscles but only to a substantially above this silhouette. depth sufficient to obtain purchase for Target Identification the needle, to stop it swaying if re- As near as perfect, a true lateral view 3. For third occipital nerve blocks leased. Its position and orientation of the cervical spine must be obtained. Three target points are used in order should then be checked to ensure that In such a view, the silhouettes of the to ensure adequate infiltration of the it overlies and is pointing towards the articular pillars of both sides at a given third occipital nerve, which is thicker target point within a tolerable error segment are superimposed. Tilting the than the medial branches of typical zone. If this is not the case, the needle x-ray beam slightly, around the long cervical dorsal rami, and which is should be reinserted at a point at which axis of the patient, should split the embedded in the pericapsular fascia it does satisfy these criteria. images of the superimposed silhou- of the C2-3 joint, and which has a ettes, which confirms superimposi- variable location in relation to this joint. For medial branch blocks at C3-C6. tion. This confirmatory step is essen- The target points lie on a vertical line The tolerable error zone for insertion tial, for failure to obtain a confirmed, that bisects the C2-3 joint. The high and passage of the needle should be true lateral view risks aiming a needle target point lies opposite the level of the no greater than the middle half of the towards the contralateral side of the apex of the C3 superior articular proc- area of the articular pillar across which neck. esses. The low target point lies oppo- the target nerve runs. When the needle The fluoroscope should be aligned site the bottom of the C2-3 interverte- is inserted, its tip should not stray so that the target point is at the center bral foramen. The middle point lies outside this zone. This standard en- of the x-ray beam, i.e., so that it ap- midway between these foregoing points, sures that needles are not directed too pears on center-screen. This avoids usually on the subchondral plate of the obliquely so as to require multiple in- any errors due to parallax. superior articular process of C3. sertions, withdrawals, and over- corrections. The needle is progres- 1. For medial branch blocks C3-C6 Needle Placement sively inserted towards the target point, The target point is the centroid of the A puncture point on the skin is se- using periodic screening to check its articular pillar with the same segmental lected overlying the target point, check- course, and undertaking any correc- number as the target nerve. This ing that a subcutaneous vein is not tions required to its course. As the centroid is found at the intersection of about to be penetrated. If a vein lies in needle passes progressively more the two diagonals of the diamond- the intended path of the needle, the deeply, its tip should appear to overlie shaped pillar. puncture point is relocated slightly so the target point progressively more as to avoid venipuncture. Also, in order closely. In effect, coarse corrections 2. For medial branch blocks C7 to minimise discomfort during the pas- to the path of the needle should be The target point lies high on the apex sage of the needle, particular at upper undertaken only while the needle is of the superior articular process of C7. cervical levels, it is preferable to avoid relatively superficial, and only fine This is because the base of the C7 piercing the sternocleidomastoid mus- corrections should be required as its transverse process occupies most of cle, if possible. If the puncture point tip nears the depth of the target point. the lateral aspect of the C7 articular initially selected overlies the sterno- Once the needle rests on the target pillar and thrusts the medial branch cleidomastoid, the patient can be asked point 0.3 ml of local anaesthetic can be relatively higher than typical cervical to rotate their head slightly, into the injected in order to anaesthetise the medial branches. The presence of this pillow, in an effort to draw the muscle target nerve. In order to anaesthetise transverse process should be real- forwards, so that it no longer lies under a typical cervical zygapophysial joint ised, for it is not readily apparent on the puncture point. both the medial branches that inner- lateral views, but it may confound ac- Prior to penetrating the skin, the tip vate the joint should be anaesthetised. curate needle placement. If too low a of the needle should be placed on the target point is selected, the needle may intended puncture point, and the shaft For medial branch blocks at C7. The strike bone and appear to rest on the aligned parallel to the x-ray beam. This tolerable zone for insertion and pas- superior articular process but it will allows the needle to be directed straight sage of the needle should be no greater instead be resting on the transverse towards the target point without having than triangular silhouette of the supe- process which points, end-on, towards to judge the magnitude of angles, which rior articular process of C7. When the the operator. If the silhouette of its base is required if an oblique insertion is needle is inserted, its tip should not can be perceived superimposed on the used. The needle is then inserted stray outside this zone. This standard 49

50 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks ensures that the needle does not pass line approximately through the poste- If the patient complains of any unto- deeper than the depth of the superior rior edge of the inferior articular proc- ward side effects following the proce- articular process, into the C8 interver- ess of C2. When the needle is in- dure, appropriate action must be taken. tebral foramen, or through the C6-7 serted, its tip should not stray outside Vaso-vagal episodes may occur. These zygapophysial joint. The needle is in- this zone. This standard ensures that are managed with pulse and blood serted carefully and slowly, with fre- the needle does not pass into the C2- pressure observations and rest in the quent screening to check progress, 3 intervertebral foramen, or too far supine position. Rarely is any further such that the tip never strays beyond away form the target points. intervention indicated. the tolerable error zone. If at any time The needle is inserted carefully to- Patients who undergo upper cervical the needle tip strays beyond this zone, wards the middle of the three target procedures, particularly third occipital it should be withdrawn sufficiently to points, using periodic screening to nerve blocks, are very likely to report allow it to be reorientated so that tip lies check its course. If at any time, the a sense of ataxia. This occurs because within the error zone. Once the needle needle strays out of the error zone, it the blocks anaesthetise upper cervical appears to have contacted the supe- should be withdrawn sufficiently to proprioceptors which are critical for rior articular process, a postero-ante- reorientate it so that it points towards tonic neck reflexes. To compensate rior view should be obtained to confirm the target point. The needle is progres- for this they should be instructed to that the needle tip lies right against the sively inserted until it rests on the low engage and rely on visual cues. This is lateral margin of the superior articular target point. Once the needle is in achieved by having the patient always process. If instead, it transpires that position and rests on bone, it should be focus on objects horizontal, regard- the tip has struck the upper surface of withdrawn slightly, by a length equal less of whatever they do. Such objects a thick C7 transverse process and lies approximately to the thickness of the include window frames, door frames short of the superior articular process, capsule of the joint. This step ensures or the horizon itself. They should be the needle should be readjusted under that the needle has not penetrated the warned that if they look downwards or lateral views to a higher location on the joint capsule, and that an injection will if they look sideways to a companion superior articular process, and its not be intra-articular instead of they will incur the sense of unsteadi- position checked and confirmed once perineural. Once the needle has been ness and so must avoid these actions. again on PA view. withdrawn, 0.3 ml of local anaesthetic They can be reassured that if they Once the needle is in correct posi- can be injected. follow these precautions they should tion, 0.3 ml of local anaesthetic can be The needle is then readjusted to not meet with misadventure. Further- injected in an attempt to infiltrate the either the upper or lower target point, more, they are very likely to adjust to target nerve. Once that is done, how- at which 0.3 ml of local anaesthetic can the strange sensation within 15-30 ever, the needle should be withdrawn be injected. minutes. They should be reassured about 4 mm and a further aliquot of 0.3 The needle is finally readjusted onto that the sensation will be only tempo- should be injected. The step caters for the remaining target point where 0.3 ml rary. the variation in which the C7 medial of local anaesthetic can be injected. Because of the giddiness, patients branch, instead of running across the must be advised not to drive a motor surface of the articular process, is Records vehicle, because sudden loss of con- displaced away from bone by a bundle An image demonstrating the needle tact with the horizon, such as upon of the semispinalis capitis. If required, position must be obtained whenever a sudden turning of the head, may result postero-anterior screening can be used substance is injected. A plain radio- in temporary loss of control of the to gauge the depth of withdrawal of the graph may be obtained using conven- vehicle. needle. tional film or specialised paper. Such Otherwise the procedure is usually a record protects the operator in the well tolerated, and the patient may be For third occipital nerve blocks. The event of alleged misadventure. allowed to dress and await evaluation tolerable error zone is a rectangular and discharge. area bounded by the anterior edge of Discharge instructions include: the superior articular process of C3, Post-procedural Care M to contact the doctor who performed upper and lower lines perpendicular to Upon removal of the needle, the skin the procedure if there is any unu- this edge passing posteriorly from the is cleaned to remove the antiseptic and sual symptom or pain following the apex of the superior articular process any blood. A small adhesive patch can procedure. Fever and tenderness and from the bottom of the C2-3 in- be applied to the puncture sites, but is greater than that which might be tervertebral foramen, and a posterior probably unnecessary. ascribed to a needle track may be 50

51 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks signs of infection. To this end, an and report as positive a block whose successful. This can occur when a instruction sheet with a name and effect has not truly been positive, or patient has multiple sources of pain. telephone number is useful. This report as completely effective a Although a block may successfully sheet should be separate to any block that has been only partially anaesthetise one of their sources other data sheets given to the pa- effective. of pain it may not relieve other tient. M Blocks may be performed at a time sources. Consequently, when M to monitor the extent and duration of when the patients pain is minimal, asked, in absentia, if their pain was any relief that ensues. To this end or even absent. In that event it is relieved the patient, having not ob- a pain diary is helpful. However, difficult to argue that any supposed tained total relief of all of their pain, critical is the time when the pain relief obtained was due to the ef- may report that it wasnt. starts to return and the time that it fects of the block, and not simply a returns to its former, accustomed reflection of the patients low level of Such errors have potential ramifica- intensity. pain at the time. tions with respect to both medicolegal M if relief occurs, the patient should M If the response to a block is evalu- proceedings and treatment. Blocks carefully attempt the movements ated immediately and only upon subject to error may lead to false and activities of daily living that completion of the block, a false conclusions about the veracity of a customarily are restricted by pain, impression may arise. Having rested source of pain. Liability, therefore, in order to determine whether these during the performance of the block may subsequently be misattributed. A movements and activities can be the patient may obtain relief of the false conclusion may lead to inappro- resumed while pain free. They pain. If asked if there is any relief priate therapy that is destined to fail. It should record those movements upon completion of the block the is therefore, imperative that informa- and activities that they have been patient will correctly respond that tion based on diagnostic blocks be able to resume. there has been relief, but when reliable and valid, i.e., free from error. subsequently they resume activi- Certain errors can be reduced by Evaluation ties of daily living it may become performing diagnostic blocks under The singular reason for performing apparent that the block has, in fact, double-blind conditions. When the diagnostic blocks is to obtain infor- not produced a positive effect. patient does not know which agent is mation. That information depends on M If a patient is discharged following being used, they cannot conform to an a reliable evaluation of the patients completion of a block and their expected response. Simultaneously, response to blocks. Although perform- response is assessed at some time the double-blind paradigm prevents ing the diagnostic block is an essential later, be that by telephone interview the doctor, or an independent asses- first step, the block itself does not make or at a subsequent consultation, sor, from coaching the patient as to the diagnosis. Unless the patients re- they may suffer recall bias. They what response to expect. Unless a sponse is carefully evaluated and con- may not remember accurately how diagnostic block is performed under trolled for false-positive responses, much relief they obtained and for double-blind conditions, the risks of performing the block is a waste. how long. Furthermore, their report response bias, observer bias, and re- There are several potential sources is entirely subjective, no independ- porting bias, remain eminent, regard- of error in the assessment of a re- ent trained observer having cor- less of how honest and objective a sponse to a diagnostic block. roborated objectively the validity of doctor claims, or insists, they are. The their response. elimination of other sources of error M Patients who expect and want a M Although patients in absentia might require other measures, as outlined block to work may suffer a placebo be asked to complete a graphic below. response, and obtain or report re- record of their pain levels, this proc- lief for reasons other than the phar- ess is confounded by the patient Towards An Optimal Protocol macological effects of the block. having access to what they previ- At a Master Class conducted by the M A doctor who expects or wants the ously recorded. Guidelines for the International Spinal Injection Society block to work may overtly or sub- completion of serial visual analogue at the University of Newcastle in 1998, consciously coach the patient to scales for pain maintain that pa- participants discussed the issues raised report a positive effect even when tients should not see their previous above. They agreed that the signifi- one is not truly achieved. entries.1 cance of diagnostic blocks for spinal M An assessor who wants the block to M An untutored patient may fail to pain lay in the information obtained, work may exercise observer bias, recognise that a block has been not in the execution of the block. They 51

52 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks recognised the potential sources of completed, and that the patient has no concerning the response. The narra- error when blocks were not performed resulting side effects that require im- tive serves to corroborate the response under controlled conditions. mediate medical attention, they return inferred from the visual analogue The meeting resolved that the optimal the patient to the RN for assessment scores for pain. When a patient scores means of reducing error and securing and evaluation. The doctor takes no zero on the VAS but is not pleased by reliable diagnostic information was part in this evaluation, and is free to the effects of the block, doubts can be real-time assessment. Under this continue with other patients. raised about the effectiveness of the protocol, the response to a diagnostic The assessor evaluates the patients block. Conversely, the assessor can block is evaluated immediately after response to the block, administering be more confident in the response if the block and for some time afterwards the instruments that have been se- the patient reports feeling the best that at the clinic at which the block was lected for this purpose. (See Schedule they have felt in years, or other such performed, and by an independent A, below.) descriptions. Reciprocally, a patient observer using validated and objective The assessment continues in princi- who verbally reports that they obtained instruments or tools. ple for the duration of the patients complete relief but fails to indicate that Under the protocol, the doctor who is response to the block, or until the on their visual analogue scale should to perform the diagnostic block intro- effects of the block have been reason- explain the discrepancy. duces the patient to an independent ably established beyond doubt. Once the assessor has completed observer, typically a registered nurse the assessment it should be reported to The doctor describes the pain that is M If the patients pain has not been the doctor who should review it. The being targeted by the forthcoming relieved, the patient can be pre- doctors responsibility in this regard is block, and if appropriate, highlights pared for discharge once it has to ensure that the assessment has how this pain is distinguished from any been clearly established that there been properly conducted and thor- other pain that the patient might con- has been no relief. oughly recorded. The doctor cannot currently have. M If the patient reports relief, this dispute the assessment. They can, Both the doctor and the assessor should be monitored and corrobo- however, identify whether there has should determine and agree that the rated by the assessor for at least been any misinterpretation, for exam- patients level of pain is sufficiently two hours or until the effects of the ple if the patient and the assessor both intense for any response to the in- local anaesthetic agent wear off, misconstrued which of a patients sev- tended diagnostic block to be credible whichever is the sooner. If possible eral pains was targeted by the block and meaningful. logistically, the relief should be moni- undertaken. Any corrections to the In this regard, a reasonable guide- tored for longer. In this regard, the record in this regard should be de- line is that the patients present pain period of two hours is nominated as scribed in narrative. In order to avoid should be no less than 50% of their a minimal period that seems prac- ambiguity, misinterpretation, or mis- pain at its worst. Serious consideration ticable in general. Patients who representation, the original assess- should be given to the propriety of need to travel, or who need to return ment form should not be amended; proceeding with blocks either in pa- to work or to other duties may find instead, a revised assessment form tients whose typical pain is less than 40 it inconvenient to remain for a longer should be appended to the original on a 100 mm scale, or in patients period. form, along with an explanation of why whose pain at the time when the block and how the revision was undertaken. is to be undertaken is less than or equal The patients response should be Once the doctor has reviewed the to 20 on a 100 mm scale, for the natural recorded independently by the asses- assessment, the patient can be dis- diurnal variation in pain may be of this sor at prescribed periods. A reason- charged. magnitude; and a decrease in pain by able schedule is to record the level of Subsequently, the assessor should only 20 points may not be legitimately pain before the block, immediately review the patient in order to determine ascribable to the intervention. after the block, 30 minutes after the and record the patients longer-term Separately with the patient, the as- block, and hourly thereafter. The as- response to the block. This could be sessor records baseline measures sessment of pain should be comple- done by telephone interview on the pertaining to the patients pain. mented by an assessment of any im- following day. This review should record Separate from the assessor, the provement of disabilities, and by a the ultimate duration of any positive doctor performs the diagnostic block. narrative description of either how the effect of the block, in terms of when the Once the doctor is satisfied that the patient feels about the relief obtained, patients pain returned, how they felt block has been adequately and safely or any difficulties that they may have during the period of relief, and any side 52

53 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks effects or reservations about the ef- the block, and repeatedly through- that side will be relieved but the pain fect. The use of telephone enquiry out the period of assessment, these of the other side will not be relieved. does not offend the reservation out- disabilities should be assessed and M in a patient with pain mediated by lined above about recall bias, because the degree of restoration recorded. three consecutive nerves, if only the patients primary response has the upper two are blocked, the already been recorded. The telephone 3. To corroborate the assessors patient may obtain relief of the enquiry simply obtains supplementary record of the assessment, a power- upper part of their pain, but no relief information concerning the patients ful tool is to videotape the patient of the lower part. The converse subsequent course and welfare. executing activities before and af- applies if the lower nerves are ter the block. Such a record could blocked. Reference also include the patients mood and 1. Carlsson AM. Assessment of chronic facial expression. Such responses nevertheless con- pain. I. Aspects of the reliability and stitute a positive response, for the pain validity of the visual analogue scale. Appendix A, shows an example of a targeted by the blocks was completely Pain 1983; 16: 87-101. form that succinctly records an as- relieved. The responses may be partial sessment. topographically but they are complete physiologically, in the targeted area. Schedule A. Instru- Interpretation In the event of such responses, a comprehensive or systematic ap- ments for Assessing A positive response to a block is, prima facie, one in which there is proach may be undertaken for a com- plete and accurate diagnosis. Response complete of relief of that part of the patients pain which the blocks might If the patients pain is bilateral and corresponds to the pattern for a par- A variety of instruments might be be expected to relieve, for a duration ticular segmental level, used to assess the effects of a diag- commensurate with the expected du- M the two nerves on each side of the nostic block. There is a risk, however, ration of action of the local anaesthetic same segment may be blocked, or of overloading a patient with enquiries, used. Partial reduction of that pain M the patient could be assessed as if questionnaires, and other tools. A prag- does not constitute a positive response. they have two pain sources, one on matic approach is to use three instru- The only exception can be that the each side, and each side is ad- ments. patients accustomed pain is com- dressed systematically but inde- pletely relieved but they complain of pendently. 1. Relief of pain can be recorded by pain from the needle track, which would using serial visual analogue scales. not be relieved by a medial branch If controlled blocks on each side block. relieve the pain on their respective 2. Relief of disabilities can be re- If the patients pain is mediated by sides, a subsequent block may be corded by having the patient nomi- the nerve or nerves anaesthetised, undertaken simultaneously bilaterally, nate four, or as many as possible, they should obtain complete relief of if it is necessary to show that all of the activities of daily living that (1) are their pain. patients pain can be relieved at the impeded or prevented by their pain; If the patients pain is mediated by one time. (2) which are likely to be restored, nerves other than the ones anaesthe- If blocking one side relieves all of the or should be restored, if the pain is tised, they should obtain no relief of patients pain bilaterally, there is no relieved; (3) and which can practi- their pain. need to proceed with investigation of cally be assessed in a clinic setting. If the patients pain is mediated by the opposite side. (Examples might include bending, several nerves, including but more The latter approach is intellectually lifting, turning, sitting, walking. Im- than the ones anaesthetised, the pa- more efficient and less subject to di- practical examples include return tient will obtain relief of that part of their agnostic noise, for it allows the dem- to work, sleeping, and having sex.) pain that is mediated by the nerves onstration of bilateral pain stemming To this end, the assessor should anaesthetised, but no relief of pain from just one side, if that is the case. record the nominated activities mediated by the other nerves. Exam- However, in some settings it might not before the execution of the block, ples include: be practical or convenient for the pa- and observe and note the demon- M in a patient with bilateral pain, if only tient to return for systematic investiga- strated degree of disability. After the left side is blocked, the pain on tion; in which case it might be prefer- 53

54 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks Appendix A. Example of Form Suitable for Real-Time Assessment 54

55 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks able to block both sides of an appar- Investigating both sources separately and foremost to determine whether ently unisegmental pain simultaneously; also allows cases to be identified in headache or neck pain is the patients or, once a single block on each side which upper cervical as well as lower dominant symptom. This question does has been found to relieve the pain on cervical pain arise from only an upper not disqualify a patient from eventually the respective side, a confirmatory cervical joint, or in which lower cervical being investigated both for their head- block may be undertaken simultane- as well as upper cervical pain arise ache and for their neck pain. Indeed, ously on both sides. from a lower cervical joint. Such cases the algorithm allows for a patient with If the diagnostic hypothesis is that will not be identified if it is presumed headache to return for investigation of the patients pain is mediated by mul- that the two sites of pain have separate their neck pain in the event that inves- tiple, consecutive medial branches, sources. Using such a presumption to tigations of their headache should prove and if they obtain relief of the upper half proceed summarily with blocks at up- negative. of their pain when the upper nerves are per and lower levels simultaneously The purpose of the initial question Is blocked, it should transpire that block- may result in more nerves being in- headache dominant is to direct inves- ing the lower nerves will relieve the criminated than warranted. tigations to appropriate levels in the lower half, but not the upper half, of For patients with multiple and bilat- cervical spine. The available epide- their pain; and all of their pain should eral sources of pain mediated by the miologic data indicate that cervicogenic be relieved when all nerves responsi- cervical medial branches, it may not be headache most often stems from the ble are blocked. Although it takes one possible to anaesthetise all sites simul- C2-3 and adjacent joints.1 Only rarely more procedural session than it does taneously. If a comprehensive diagno- does it arise from C4-5, and it has not to diagnose a unisegmental pain, it is sis is required, each site might have to been proven to arise from joints lower preferable to diagnose multilevel pain be confirmed separately, or in combi- in the neck.2 In a patient with headache as a staged procedure. The first block nations that are both sensible and greater than neck pain, it becomes relieves the upper region of the pa- practical. more likely that a positive diagnosis will tients pain; a second block relieves the be established by starting investiga- complementary region of pain; and the Performance Parameters tions at C2-3. To start at other levels third, confirmatory, control block can Although experienced and expert defies the pre-test probabilities, and address all levels at once. A staged operators may be more efficient and renders the diagnostic process ineffi- procedure in this manner, secures a faster than the following standards re- cient. valid diagnosis. It avoids wrongly pre- quire, the parameters that define a If a diagnosis is not established by suming, ab initio, that the pain is me- minimum level of competence and pro- pursuing the headache, the algorithm diated by multiple, consecutive nerves, ficiency for the performance of cervi- allows for a return to pursue the neck and blocking all of those nerves. Doing cal medial branch blocks are: pain. However, it poses two questions: so may lead to false positive results M not more than eight adjustments or whether the neck is nonetheless a when more nerves are incriminated corrections of the course of the problem, and whether the neck pain is than warranted. needle from insertion to reaching worth pursuing with blocks. These A third circumstance is where the the target point; questions rely upon the practitioners patient has two, displaced sources of M not more than six adjustments to discretion and intuition, because there pain, e.g., upper cervical pain and move from one target point to an- are no objective data by which these headache stemming from C2-3, and other in the conduct of a third questions might be answered. lower cervical pain and shoulder pain occipital nerve block; In this regard, the algorithm is poten- stemming from C5-6. In those circum- M not greater than 1.5 minutes total tially educational. Practitioners can stances, blocking the third occipital radiation exposure time to block a audit their experience and determine nerve will relieve the headache but not given nerve, which includes expo- whether positive responses to these the neck-shoulder pain; and con- sure time to identify the target point questions prove profitable in their ex- versely, blocking C5,6 will relief the and puncture point, prior to inser- perience. If they are not, the practi- neck-shoulder pain but not the head- tion of the needle. tioner should reflect on the validity of ache. In such cases, the two compo- the criteria that they have been using nents of the patients complaint should be addressed separately, blocking one An Algorithm to establish affirmative responses to the questions, and correct those crite- at a time. By this measure, it can be Part 1: Initial Assessment ria in the interests of improving the shown beyond doubt that the two sites The first part of the algorithm is an efficiency of their practice. of pain have independent sources. overview. It invites practitioners first 55

56 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks Algorithm Part 1: Initial Assessment Part 2: Headache Algorithm proceeding with blocks is justified and blocks. When practitioners encounter The algorithm commences with a likely to yield results. For a patient who one or more technical failures, the surprising question, are confirmatory has not commenced blocks the implicit question invites them seriously to con- blocks positive? The virtue of this answer is obviously yes, which per- sider why they should persevere. idiosyncrasy is revealed later, once mits entry further into the algorithm. The definitive section of the algo- the algorithm operates. In essence, it Later, in the face of negative results, rithm asks whether the C2-3 joint has is an invitation to stop. In the first the answer to this question may be been excluded. This joint is specified instance, the logical answer to this no. In that event, the algorithm invites as the starting point because the epi- question for a patient who has not yet cessation of investigations. This ques- demiologic evidence indicates that, of commenced investigation is no. That tion is not based on absolute criteria. patients with neck pain in whom head- answer permits entry deeper into the Rather, it offers the practitioner the ache is the dominant feature, the algorithm. opportunity to decide that enough is chances of C2-3 being the source are The next question constitutes a node enough. It is placed in the algorithm 54%.1 Most patients, therefore, will of accountability. It asks the practi- largely to accommodate negative re- have pain stemming from this level. tioner intuitively to answer whether sponses and technical failures of Investigating patients for this condition 56

57 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks Algorithm Part 2: Headache 57

58 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks is the most efficient step. There is no are not performing the procedure cor- for medial branch blocks of typical evidence to support beliefs that a prac- rectly. cervical zygapophysial joints(see titioner can tell whether a patient has If the response to the confirmatory Technique above). headache stemming from a different block is positive, a diagnosis of C2-3 Blocks of the C3,4 medial branches level. Therefore, starting at any other joint pain is established, and investiga- should not be subject to technical fail- level is not justified. tions cease. This should be the most ures. Accordingly the questions con- The established test for C2-3 joint common outcome of the algorithm. It is cerning technical adequacy should be pain is a third occipital nerve block.1 reached within two blocks, but perhaps ignored when evaluating the response This should be performed in the man- three, if there has been a technical to these blocks. ner described above (see Technique). failure. Some 50% of patients, there- If C3,4 blocks prove positive the A real and genuine problem that fore, should be subjected to no more diagnosis is established. On the aver- does occur with the conduct of third than three procedures, and most of age, patients with headaches stem- occipital nerve blocks is the failure to these to only two procedures. ming from C3-4 would be diagnosed anaesthetise the target nerve ad- If the response to C2-3 blocks is within three procedures: the first being equately. This may occur in up to one- negative, the algorithm calls for reflec- a third occipital nerve block whose third of cases. It is, however, immedi- tion. result is negative and which excludes ately evident. The patient fails to obtain If the first block of C2-3 is positive but C2-3, a second to establish prima anaesthesia in the cutaneous territory the confirmatory block is negative, a facie a positive response to C3,4 innervated by the nerve. This event conundrum arises. This is a paradoxi- blocks, and a third to confirm the invites repetition of the block, either on cal response. Either the first block was response. a subsequent occasion, or as soon as false positive or the confirmatory block If the results of the confirmatory practicable on the day of the first was false negative. Without further block are negative, investigations procedure once the failure is recog- and multiple investigations these pos- should cease, for the same reasons nised. For this reason, the algorithm sibilities cannot be distinguished. The outlined above in the context of nega- asks whether there has been a techni- answer does not lie in simply repeating tive response to confirmatory blocks of cal failure. If not, the patient proceeds the block until another positive re- C2-3. deeper into the algorithm. But if the sponse is produced. This constitutes If C3,4 blocks are negative, the C1- block has been technically inadequate, illusory logic. Obtaining further posi- 2 joint should be considered. However, the practitioner is asked to consider tive response does not wipe out the a major caveat applies. C1-2 blocks whether persevering with a repeat block negative response, and may itself be are not easy to perform, and carry is justified. In most cases the response another false positive response. It might risks greater than other cervical joint would be yes, but in some instances be argued that a patient could undergo blocks. Consequently, the algorithm it might be that the practitioner two or three repetitions in order to asks whether C1-2 blocks can be safely recognizses irregularities, such as establish by averaging that the one and done. If the answer is yes, the algo- osteophytes in the target region, that only negative response was false nega- rithm invites performance of the ap- render it unlikely that repeating the tive, but doing so invokes the possibility propriate block. block will avoid another technical fail- of coaching the patient into having a C1-2 blocks require an intra-articu- ure. positive response. In the absence of lar injection, for which safe techniques If the result of the first block of the C2- an efficient means of resolving the have been described.3-5 The questions 3 joint is positive, the algorithm re- conundrum, the algorithm recommends of technical adequacy do not apply quires a confirmatory block. that no further investigations be pur- when these blocks are performed. Furthermore, the algorithm allows sued. The course of two or more fur- If C1-2 blocks are positive and con- for a possible technical failure and ther investigations, simply to resolve firmed, a diagnosis is established. repetition of the confirmatory block. the conundrum under dubious condi- According to the algorithm, this is This step essentially presumes that tions denies new patients access to the achieved within four steps: one block there have been no previous technical resources of the practitioner. each to exclude C2-3, and C3-4, one failures. However, practitioners should If the first block of C2-3 is negative, to establish prima facie that C1-2 is consider seriously whether they en- the investigation can proceed to other positive, and one to confirm the re- counter technical failures more than segmental levels. sponse. once in a given patient, or whether The algorithm invites consideration If the response to C1-2 blocks is technical failures are inordinately com- next of the C3-4 joint. This joint should negative, or if C1-2 blocks cannot be mon in their practice. Perhaps they be blocked using standard techniques safely performed, the algorithm asks 58

59 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks whether atlanto-occipital blocks (O- pain attributable to a zygapophysial would constitute extenuating circum- C1) can be performed safely. If not, all joint, investigations should not be un- stances, and is not covered by this investigations cease, and the diagno- dertaken, for the probability is low of algorithm. sis is indeterminate. If O-C1 blocks are determining a confident diagnosis in If all joints have been excluded, fur- available, they can be performed as patients whose pain is not so distrib- ther investigations are unlikely to yield the final possible step in the investiga- uted. In particular, the yield of positive a positive result, and investigations tion of headache. zygapophysial joint blocks is essen- should cease. The prevalence of O-C1 headaches tially nil in patients with widespread If all joints have not been excluded, is not known, but is presumably low. pain with no focal epicenter. but previously selected joints have been For that reason it is the last joint to be If a pattern is identified according to excluded, the next most likely joint entertained by the algorithm. If it is the the pain maps for zygapophysial joint should be selected and investigated. responsible joint, the algorithm finds it pain6 the corresponding segment Whether the joint is the first to have positive within five steps: one each to should become the target for investiga- been selected, or is a joint subse- exclude C2-3, C34, and C1-2, one to tions. quently selected, the first definitive establish prima facie a positive re- The algorithm proceeds with an un- step of the algorithm is to block that sponse at O-C1, and one to confirm it. expected question, are confirmatory joint. The block should be performed Given the rarity of O-C1 headaches, blocks positive? This is a point to according to published standards (see and given the scarcity of individuals which the algorithm returns if investi- Technique above). with skills to perform blocks at this level, gations prove positive. If no blocks The first step in evaluating the re- proceeding to this point in the algo- have yet been performed the answer is sponse asks whether the response is rithm should be a rare occurrence. no, which allows the practitioner to partial. This question allows for the In essence, most cases of headache proceed to deeper layers of the algo- possibility of a patient having two con- should be identified within two blocks, rithm. secutive joints painful. In that event the with perhaps up to one-third of patients The next question constitutes a node patient reports complete relief of pain encountering a technical failure. In for reflection. It relies on the practition- in one half or other of their region of other words 50% of patients will re- ers judgement and intuition to cease pain, but no relief in the complemen- quire 2.3 blocks, on the average. Of the blocks if, after other steps in the algo- tary half. This is the only and strict other 50%, a small proportion will prove rithm, there are grounds for doubt meaning of partial (see Interpretation positive to C3-4 blocks, and will require about the propriety of proceeding with above). Partial does not mean incom- no more than three blocks to achieve investigations. At the commencement plete relief of all of their pain. It requires the end-point. Another proportion will of investigations the default answer is complete relief of pain but only in part prove positive at C1-2, and will require no, which allows progress to the next of the anatomical region in which the four blocks to reach that end-point. step. pain is felt. In practice, the patient will The efficiency of the algorithm is such The algorithm asks whether the first report complete relief in the upper half that patients with headache should joint selected has been excluded. If it of their painful region, or in the lower have a diagnosis established, on the has been excluded, the option arises to half. The implication is that a consecu- average, within three blocks. Investi- investigate other joints that might rea- tive joint, below or above the one anaes- gations might be abandoned after fewer sonably be responsible for the pa- thetised, is still painful. than this number of blocks in some tients pain. This step of the algorithm If the response is partial, the algo- cases. The need for four blocks should allows for acceptable errors in judging rithm invites a block of the appropriate be unusual, and would pertain to the the segmental location of the patients adjacent joint: the one below the first rare instances of pursuing O-C1. Oth- pain from the pattern of distribution of joint blocked if only the upper half of the erwise, the need for more blocks than their pain. In this regard, the accept- patients pain was relieved, or the joint average suggests a lack of skill on the able error is + one segment. Thus, a above the first joint blocked if only the part of the practitioner, or an undisci- C6-7 pain may be misread as a C5-6 lower half of the patients pain was plined approach to the problem. pattern, or a C5-6 pattern might be initially relieved. This second block read for a C4-5 pain. For practical carries the same status in the algorithm Part 3: Neck Pain Algorithm purposes, the joints that might reason- as a first block. For the purpose of The initial step in investigating neck ably be expected to account for lower allocating agents under double-blind pain is to interpret the distribution of the cervical pain are the C5-6, C6-7, and protocols, the same agent should be patients pain. If it does not conform C4-5 joints, in that order of prevalence. used for this block of the adjacent joint within reason to a typical pattern of Pursuit of a joint outside this range as was used for the block of the first joint. 59

60 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks Algorithm Part 3: Neck Pain 60

61 Australasian Musculoskeletal Medicine November 2001 Cervical Medial Branch Blocks If the response to the adjacent block believes that they may have made a be made within two blocks. is positive, i.e., it relieves the pain not mistake in selecting the joint to be relieved by the first block, a confirma- blocked, the algorithm allows other References tory block is undertaken. This block joints that might reasonably be the 1. Lord S, Barnsley L, Wallis B, Bogduk should be performed at both the previ- source of pain to be investigated. N. Third occipital headache: a preva- ously anaesthetised levels, and for If the response to any block is posi- lence study. J Neurol Neurosurg both joints the second agent allocated tive, a confirmatory block is performed. Psychiat 1994; 57: 1187-90. under a double-blind protocol should If the confirmatory block is positive, 2. Lord SM, Bogduk N. The cervical be used. a diagnosis is established. synovial joints as sources of post- If the response to the confirmatory If the confirmatory block is negative, traumatic headache. J Musculoskel block is positive, a diagnosis is estab- the algorithm calls for reflection. As Pain 1996; 4: 81-94. lished of double-level pain at consecu- argued above, under these conditions, 3. Bogduk N, Aprill C, Derby R. Diag- tive joints. In this regard, the most proceeding with blocks is inefficient, nostic blocks of synovial joints. In: common of double-level patterns is and the default recommendation is to White AH, ed. Spine Care, Volume C5-6, C6-7. Less commonly, C4-5, cease blocks. One: Diagnosis and Conservative and C5-6 pain may occur together.7-9 Treatment. St Louis: Mosby, 1995, pp. If the response to the confirmatory Part 4: Efficiency 298-321. block is negative, the investigator should Under the operation of this algo- 4. Dreyfuss P, Michaelsen M, Fletcher reflect on the propriety of proceeding rithm, the most common source of D. Atlanto-occipital and lateral atlanto- with further blocks. Implicitly, the pa- lower cervical pain, C5-6, can be diag- axial joint pain patterns. Spine 1994; tient has reported either false-positive nosed within two blocks: one to estab- 19: 1125-31. responses to the first blocks or a false- lish prima facie that the joint is painful, 5. McCormick CC. Arthrography of negative response to the confirmatory and one to confirm the response. In the the atlanto-axial (C1-C2) joints: tech- block. The two possibilities cannot be event that a patient has two consecu- nique and results. J Intervent Radiol distinguished with information avail- tive joints that are painful, the diagnosis 1987; 2:9-13. able. Nor is it legitimate to repeat is established within three blocks: one 6. Barnsley L, Lord SM, Wallis BJ, blocks in an effort to secure a positive each to establish that each of the two Bogduk N. The prevalence of chronic response. One the one hand this sub- joints is prima facie positive, and one cervical zygapophysial joint pain after sequent positive response does not to confirm the response. If an error is whiplash. Spine 1995; 20: 20-26. negate the negative response. Nor can made in judging from the distribution of 7. Bogduk N, Lord SM. Cervical it be refuted that the patient was coached the patients pain which joint is respon- zygapophysial joint pain. Neurosurg into having a positive response. Since sible, the algorithm allows for another Quarterly 1998; 8: 107-17. this conundrum cannot be resolved joint to be selected. In that event, a 8. Dwyer A, Aprill C, Bogduk N. Cer- without multiple investigations starting diagnosis should be established within vical zygapophysial joint pain patterns afresh, investigations should cease in three blocks: the first negative block, I: a study in normal volunteers. Spine the interests of public efficiency. Pur- the second block to establish prima 1990; 15: 453-57. suing multiple blocks in order to resolve facie that the second joint selected is 9. Lord S, Barnsley L, Wallis BJ, a conundrum in one patient denies painful, and one to confirm the re- Bogduk N. Chronic cervical access to investigation to other pa- sponse. At its limit, the algorithm allows zygapophysial joint pain after whip- tients who might prove clearly positive. for two errors in judgement, and the lash: a placebo-controlled prevalence If the response to the initial block is testing of three joints. Under those study. Spine 1996; 21: 1737-45. not partial, its result will be either nega- conditions, either the third selected tive or positive. joint is diagnosed within four blocks, or If the response to the first block is all reasonably possible joints are ex- negative, the algorithm invites consid- cluded within three blocks. eration of whether pursuing investiga- Given that errors in judgement should tions is justified. Given a negative re- be uncommon, the algorithm allows a sponse at the only level that the prac- diagnosis to be established, on the titioner considers likely to be the cause average, within three blocks. The rare of pain, the practitioner might be sat- instances of needing to proceed to isfied that no further investigations are four blocks should be outnumbered by required. If, however, the practitioner the occasions when the diagnosis can 61

62 Australasian Musculoskeletal Medicine November 2001 Muscle Cramp Dr Steve Bentley MBChB, Dip Obst, Dip Sports Med, Dip MSM, FAFMM, Musculoskeletal Physician, Dunedin NZ Abstract Muscle cramp is a common phenomenon experienced by most people at some time in their life. Cramp occurs in a wide variety of conditions and circumstances such as; during prolonged exercise, pregnancy, metabolic disorders (e.g., hypocalcaemia), central nervous system disorders and in certain cases of toxicity or poisoning, reflecting a multifactorial pathogenesis. Since Denny-Brown and Foley demonstrated increased frequency of action potentials on EMG during cramp in 1948 and Norris et al induced cramp using a maximum voluntary contraction with the muscle in a shortened position in 1957, there has been very little worthwhile research on the subject. Muscle fatigue has been shown to affect spinal reflexes, increasing muscle spindle activity and reducing 1b afferent activity from golgi tendon organs. Fatigue also slows the relaxation phase of muscle contraction predisposing to tetany if the firing frequency is maintained or increased. However cramp can still be induced when spinal reflexes are abolished by peripheral nerve block. Cramp may start at several different places simultaneously in a muscle, not within the same motor unit. It is unclear whether muscle cramp may originate at the terminal branches of motor axons, the motor end plate or within the muscle fibres themselves. In some cases the disturbance arises within the CNS. Cramp is a self-limiting condition but can be treated by active or passive stretch. Quinine reduces the frequency of night cramps by up to 43% and also the severity of cramp. Botulinum toxin injection and myofacsial trigger point injections may have a role in treating cramp. Definition M encephalomyelitis, poliomyeli- tion. Relief of cramp can occur by M uscle cramp is the local tis stretching the muscle. The authors ised, involuntary, sustained 7. Suspected neurological disorders commented: It is still uncertain whether and painful contractions of M Stiff Man syndrome (? CNS cramps have their origin in muscle, skeletal muscle, generally of sudden disorder). Cramps can be arrested peripheral nerve or in the spinal cord. onset and characterised by high fre- by curare or peripheral nerve block quency discharges of muscle action M Denny-Brown AND Foley syn- There has been very little research potentials on the electromyogram, re- drome (benign fasciculations and on cramp over the last 50 years. Mus- flecting increased motor unit activity. cramp) cle cramp pathophysiology has yet to 8. Toxicity or poisoning be determined. Myths such as in- Classification of Muscle Cramp M tetanus (peripheral nerve), black creasing salt intake to prevent cramp 1. Night cramps, especially in the eld- widow spider bite have no scientific basis. Electrolyte erly (limb position) M drugs: strychnine (inhibits gly- disturbances at the muscle cellular 2. Exercise-induced muscle cramp cine), danazol, labetolol, beta 2 level during cramp have not been meas- 3. Occupational cramp (e.g., writers, agonists, phenothiazines, lithium ured. Muscle cramp may occur in miners, musicians) carbonate) hyponatraemia due to excessive in- 4. Cramps of pregnancy 9. Peripheral vascular disease take of hypotonic fluids during endur- 5. Metabolic disorders ance sport. M extracellular hypoosmolality, hy- Historical Studies on Muscle Cramp ponatraemia 1940. Quinine was reported by Moss 1986. Maughan4 measured serum M hypocalcaemia, tetany or car- and Herman1 to be effective in treating electrolytes (sodium, potassium and popedal spasms 15 elderly people for nocturnal cramp. bicarbonate), haematocrit and plasma M hyperventilation, respiratory al- volume in 82 runners before and after kalosis (transient fall in free cal- 1948. Denny-Brown and Foley2 dem- a 42.2 km marathon. There were no cium) onstrated increased frequency of ac- differences in the 18% who suffered M hypokalaemia (diuretics, liquo- tion potentials during muscle cramp on cramps and those who did not. rice, carbenoxolone, amphotericin electromyogram. B) 1988. Sontag and Wanner5 proposed 1957. Norris et al reported that 16% of 3 that modern lifestyle and sitting causes 6. Neurological disorders healthy young adults experience night loss of flexibility in the lower limbs. A M spinal cord injury cramps >2x/month. series of case studies is used to illus- M multiple sclerosis, motor neu- Cramp could be induced using a trate the benefit of stretching in patients rone disease maximum voluntary contraction while with chronic muscle cramp symptoms. M neoplasia of CNS the muscle was in a shortened posi- 62

63 Australasian Musculoskeletal Medicine November 2001 Muscle Cramp Observations on Muscle Cramp M Romano and Schieppati8 (1987) lieved by stretch. Following periph- 1. Most individuals experience cramp demonstrated during concentric eral nerve block, cramp was in- at some time in their life. muscle contraction, particularly duced by stimulation distal to the 2. Certain individuals experience when the muscle is in a shortened block and could be relieved by cramp often. Cramp is less com- position and contracting rapidly, stretch despite the nerve block (GTO mon in children. increased spindle activity and mo- 1b afferent blocked). 3. Twitches or fasciculations increas- tor unit recruitment. 2. Roeleveld et al10 (2000) used a ing in frequency may precede M It is likely that chemically induced spatial surface EMG recording cramp. nociceptor stimulus from muscle muscle activity during calf cramp 4. A voluntary contraction of a muscle damage or metabolic stress will which was induced by a maximum in a shortened position can cause cause increased reflex = and C voluntary contraction. The results cramp. motorneuron activity. showed: 5. Muscle cramp can be relieved by M Cramp can start at several places stretch, but not after prolonged ex- Actin-Myosin Contraction Coupling simultaneously in a muscle, may ercise to fatigue. H+ ions produced during intense involve only a small part of the 6. Exercise related cramp occurs in anaerobic exercise from glycolysis muscle and spread slowly activat- endurance events near the end or (particularly type IIB muscle fibres) ing neighbouring muscle fibres, not after the race. have been postulated to cause muscle necessarily whole motor units. 7. Exercise related cramp occurs fatigue by: M The firing rate of motorneurons during intense competition rather 1. Interfering with phosphofructoki- in cramp is higher than during a than in training. nase activity in glycolysis (negative maximum voluntary contraction in 8. Athletes may on occasions run feedback) which the whole muscle is active. through cramp. 2. Competing with Ca2+ for troponin Large motor units have fast twitch 9. Cramp occurs during a concentric binding sites, reducing actin-myosin fibres with shorter action potentials. contraction (e.g., in the calf or toes coupling The high firing frequency during during a kick turn in a pool). 3. Reducing calcium release from the cramp suggests selective recruit- sarcoplasmic reticulum (SR). ment of fast motor units during Various theories on the pathogenesis cramp. The self-limiting character of muscle cramp include CNS excita- Calcium re-uptake to the SR is en- of cramp may be due to rapid tion, increased motorneuron excitabil- ergy (ATP) dependent requiring cal- fatigue of fast twitch fibres. ity and local muscle metabolic, and cium ATPase. Individuals with calcium electrical or motor end-plate distur- ATPase deficiency experience mus- Is the action potential during cramp bances. cle pain following exercise and de- generated at the level of the terminal Research supporting different theo- layed muscle relaxation but not cramp. branches of motor axons or at the ries is scant. Physiological studies on H+ ions may possibly inhibit calcium muscle fibres themselves, rather than muscle may give indirect evidence of ATPase activity, reducing the reuptake by way of whole motor unit activation? possible mechanisms. of calcium to the SR, prolonging mus- cle contraction (hypothesis). Treatment of Muscle Cramp Muscle Proprioceptors and Spinal In a fatigued muscle there is a slower 1. Passive or active stretch. Norris et Reflexes relaxation phase of contraction, mus- al3 1957; Bertolasi et al9 1993. M Nelson and Hutton6,7 (1985/86) ex- cle spindle activity and motor unit re- 2. Quinine. Quinine reduces the fre- amined proprioceptor activity in cat cruitment increases, GTO activity is quency of nocturnal cramps by 21- gastrocnemei muscle stimulated to depressed or abolished. If the firing 43% and reduces the severity of fatigue. The excitatory drive to motor frequency is not reduced, fused sum- cramps. Side effects of tinnitus and units (= and C motorneurons) in- mation and tetany will result. other rare but serious side effects creases as force production falls such as cardiac arrythmia, optic during fatigue. Golgi tendon organ Evidence for a Peripheral Mecha- neuritis, thrombocytopenia, and (GTO) activity is depressed or abol- nism of Cramp convulsions may limit its use. Qui- ished in a fatigued muscle and 1. Bertolasi et al9 (1993) used EMG, nine reduces motor end-plate ex- recovers slowly. This results in un- and induced muscle cramp by vol- citability and increases refractory opposed = and C motor neuron untary contraction of the muscle in period of skeletal muscle contrac- stimulus to motor units. a shortened state. Cramp was re- tion. Man-Son-Hing et al11(1998). 63

64 Australasian Musculoskeletal Medicine November 2001 Muscle Cramp 3. Transcutaneous Nerve Stimulation pregnancy, but there is a lack of marathon runners. J Sports Sci 1986; 4: 31- (TNS). Mills et al12 (1982), in a case evidence of efficacy. In a 34. study, reported the successful ap- double-blind randomised study of 5. Sontag SJ, Wanner JN. The Cause of plication of TNS in aborting wide- 60 pregnant women who were given Leg Cramps and Knee Pains: an Hypoth- esis an Effective Treatment. Med Hypoth- spread chronic cramp of uncertain either 1 g calcium gluconate bid or eses 1988; 25: 35-41. origin. TNS applied between the Vitamin C 1 g bid for three weeks in 6. Nelson DL, Hutton RS. Dynamic and scapulae aborted cramp in the lower the third trimester, all had normal static stretch responses in muscle spindle limbs and elsewhere indicates a serum calcium, magnesium and receptors in fatigued muscle. Med and Sci likely central mechanism for cramp albumin throughout the trial irre- Sport Ex 1985; 17(4): 445-50. in this individual. spective of treatment. There were no 7. Nelson DL, Hutton RS. Stretch sensitiv- 4. Botulinum Toxin. Botulinum toxin differences in symptoms of cramp ity of Golgi tendon organs in fatigued gas- blocks presynaptic release of ace- between the two groups, and cramp trocnemius muscle. Med and Sci Sport Ex tylcholine at motor end plates and symptoms improved in 60% of both 1986; 18(1): 69-74. 8. Romano C, Schieppati M. Reflex excit- has been used to treat muscle groups (Hammar et al17 1987). ability of human soleus motorneurones hypertonicity and cramp. A pro- during voluntary shortening or lengthening spective uncontrolled trial by Summary contractions. J Physiol 1987; 390: 271-84. Bertolasi et all3 (1997), on people M Muscle cramp is common and self- 9. Bertolasi L, et al. The influence of mus- with a benign cramp-fasciculation limiting, affecting most people some cular lengthening on cramps. Ann Neurol syndrome who had botulinum in- time in their life. 1993; 33(2): 176-80. jections to the calf and toe flexors, M A diverse range of conditions af- 10. Roeleveld K, Van Engelen BG, reduced the severity of cramp and fecting different parts of the nerv- Stegeman DF. Possible mechanisms of increased the cramp threshold fre- ous system may cause muscle muscle cramp from temporal and spatial surface EMG characteristics. J Applied quency (to peripheral nerve stimu- cramp. Disturbances in the CNS, Physiol 2000; 88: 1698-1706. lation) for up to three months. spinal reflexes, peripheral nerves 11. Man-Son-Hing M, Wells G, Lau A. 5. Injection of Myofascial Trigger and muscle may all contribute to the Quinine for Nocturnal Leg Cramps. A meta- Points. In a randomised uncon- occurrence of muscle cramp. Mus- analysis including unpublished data. J Gen trolled trial, trigger point injections cle fatigue is important in exercise- Intern Med 1998; 13: 600-606. with xylocaine had a similar effect induced muscle cramp. 12. Mills KR, Newham DJ, Edwards RHT. as quinine on reduction in fre- M There is a lack of scientific knowl- Severe muscle cramps relieved by trans- quency, severity and intensity of edge on muscle cramp pathophysi- cutaneous nerve stimulation: a case re- nocturnal cramps. The effects were ology. port. J Neur Neurosurg and Psych 1982; 45: 539-42. prolonged for over four weeks after M Proven effective treatments of mus- 13. Bertolasi L, et al. Botulinum toxin treat- cessation of treatment (Prateep- cle cramp include stretching, qui- ment of muscle cramps: a clinical and avanich et al14 1999). nine (moderate efficacy but side neurophysiological study. Ann Neurol 1997; 6. Magnesium. Magnesium is not ef- effects). There may be a place for 41(2): 181-86. fective in the treatment of nocturnal botulinum toxin, TNS and trigger 14. Prateepavanich P, Kupniratsaikui V, leg cramps. In a randomised, cross point injection in some cases. More Charoensak T. The relationship between over, double-blind placebo control- research is required. myofascial trigger points of gastrocnemius led trial of 45 subjects with noctur- muscle and nocturnal calf cramps. J Med nal leg cramps, treated with oral References Assoc Thai 1999; 82(5): 451-59. 15. Frusso R, et al. Magnesium for the magnesium citrate 900 mg bid for 1. Moss HK, Herman LG. The use of quinine for relief of night cramps in the extremities. treatment of nocturnal leg cramps: a four weeks and placebo four weeks, JAMA 1940; 115: 1358-59. crossover randomised trial. J Fam Pract there was no difference in the two 1999; 48(11): 868-71. groups in frequency duration or 2. Denny-Brown D, Foley JM. Myokymia and the benign fasciculation of muscle 16. Connolly PS, et al. Treatment of noctur- severity of cramps (Frusso et al15 nal leg cramps. A cross over trial of quinine cramps. Trans Assoc Am Physician 1948; 1999). 61: 88-96. vs vitamin E. Arch Int Med 1992; 152(9): 7. Vitamin E. Vitamin E is ineffective in 3. Norris FH, Gasteiger EL, Chatfield P. An 1877-80. reducing leg cramp frequency, EMG Study of Induced and Spontaneous 17. Hammar M, Berg G, Solheim F, Larsson severity or sleep disturbance Muscle Cramps. Electroenceph Clin L. Calcium and magnesium status in preg- (Connelly16 1992). Neurophysiol 1957; 9: 139-47. nant women. A comparison between treat- 4. Maughan R. Exercise induced muscle ment with calcium and vitamin C in preg- 8. Calcium in Pregnancy. Calcium cramp: a prospective biochemical study in nant women with leg cramps. Int J Vitamin has been used for cramps during Nutr Res 1987; 57: 179-83. 64

65 Australasian Musculoskeletal Medicine November 2001 Management of Chronic Achilles Tendinosis: An Update for Drafting Clinical Guidelines Dr Charles Ng, MB ChB, Dip Sports Med, Dip MSM Introduction not actually describe any specific his- unrelated to the degree of physical A chilles tendinosis is a com- topathological diagnosis and hence loading. Although traditionally thought mon condition affecting should not be used. to be related to overuse, few studies sportsmen and active people Achilles tendinosis describes de- have focused on the role of overuse in as well as the less active. It often affects generative changes in the tendon. the development of chronic tendon the large group of middle-aged (35 There is degeneration and disordered injuries.8 Most studies are retrospec- years+) male recreational sportsmen. arrangement of collagen fibres, focal tive and fail to have a control group. It has a tendency to become chronic, hypercellularity, and vascular prolif- There is usually a gradual onset in that is, lasting more than 1-3 months, eration.3,4 Thus it is a histopathological Achilles tendon pain and swelling. An and is therefore difficult and frustrating diagnosis. This correlates well with acute onset suggests a partial tear of to manage for both doctor and patient. ultrasound and MRI appearances. the tendon. However Astrom3 found The more chronic the condition, the Tendinosis and partial rupture may be partial tendon ruptures were present in worse the prognosis. Surgery may be hard to distinguish. 19% of patients with chronic Achilles resorted to, with unsatisfactory or poor Paratendinitis refers to inflamma- tendinopathy. The partial ruptures al- results. A plethora of treatments has tion of the paratenon sheath through ways occurred in areas afflicted with developed but there are no satisfac- which the tendon slides. It therefore tendinosis. It is plausible that where a tory clinical guidelines demonstrating does not imply any abnormality of the degenerative tendon exists, whether the appropriate indications for the va- tendon itself, although tendinosis and symptomatic or asymptomatic, a par- riety of treatments proposed. paratendinitis can occur together.1 tial rupture of the tendon can develop. This review sets out to define Achilles The terms Achilles tendinopathy Present data demonstrate that tendinosis as distinct from other con- and achillodynia are clinical labels for tendinosis and partial rupture are clini- ditions affecting the Achilles tendon, pain and/or swelling in the Achilles cally and histopathologically indistin- namely tendinitis, paratendinitis, retro- tendon. They could be used initially guishable.3 However total Achilles rup- calcaneal bursitis and tendon rupture. until a more specific diagnosis is made ture cannot be attributed to pre-exist- In doing so, tendinosis may be distin- clinically or with the use of diagnostic ing tendinosis. guished from these other conditions imaging or histologically. In this review chronic tendinosis and therefore treated appropriately. This review will address the diagno- referred to a minimum symptom dura- A review of studies on Achilles sis and management of chronic Achil- tion of one month; the majority of study tendinosis was carried out from a les tendinosis only. cases being in a 12-250 weeks range Medline literature search of studies of duration. published since 1995. Diagnosis Chronic tendon injuries are signifi- Symptoms Definitions cantly more common in ageing ath- Pain occurs most often in the mid- Achilles tendinitis is a term used by letes.8 The peak incidence appears to portion of the Achilles tendon. If se- doctors to describe any condition pre- be between ages 30 and 50 years.3,5 vere, pain occurs with walking, other- senting with pain and swelling in the The ageing tendon is more vulnerable wise its onset is with increasing weight- Achilles tendon area. Therefore, treat- at a given level of physical loading.3 bearing activity, walking, running and ment tends to be empirical using anti- However, Gibbon et al12 found no rela- jumping and landing. There is morning inflammatory medication (NSAIDs) and tionship between the age of the pa- stiffness or stiffness after inactivity. physical therapies which are often tients and the site of disease, suggest- unsuccessful. The terms tendinosis, ing that the predisposing factors to Signs tendinitis, paratendinitis, retrocalcaneal tendon disease are not age related. Tenderness and swelling is found in bursitis need to be distinguished. Male predominance is partly ex- the mid-portion of the Achilles tendon, Achilles tendinitis implies an inflam- plained by a greater participation in ranging from 1.5 cm to 7 cm proximal matory process of the Achilles tendon. sports. However, in men there is a to its insertion in the calcaneus.1,6,9,11 However, biopsies have failed to dem- tripled risk of symptoms developing It can also exist in the proximal and onstrate the presence of inflammatory regardless of the level of physical distal (tendon-bone junction) parts of cells.1 Alfredson et al,2 in a study using activity.3 This condition is also seen in the tendon. Pain and tenderness are microdialysis in tendon tissue, did not patients who do not participate in sports consistent presentations. Swelling was find high levels of prostaglandin E2 to activities or other strenuous leg-load- variable: 80% of subjects had a soft suggest inflammation. So although ing activities.7 Astrom3 found that the tissue swelling at the site of pain.3 tendinitis is a widely used term, it does extent and severity of the lesion were Achilles paratendinitis also presents 65

66 Australasian Musculoskeletal Medicine November 2001 66

67 Australasian Musculoskeletal Medicine November 2001 Management of Chronic Achilles Tendinosis with pain, tenderness and swelling in indicating the severity of the lesion. distal third tendinosis and retro- the same portion of the Achilles ten- They found that imaging was unreli- calcaneal bursitis. Paratendinitis was don. However, the swelling with able in assessing the paratenon and also found to be associated with paratendinitis tends to be more diffuse that MRI is more sensitive, but both give retrocalcaneal bursitis. and remains in a fixed position when similar information. Soila et al13 conducted a MRI study the foot is plantar or dorsiflexed. With Karjalainen et al6 state that ,as le- of 100 normal Achilles tendons and tendinosis the more focal swelling sions in the Achilles tendon and in the described the appearance of tendon and area of tenderness moves be- peritendinous structures can have simi- and peritendinous tissue in asympto- neath the palpating fingers during lar clinical presentation, MRI detects matic individuals. The average AP di- plantar and dorsiflexion of the foot. and characterises these changes. A ameter was 5.2 mm. An area of tendon Pain, swelling, and tenderness in the more specific diagnosis and progno- degeneration was detected in four distal part of the Achilles tendon could sis can be made with the use of MRI cases. Retrocalcaneal bursae con- also be caused by tendinosis.1,3 How- than with clinical examination alone. tained a prominent fluid collection in 15 ever, retrocalcaneal bursitis needs They studied 118 painful Achilles ten- cases. They were able to show the to be excluded and can occur concur- dons with MRI and detected abnor- paratenon in great detail, whereas in rently. Karjalainen et al6 performed malities in 111. Of the 21 who went to abnormal tendons Astrom10 found the MR imaging of Achilles tendon overuse surgery and had proven foci of method unreliable. Therefore normal injuries and demonstrated retrocalcan- tendinosis, 20 were detected on MRI. Achilles tendon anatomy is variable eal bursitis in 83% of patients with In all cases with true-positive MRI find- and may feature degenerative changes insertional tendinosis. Gibbon et al12 ings, the lesion had a disorganised and retrocalcaneal bursae fluid collec- using ultrasonography found 82% had tendon fibre structure. tions in the absence of symptoms. associated retrocalcaneal bursitis. Movin et al11 performed MRI on 20 Hence there is a risk of misinterpreting Based on the clinical presentation patients. All were biopsied and showed findings in symptomatic tendons. and examination findings, a working increased noncollagenous extracellu- Consideration of the clinical presenta- diagnosis can be made on which to lar matrix and altered fibre structure in tion needs to be given in order to formulate a management plan. Any the lesions corresponding to the con- determine the significance of any ab- tendinosis of less than 12 weeks dura- trast-enhanced areas. There was a normal findings. tion and which has been untreated high level of extracellular glycosamino- Some authors suggest ultrasonog- would benefit from a conservative glycans. In summary, Movin felt that raphy and MRI to monitor a tendons management program. If the patient clinical symptoms and signs usually healing response, but Astrom10 feels had received some form of conserva- correlate well with the area of increased that healing is best indicated by relief tive treatment and continued to have signal abnormality seen at MRI. of pain. His results in healed tendons Achilles tendon pain or if there was any Ultrasonography, however, is cheap showed that abnormal imaging was doubt over the diagnosis or other and reliable in experienced hands and compatible with excellent clinical re- tendon disorders were suspected, then therefore should be the first method of sults. Astrom even doubted that there proceed to diagnostic imaging. choice. is any advantage in preoperative Gibbon et al12 performed a retro- imaging as the lesion is easy to identify Imaging spective study of 118 symptomatic clinically and chronic Achilles Achilles tendinosis has a character- heels. They found the ultrasound ap- tendinopathy is almost always caused istic appearance on imaging with ultra- pearance of enlargement and de- by tendinosis. This is not in concord- sonography and MR. However the creased echogenicity of the tendon ance with other studies stating that the indications for which imaging tech- consistent with the histopathological clinical diagnosis may not identify other nique to use and when to use them finding of tendinosis. They stated that Achilles tendon problems.6 remain controversial. high frequency sonography has Astrom et al10 found that chronic greater spatial and contrast resolution Histopathology Achilles tendinopathy is almost always for superficial tendon structures than Biopsies of abnormal Achilles ten- caused by tendinosis. Therefore ultra- does MRI. Ultrasonography is useful dons2,3,6,9,10 show the following com- sonography and MRI are of limited use in distal third Achilles tendon disease mon features: in decisions regarding surgical treat- as 82% of the heels had associated 1. disorganised, irregular tendon fi- ment since the lesion is easily identi- retrocalcaneal bursitis. This suggests bre structure fied clinically, but they may become either a common mechanism of injury 2. separation and lack of continuity of valuable prognostic instruments by or a common causal relationship for the collagen fibres 67

68 Australasian Musculoskeletal Medicine November 2001 Management of Chronic Achilles Tendinosis 3. light collagen staining don pain as being chronic if of more safer medications should be used for 4. roundness of tenocyte nuclei than six weeks duration. This distinc- analgesia. There may be a theoretical 5. active capillary proliferation in some tion was important as more than 90% benefit for the use of NSAIDs in Achil- tendons of acute cases will recover without les tendinosis where there is associ- 6. absence of inflammatory cells surgical intervention. ated paratendinitis or retrocalcaneal 7. increased staining for glycosamino- bursitis. Gibbon et al,12 showed that glycans located extracellularly be- Conservative Treatment 82% of the heels with distal third Achil- tween the collagen fibres. Despite the long-standing use of these les tendon disease had associated conservative treatments, once again retrocalcaneal bursitis. Movin et al9 postulate that the in- there is a lack of randomised controlled creased glycosaminoglycans content studies of their effectiveness.8 Corticosteroid Injections may be a reactive cell response to Once again, as there is no demon- mechanical overloading of the tendon. Biomechanical Abnormalities strable inflammation in Achilles The glycosaminoglycans may reduce Astroms (unpublished) data of 362 tendinosis, there is no justification for the interfibre cohesion of the collagen patients with Achilles tendinopathy and the use of corticosteroid injections. bundles resulting in the observed 147 control patients showed that Corticosteroid injections have been changes in the fibre structure and biomechanical abnormalities were not associated with tendon ruptures. How- arrangement. Therefore tendinosis important in chronic Achilles tendino- ever the relationship between steroid may represent an imbalance between pathy. Therefore the use of orthotics injection and rupture remains contro- matrix synthesis and degradation. was of questionable value. versial. Following the use of corticos- Astroms10 studies in post-mortem teroid injections to treat chronic painful material have indicated that tendon General Recommendations conditions of the Achilles tendon, fre- degeneration is present in up to 30% These include wearing adequate quent partial ruptures have been ob- of asymptomatic individuals. Minor supporting footwear, improving flex- served.19 Astrom20 in a retrospective abnormalities in the tendons of healthy ibility by stretching and correcting train- study of 342 patients with chronic controls have been noted with ultra- ing errors. Relative rest is recom- tendinopathy found that treatment with sonography. Although the gold stand- mended as there is little point in persist- corticosteroid injections was shown to ard for diagnosis of tendinosis is a ing with the same type or intensity of predict a partial rupture. Therefore the histopathological one, the aforemen- exercise if Achilles tendon pain per- concern is whether corticosteroid in- tioned MRI and ultrasonography stud- sists or increases. A modified exercise jections cause partial ruptures of the ies have demonstrated an excellent program with reduced or non-weight- Achilles tendon, or is this merely an correlation between imaging and his- bearing exercises would be recom- association, as the more severe Achil- topathological findings. mended until the tendon pain disap- les tendinopathies are the ones that pears. tend to be injected. The more severe Management cases are the ones that have severe Physical therapies like ultrasound, Medications degenerative changes and pre-exist- electrical stimulation, cold therapy, heat NSAIDs ing partial tears. Achilles tendon tears therapy, frictioning and massage have These are frequently used for the following corticosteroid injections are all been proposed for chronic Achilles treatment of soft tissue inflammation, likely to occur if the patient mobilises tendinosis. However there is an ab- in particular conditions of tendinitis. excessively or too soon following an sence of randomised controlled trials However, the histopathological appear- injection. If corticosteroid injections to demonstrate their effectiveness. ance of Achilles tendinosis shows the are given for paratendinitis and The general consensus from the absence of inflammatory cells,9 and retrocalcaneal bursitis, there may be a limited number of studies available microdialysis technique showed nor- case for immobilising the ankle joint in recommend conservative (nonsurgi- mal prostaglandin E2 levels.1 Based on a functional brace after an injection. cal) treatment initially and that surgical this consistent finding from many stud- The duration of bracing and its effi- treatment be used if there is no im- ies, there would appear to be no indi- cacy would need to be confirmed in provement after 3-6 months of con- cation for the use of NSAIDs for their controlled trials. servative treatment.14-17 The average anti-inflammatory effect. Any benefit duration of symptoms from onset to would be from their analgesic effect.1,18 Exercise therapy surgery was 12 months. However, as they are associated with Almekinders8 reviewed studies us- Johnston et al14 defined Achilles ten- frequent gastrointestinal side effects, ing exercise therapies for chronic ten- 68

69 Australasian Musculoskeletal Medicine November 2001 Management of Chronic Achilles Tendinosis don injuries but could not find any crease in the pain score during activity strength was not measured, and there prospective controlled studies. Re- (from 81.2 +/- 18.0 to 4.8 +/- 6.5 ). The was no comparison or control group. cently however, Alfredson et al5 re- calf muscle strength on the injured side However the Angermann study did ported excellent results from a pro- had increased significantly, not differ- have a longer-term follow-up of five spective trial studying the effect of ing much from the non-injured side. years (range 33-72 months), whereas heavy-load eccentric calf muscle train- Despite the small study numbers Alfredson had only a 12-week follow- ing for the treatment of chronic Achil- (n=15), the favourable results from the up period. les tendinosis. They studied 15 rec- heavy-load eccentric calf muscle train- reational athletes (12 men and three ing were statistically significant. Eccentric Exercise Training women, mean age 44.3 years +/- 7 From the Alfredson study, some years) who had a diagnosis of chronic Heavy-load Eccentric Calf Muscle questions need to be answered. Why Achilles tendinosis with a long duration Training did these patients benefit significantly of symptoms (18.3 months, range 3- Due to its effectiveness, a more from their eccentric calf muscle train- 100 ). They had pain on running and detailed description of the training pro- ing? What is the theoretical benefit of had tried conventional conservative gram is warranted. eccentric muscle training? treatment consisting of rest, NSAIDs, Patients were instructed on how to Research suggests that eccentric biomechanical correction, physical do the eccentric training by physical exercise may be of benefit in rehabili- therapy and ordinary training pro- therapists. There were also written tation of musculoskeletal injuries.20 grams, with no effect on the Achilles instructions. Three sets of 15 repeti- During exercise, the maximum load is tendon pain. The comparison group tions were performed twice a day, placed on a tendon during the eccen- consisted of 15 recreational athletes seven days per week for 12 weeks. tric phase, making it likely that injury to (11 men and four women) with a From an upright body position and a tendon occurs during eccentric load- younger mean age of 39.6 +/-7.9 years. standing (facing a step) with all body ing.5 Eccentric loading promotes col- This group also differed in having a weight on the forefoot and the ankle lagen formation throughout the ten- longer duration of symptoms (33.5 joint in plantar flexion, the calf muscle don, thereby increasing the elastic months, range 6-88), so it was not an was loaded by having the patient lower and tensile properties of the tendon.20,23 identical control group. This group had the heel beneath the forefoot/step level. Remodelling of the tendon, whether tried the same conventional treatments The calf muscle was loaded eccentri- healthy or pathological, as in tendinosis, as the study group without any relief of cally only, no following concentric load- is induced by eccentric loading. This the Achilles tendon pain. They were ing was done. Instead, the noninjured reference also suggested that a com- rested from treatment for the three- leg was used to get back to the start bination of eccentric and concentric month period prior to undergoing sur- position. Patients were to continue the activations would be more effective. gery. All patients had Achilles tendon exercises even with pain, stopping Concentric activations should be used pain for at least three months and an only if the pain was disabling. When prior to eccentric training, which should area of tendinosis located 2-6 cm they were relatively pain free doing the be started when the muscles improve above the Achilles tendon insertion. exercise, they increased the load by their strength, due to the high tension The diagnosis of tendinosis was con- adding weights. development during eccentric firmed by ultrasonography. activations. Also eccentric training at Calf muscle strength and the amount Other Exercise Programs fast angular velocities compared with of pain during activity (recorded on a The results of this exercise program slow speed training was recommended, 100 mm visual analogue scale) were were superior to that of Angermann as slow speed eccentric loading gen- measured before the onset of training and Hovgaard.15 Their graduated train- erated excessive tension and regula- and after 12 weeks of eccentric train- ing program followed a period of heel tory demand. However, Alfredson5 did ing. At week 0, all patients had Achilles elevation, massage and triceps surae not feel that eccentric exercise was tendon pain preventing running and stretching. The duration of the training velocity dependent and achieved ex- there was significantly lower eccentric program was until the patient was able cellent results with loading applied at and concentric calf muscle strength on to return to sports or a maximum of six slow speed. Alfredson is regularly per- the injured compared with non-injured months. The exercise program included forming follow-up ultrasounds on his side. After the 12-week training pe- heel-raises as in the Alfredson study. study group in order to detect struc- riod, all 15 patients were back at their However, it was not specific in empha- tural changes in the tendon related to pre-injury levels with full return to run- sising the eccentric phase of the heel- eccentric training. ning. There was a significant de- raise exercise, isokinetic calf muscle 69

70 Australasian Musculoskeletal Medicine November 2001 Management of Chronic Achilles Tendinosis Recommendations from Eccentric abnormal tendon tissue which is ex- Complications of Surgery Loading cised. A side-to-side suture is then The complication rate from surgery From this study, a number of recom- used to repair the area of excision. has been reported between 4.7 and mendations can be made for the man- The result from surgery is variable. 13%.1,7 Skin edge necrosis, wound agement of chronic Achilles tendinosis. Kvist21 reported 20% of surgically infection, haematoma, deep venous Patients with long duration of symp- treated patients requiring re-opera- thrombosis and Achilles tendon rup- toms (mean 18.3 months, range 3-100 tion, with 3-5% forced to give up their ture have occurred. Alfredson in an- months) responded well to the training athletic careers due to persistent de- other study22 found that 12 months program. bilitating pain. Johnston et al14 re- following surgery for chronic Achilles This suggests that it is still worthwhile ported that all 17 study patients who tendinosis, bone mineral density of the persevering with conservative treat- had soft tissue tenolysis and/or exci- calcaneus was found to be 16.4% ment for at least three months from the sion of degenerative tendon cysts were lower at the injured side. time of presentation before consider- able to return to unrestricted activity ing any surgical treatment. During after 31 weeks. Maffulli et al16 per- Summary of Management Guide- these three months, the patient should formed surgical decompression of lines undertake the prescribed exercise pro- chronic central core lesions of the The aim of this review is to formulate gram described above. This recom- Achilles tendon. Their study group of a draft clinical practice guideline for mendation is in contrast to other stud- 14 athletes had a long duration of the treatment of chronic Achilles ies14-16 where the longer the duration of symptoms, average 87 months. At fol- tendinosis. The reason for this is that Achilles tendinosis symptoms, the less low-up, only five had a good result. the condition is relatively common, yet favourable the response to conserva- They recommended that surgery be clinical management of it is unsatisfac- tive treatment, and surgery was rec- performed earlier. tory and at times inappropriate. Unsat- ommended if no progress was being Maffulli et al17 in a different study isfactory treatment results in chronicity made after 3-6 months. The surgical performed percutaneous longitudinal of symptoms, disability, and less fa- studies stated that if surgery was not tenotomy in runners. Multiple longitu- vourable outcomes. Inappropriate treat- undertaken by the 3-6-month stage, dinal incisions were made in the area ment includes persisting with some then it was less likely that there would of maximal swelling. This is thought to forms of physical therapies and anti- be a favourable response to surgery. be beneficial in improving the local inflammatory medication when there is The training program is safe and circulation of the tendon. However, no proven benefit or evidence of in- easy to perform. It is cost effective, not only 17 of the 52 patients in the study flammation. This also represents a requiring medication or intensive thera- had tendinosis demonstrated on ultra- waste of valuable resources and a risk pist input, and it allows the patient to be sound and the results do not specify of side effects from use of anti-inflam- in active control of their treatment. The the outcome of the tendinosis group. matory medication. program also fits in well as a logical The surgical studies recommend Most of the time chronic Achilles step in the rehabilitation ladder prior to surgical treatment of chronic Achilles tendinosis can be diagnosed clini- the patient returning to the impact- tendinopathy if symptoms persist after cally. Chronic tendinopathy clinically loading of walking and running. 3-6 months of conservative treatment, correlates well with tendinosis demon- claiming that further delay in surgery strated on ultrasonography, MRI and Surgical Treatment results in a less favourable outcome. histopathological examination. Be- Surgery is needed in about 25% of However as shown by Alfredson et al,5 cause of this, it is unnecessary and cases of chronic painful conditions of conservative treatment with eccentric once again a waste of resources per- the Achilles tendon - not specifically calf muscle training was very effective forming ultrasonography and MRI tendinosis.21 Surgery is more likely for for patients with an average duration of merely to diagnose chronic tendinosis. the older patient, longer duration of symptoms of 18 months. Bearing in Imaging should be performed only if symptoms and the presence of mind the comparatively poorer results the condition has failed to respond tendinopathic changes. from surgery and the possible compli- after at least three months of eccentric The surgical technique usually in- cations, even the more chronic cases calf muscle training and surgery is volves a straight longitudinal skin inci- of Achilles tendinosis should undergo being contemplated. In tendinosis sion medial to the Achilles tendon. The at least three months of an eccentric affecting the distal third of the tendon, paratenon is incised. Any abnormal calf muscle training program before imaging is useful to identify frequently paratenon tissue is excised. A central proceeding to surgery. associated retrocalcaneal bursitis longitudinal tenotomy then exposes any which may respond to other forms of 70

71 Australasian Musculoskeletal Medicine November 2001 Management of Chronic Achilles Tendinosis conservative treatment. Prior to sur- and histopathologic findings. Clin don: results of conservative and surgi- gery, ultrasonography is the most cost- Orthop 1995; 316: 151-64. cal treatments. Foot and Ankle Internat effective form of imaging to localise the 4. Khan KM, Cook JL, Bonar F, et al. 1997; 18(9): 570-74. area of tendinosis and to detect any Histopatholgy of common tendino- 15. Angermann P, Hovgaard D. associated retrocalcaneal bursitis. pathies: update and implications for Chronic Achilles tendinopathy in ath- Some authors suggest ultrasonog- clinical management. Sports Med 1999 letic individuals: results of nonsurgical raphy and MRI to monitor healing re- Jun; 27 (6): 393-408. treatment. Foot and Ankle Internat sponse but Astrom10 feels healing is 5. Alfredson H, Pietila T, Jonsson P, 1999; 20(5): 304-306. best indicated by relief of pain. His Lorentzon R. Heavy-Load Eccentric 16. Maffuli N, Binfield P, Moore D, King results in healed tendons showed that Calf Muscle Training for the Treatment J. Surgical decompression of chronic abnormal imaging was compatible with of Chronic Achilles Tendinosis. Am J central core lesions of the Achilles excellent clinical results. Sports Med 1998; 26 (3): 360-66. tendon. Am J Sports Med 1999; 27(6): Tendinosis is not peculiar to the 6. Karjalainen PT, Soila K, Aronen H, 747-52. Achilles tendon, so an understanding et al. MR imaging of overuse injuries of 17. Maffulli N, Testa V, Capasso G, et of this condition will assist in the man- the Achilles tendon. Am J Roentgenol al. Results of percutaneous longitudi- agement of tendinopathies at other 2000; 175: 251-60. nal tenotomy for Achilles tendinopathy sites like the shoulder, elbow and pa- 7. Rolf C, Movin T. Etiology, histology, in middle- and long-distance runners. tella. The principles of management of and outcome of surgery in Achillodynia. Am J Sports Med 1997; 25(6): 835- chronic Achilles tendinosis may apply Foot Ankle Int 1997; 18 (9); 565-69. 40. equally to the other sites. 8. Almekinders L, Temple J. Etiology, 18. Astrom M, Westlin N. No effect of Formulation of clinical practice guide- diagnosis, and treatment of tendinitis: piroxicam on Achilles tendinopathy: a lines is limited by the quality of evi- an analysis of the literature. Med and randomised study of 70 patients. Acta dence-based clinical studies. Many of Sci in Sports and Exercise 1998; 30 Orthop Scand 1992; 63: 631-34. the studies are merely retrospective (8): 1183-90. 19. Leadbetter WB. Anti-inflammatory clinical observations. Some are pro- 9. Movin T, Gad A, Reinholt F, Rolf C. therapy and sports injury: the role of spective trials, but lack adequate con- Tendon pathology in long-standing non-steroidal drugs and corticosteroid trol groups or the size of the study achillodynia. Acta Orthop Scand 1997; injection. Clin Sports Med 1995; 14: group is too small for any useful con- 68 (2): 170-75. 353-410. clusions to be made. 10. Astrom M, Gentz C, Nilsson P, et al. 20. Kellis E, Balzopoulos V. Isokinetic The level of evidence of all the avail- Imaging in chronic Achilles eccentric exercise. Sports Med 1995; able studies in the references is either tendinopathy: a comparison of ultra- 19(3): 202-22. level III-3 or level IV.24 Prospective sonography, magnetic resonance 21. Kvist M. Achilles tendon injuries in randomised controlled clinical studies imaging and surgical findings in 27 athletes. Sports Med 1994; 18(3): 173- (providing level I evidence) are re- histologically verified cases. Skeletal 201. quired to allow a better comparison of Radiol 1996; 25: 615-20. 22. Alfredson H, Nordstrom P, Pietila the various treatment methods. This 11. Movin T, Kristoffersen-Wiberg M, T, Lorentzon R. Bone mass in the will help in optimising outcome and Rolf C, Aspelin P. MR imaging in calcaneus after heavy loaded eccen- resource utilisation. chronic Achilles tendon disorder. Acta tric calf-muscle training in recreational Radiologica 1998; 39: 126-32. athletes with chronic Achilles References 12. Gibbon W, Cooper J, Radcliffe G. tendinosis. Calcif Tissue Int 1999; 64: 1. Alfredson H, Lorentzen R. Chronic Distribution of sonographically de- 450-55. Achilles Tendinosis: recommendations tected tendon abnormalities in patients 23. Brukner P, Khan K. Clinical Sports for treatment and prevention. Sports with a clinical diagnosis of chronic Medicine. 1995: p. 433. Med 2000 Feb; 29 (2): 135-46. Achilles tendinosis. J Clin Ultrasound 24. A guide to the development, imple- 2. Alfredson H, Thorsen K, Lorentzen 2000; 28: 61-66. mentation and evaluation of clinical R, et al. In situ microdialysis in tendon 13. Soila K, Karjalainen P, Aronen H, practice guidelines. Canberra; National tissue: high levels of glutamate but not et al. High-resolution MR imaging of Health and Medical Research Council, prostaglandin E2 in chronic Achilles the asymptomatic Achilles tendon: new 1998. tendon pain. Knee Surg Sports observations. Am J Roentgenology Traumatol Arthrosc 1999; 7: 378-81. 1999; 173: 323-28. 3. Astrom M, Rausing A. Chronic Achil- 14. Johnston E, Scranton P, Pfeffer G. les Tendinopathy: a survey of surgical Chronic disorders of the Achilles ten- 71

72 Australasian Musculoskeletal Medicine November 2001 Autologous Chondrocyte Implantation in the Management of Articular Cartilage Defects Mr Ian Henderson, Orthopaedic Surgeon, Director, Orthopaedic Research Department, St Vincents & Mercy Private Hospital, Melbourne Introduction acceptable or reliable treatment for use in humans and confirmed clinical Tissue engineering has been de- articular cartilage injury, resulting in efficacy with follow up to nine years. scribed as the manipulation, manufac- inevitable deterioration and the onset Peterson demonstrated that isolated ture or alteration of cells, tissues or of osteoarthritis. femoral condyle defects gave the best organic substances for human implan- Pharmacological agents for results with less success for osteo- tation. intraarticular injections, such as corti- chondritis dissecans and patients with Autologous chondrocyte implanta- costeroid, hyaluroric acid and cross- lesions associated with ACL rupture tion (ACI) is a tissue engineering ap- linked hyaluroric acid (Synvisc) have and subsequent reconstruction. There proach to the treatment of full thickness been studied; however, none of these was no evidence of deterioration with articular cartilage defects and is the has shown positive effect beyond short- time and improved results were seen first clinically proven application of term symptomatic improvement. with patella defects when alignment tissue engineering in orthopaedics. Techniques have been developed to was corrected. The structure of articular cartilage is attempt to initiate repair in articular Subsequently Peterson reported the well known. It consists of chondrocytes cartilage; however, these are ineffec- clinical results of 59 ACI patients at the surrounded by a complex extra cellular tual in the long term and result in 1997 AAOS meeting.9 Most of these matrix of type II/IX collagen, with large fibrocartilage formation only. patients had failed prior conventional water retaining aggrecan molecules Pluripotential cell recruitment by surgery of either debridement or creating a unique structure ideally microfracture appears to be affective microfracture. The ACI patient results suited for the lining of articular sur- in terms of pain relief in the short term, were either excellent or good for 95% faces. This structure is capable of but produces fibrocartilage of limited of femoral condyle defects, 89% of withstanding significant forces and has durability.2,3 osteochondritis dissecans and 75% of regional variation in thickness and stiff- Local joint replacement using osteo- femoral condyle defects in association ness, according to functional require- chondral grafts (mosaicplasty) has with ACL reconstruction. Biopsy re- ments in the joint. proven technically challenging with vealed the presence of hyaline-like Articular cartilage has no blood sup- incomplete incorporation of grafts and repair and biomechanical assessment ply, lymphatic drainage, or neural ele- subsequent replacement of surface using the arthroscopic indentometer ments and articular chondrocytes are hyaline cartilage by fibrocartilage of of Lyyra (Artscan 1000)10 demon- ineffective in responding to injury. limited efficacy. strated that the stiffness of hyaline Whilst there may be transient cell rep- The preferred process is to regener- repair (2.77N) was comparable to that lication and local increased matrix ate articular cartilage using isolated of normal articular cartilage (3.08N) synthesis in response to injury, at the autologous chondrocytes or whole tis- and substantially greater than that of margin of the lesion, there is no effec- sue with chondrogenic potential, such fibrous repair (1.23N) tive reparative process unless the as perichondrium or periosteum.4 No These patients were treated by what subchondral bone is penetrated allow- long-term studies on periosteal graft- has become known as the Peterson ing an inflammatory response with cell ing have been published to date and Technique. This consists of arthro- recruitment from the marrow elements. this procedure is often associated with scopic harvest of articular cartilage This response is usually incomplete, complications such as graft hypertro- from non-weightbearing areas of the fails to restore normal hyaline cartilage phy, chondrification, and ossification. knee or the periphery of the lesion to but results in the formation of fibrocar- be treated, release and expansion of tilage which fails as an articular sur- Autologous Chondrocyte Implan- chondrocytes in the laboratory, face in the long-term.1 tation reimplantation of free cells at arthrotomy Damage to articular cartilage of the Autologous chondrocyte implanta- after preparation of the lesion and knee is common, including the large tion (ACI) as a technique for regener- coverage using periosteum harvested area of loss caused by osteochondritis ating articular cartilage in humans was from the proximal tibia or distal femur. dissecans, which can lead to prema- developed from the early animal stud- The periosteum is sutured in place and ture arthritis. 1 ies of Grande5 and Brittberg,6 which sealed with fibrin adhesive. Cell Whilst elderly patients with low de- verified the efficacy of cultured populations appropriate to the volume mand can be successfully treated chondrocytes in enhancing the repair of the lesion are cultured and instilled symptomatically and functionally by of articular cartilage defects treated beneath the periosteal patch in a volume joint replacement, there are many pa- with periosteal grafting in rabbits. of medium acceptable to the lesion and tients in the young and middle age Subsequently Brittberg and Peterson containing the optimum number of cells groups for whom there is usually no in 19947 and 19988 reported clinical (see Figs. 1a, 1b, and 1c). 72

73 Australasian Musculoskeletal Medicine November 2001 Autologous Chondrocyte Implantation Following reimplantation, the limb is rested for 24 hours to allow adherence of the cells, followed by a progressive rehabilitation program beginning with continuous passive motion and progressing to ambulation with regulated re- stricted weightbearing and a progressive activity program over 12 months. Patients with tibiofemoral lesions must remain non-weightbearing for six weeks, followed by a six- week period of protected weightbearing in an un-loading brace. At three months normal daily activities can be resumed; however, high demand activities are restricted for six months. Return to sport is permitted at 12 months. Patients with patellofemoral lesions can weightbear as tolerated in an extension splint, but must avoid bent knee activity for three months. The rehabilitation program re- quires carefully supervised physiotherapy.11 While patients largely self-select by presentation the Figure 1(a). Native lesion. procedure is recommended for patients between the ages of 15 and 55 who have a well-circumscribed lesion or lesions in an otherwise essentially normal joint, with sur- rounding articular cartilage suitable for suture of the perio- steal patch. Full thickness articular cartilage lesions greater than 1 cm2 on the femoral condyle, trochlea or patella where subchondral bone is intact are most suitable. Multiple lesions are acceptable and femoral condyle and trochlea lesions commonly treated at the same time. Patellofemoral lesions are acceptable and Kissing lesions are accept- able, providing the opposing surface defect is no greater than grade II Outerbridge. Tibial plateau lesions provide technical difficulties at this time due to access restrictions for periosteal patch suture. However, some anterior lesions have been treated successfully with or without associated ligamentous release. The procedure is contraindicated in patients with gener- alised osteoarthritis or inflammatory disease, crystal dis- Figure 1(b). Prepared lesion. ease, or chondrocalcnosis. Angular deformity resulting in medial or lateral compartment overload must be corrected and patella femoral dysfunction or instability must be addressed. Morbid obesity, defined as >150% ideal body weight, is a contraindication. The clinical use of ACI has been developed in several centres in Europe and the United States. There are now several companies actively developing a commercial prod- uct, including Verigen Tissue Sciences in Denmark, Codon in German, Educell in Slovenia and Genzyme Corporation (Carticel), Advanced Tissue Sciences, Intregra Life Sciences Corp. and Lifecell Corp. in the USA. ACI Clinical Results Clinical data are available from both European and North American patient series. Those in the North American studies have been assessed using a modified Cincinnati Figure 1(c). Sutured patch. Knee Score with patient and clinician assessment. The 73

74 Australasian Musculoskeletal Medicine November 2001 Autologous Chondrocyte Implantation European experience has assessment Hypertrophy of the repair site pro- scopically. Clinical assessment showed using modified Cincinnati Knee Score duced clinical symptoms in seven cases a modified Cincinnati Knee Score of and four other validated clinical scor- (6%). This was treated by arthroscopic good/excellent in 28 patients (86%) ing systems (Lyschholm, Wallgren, debridement which did not affect the and ICRS score for degree of defect Tegner, Brittberg.) The European re- final outcome. repair at arthroscopy of 10.2/12. Two sults have also included arthroscopic Peterson subsequently presented patients were classified as failures. second look, biopsy for histology, two year results of 213 ACI patients in biochemical analysis and biomech- March 2000.12 The results on modified North American Experience Febru- anical assessment using indent- Cincinnati Knee Score were good/ ary 2001 ometry.10 excellent for 90% of femoral condyle Data from the International Cartilage lesions, 74% of femoral condyle + Repair Registry (ICRR) presented at Swedish Experience May 200011 ACL, 84% of OCD, 69% of patella, the AAOS February 200114 now in- The clinical arthroscopic and histo- 58% of trochlea and 75% multiple clude 1300 patients. Of these 42 are at logical results were reported from fol- lesion. Patella lesions were dependent 60 months follow up and data for 36 of low up of 110 implantations in the first upon normal mechanics and the re- these were available. 101 patients treated in Sweden for full- sults of trochlea lesions were influ- The patients had been assessed on thickness chondral defects of the knee enced by size of the lesion. four criteria without arthroscopy or ranging from 1.5 cm2 to 12 cm2 follow- Forty-six repair sites were inspected biopsy. Patient and clinician evalua- ing the introduction of ACI in 1987. Of at second look arthroscopy and evalu- tion using modified Cincinnati Knee this group 93 patients were clinically ated on the ICRS scale, allowing four Score with pre- and post-operative evaluated, 65 underwent arthroscopic points each for the three parameters, assessments, assessment of patients assessment and 37 of these agreed to level with surrounding cartilage, com- symptoms and knee examination. core biopsy of repair tissue and histo- plete integration and arthroscopically The 36 patients with five-year follow logical assessment. normal appearance of the surface. up, on MCKS showed improvement on The assessment of ACI in the study The mean score was 10.5 out of a clinician and patient evaluation of 3.1 consisted of clinical outcome quanti- possible 12. to 7.2, and 3 to 6.8 respectively. There fied by the five validated grading scales Nineteen repair site biopsies were was no change in these patients be- listed, macroscopic characteristics of carried out with histologic hyaline re- tween 12 and 60 months follow up, the repair tissue assessed at pair tissue in 74% of patients, with a indicating that the initial improvement arthroscopy and histological examina- strong correlation (0.73) between hya- was maintained for at least five years. tion of the repair tissue from core line repair and good/excellent clinical Patient symptoms showed dramatic biopsies. rating. improvement in pain score by an aver- Histological assessment was per- Indentometry was carried out on 14 age of 3.2 points (P

75 Australasian Musculoskeletal Medicine November 2001 Autologous Chondrocyte Implantation drilling or microfracture procedures, A correlation between histological efit analysis. previously considered the best treat- structure of articular cartilage tissue in Whilst the current application has ments available. the knee and indentation stiffness has been predominantly to the knee, exten- The most common adverse events been demonstrated and can be re- sion of indications for ACI is occurring (

76 Australasian Musculoskeletal Medicine November 2001 Autologous Chondrocyte Implantation There are future requirements for 4. ODriscoll SW. Cartilage regenera- tion verses debridement for full thick- the establishment of rigorous clinical tion through periosteal transplantation. ness articular cartilage lesions of the trials, preferably randomised, control- Paper presented at Articular Cartilage femur: Results at 3 years. Poster 146, led and blinded, with inclusion of fur- Regeneration Symposium, AAOS, San ORS, San Francisco, February 2001. ther assessment criteria using clinical, Francisco, California, February 1997. 16. Gillogly S, Newfield D. Treatment of MRI, arthroscopic, histopathologic, and 5. Grande DA, et al. Healing of experi- articular cartilage defects of the knee biomechanic techniques. mentally produced lesions in articular with autologous chondrocyte implan- The basic science of ACI is well cartilage following chondrocyte trans- tation. Medscape Orthop and Sports defined, the clinical application is now plantation. Anat Rec 1987; 218: 142- Med 2000; 4(2). becoming accredited, and the nine 48. 17. Zorzi C, et al. Tissue engineered year results are superior to alternative 6. Brittberg M, et al. Rabbit articular cartilage grafting: Preliminary clinical treatments for articular cartilage in- cartilage defects treated with autolo- data. ICRS 3rd Symposium, April 2000. jury. There appears to be minimal gous cultured chondrocytes. Clin 18. Radosavijevic D. Transplantation adverse events or potential complica- Orthop 1996; 326: 270-83. of human autologous chondrocytes tions of this procedure. Clinical 7. Brittberg M, et al. Treatment of deep cultivated in vitro. Paper presented at progress needs to continue to be as- cartilage defects in the knee with au- ICRS 3rd Symposium, Gothenburg, sessed with the use of detailed out- tologous chondrocyte transplantation. Sweden, April 2000. comes databases. New Eng J Med 1994; 331: 889-95. 19. Knutsen G, et al. Autologous Whilst articular cartilage regener- 8. Peterson L. Paper presented at the chondrocyte transplantation in the knee: ated by current techniques does not meeting of the International Cartilage histological and clinical follow up. Pa- appear to exactly reproduce hyaline Repair Society, Boston, Massachu- per presented at ICRS 3rd Symposium, cartilage, the hyaline-like articular setts, November 1998. Gothenburg, Sweden, April 2000. cartilage that is produced demonstrates 9. Peterson L. Current approaches 20. Joachim G, et al. A one to three satisfactory mechanical load charac- and results of chondrocyte transplan- years follow-up of 119 patients treated teristics with good function and dem- tation. Paper presented at Articular with autologous chondrocyte trans- onstrated long-term durability. Cartilage Regeneration Symposium, plantation using Co.Don Chondro- Whilst current methods of applica- AAOS, San Francisco, California, transplant. Paper presented at ICRS tion have limitations, this is the basis for February 1997. 3rd Symposium, Gothenburg, Sweden, future development, and the availabil- 10. Lyyra T, et al. Indentation instru- April 2000. ity of autologous chondrocyte will en- ment for the measurement of cartilage 21. Bahuad J, et al. Autologous able progress in this field as tissue stiffness under arthroscopic control. chondrocyte implantation (ACI) for engineering application in orthopaed- New Eng Phys 1995; 17: 395-99. cartilage repair on 28 cases. Paper ics develops. 11. Peterson L, et al. Two to nine year presented at ICRS 3rd Symposium, outcome after autologous chondro- Gothenburg, Sweden, April 2000. References cyte transplantation of the knee. Clin 22. Ludvigsen T. Autologous chondro- 1. Mankin HJ. Current concepts re- Orthop and Related Res 2000; 374: cyte implantation for treatment of car- view. The response of articular carti- 212-34. tilage defects in the knee. Paper pre- lage to mechanical injury. J Bone and 12. Peterson L, et al. Durability of sented at ICRS 3 rd Symposium, Joint Surg 1982; 64-A: 460-66. autologous chondrocyte transplanta- Gothenburg, Sweden, April 2000. 2. Kim HKW et al. The potential for tion of the knee. Paper presented at 23. Ferruzzi A, et al. Autologous regeneration of articular cartilage in AAOS, Orlando, Florida, March 2000. chondrocyte transplantation: our ex- defects created by chondral shaving 13. Peterson L. Osteochondritis perience at Rizzoli Orthopaedic Insti- and subchondral abrasion. An experi- dissecans of the knee treated with tute. Paper presented at ICRS 3rd Sym- mental investigation in rabbits. J Bone autologous chondrocyte transplanta- posium, Gothenburg, Sweden, April and Joint Surg 1991; 73-A: 1301-15. tion. Paper presented at ISAKOS, 2000. 3. Steadman JR, et al. Long-term re- Montreaux, May 2001. 24. Winalski C, et al. Utility of magnetic sults of full-thickness articular carti- 14. Mandelbaum B. Cartilage Repair resonance imaging for postoperative lage defects of the knee treated with Registry 7th Annual Report. Paper pre- assessment of autologous chondro- debridement and microfracture. Pa- sented at AAOS, San Francisco, Feb- cyte implantation: MR-Arthroscopic per presented at the Linvatec Sports ruary 2001. correlation. Paper presented at ICRS Medicine Conference, Vail, Colorado, 15. Browne J, et al. A controlled study 3rd Symposium, Gothenburg, Sweden, February 1998. of autologous chondrocyte implanta- April 2000. 76

77 Australasian Musculoskeletal Medicine November 2001 Autologous Chondrocyte Implantation 25. Dahlberg L, et al. Contrast-en- 36. Cherubino P. Matrix induced au- hanced MRI in cartilage repair. Paper tologous chondrocyte implantation: a presented at ICRS 3rd Symposium, new approach to tissue engineering of Gothenburg, Sweden, April 2000. damaged cartilage. Paper presented 26. Bashir A, et al. MR imaging of at APOA, Adelaide, Australia, April glycosaminoglycan in patients with 2001. autologous chondrocyte transplants. 37. Ochi M, et al. Treatment of osteo- Paper presented at ICRS 3rd Sympo- chondral defects in the knee with trans- sium, Gothenburg, Sweden, April plantation of cultured autologous 2000. chondrocytes embedded in collagen 27. Robinson D, et al. Magnetic reso- gel. Paper presented at SICOT, Syd- nance appearance of autologous ney, Australia, April 1999. chondrocyte implants. Paper pre- 38. Hunziker EB, Rosenberg LC. Re- sented at ICRS 3 rd Symposium, pair of partial-thickness defects in ar- Gothenburg, Sweden, April 2000. ticular cartilage: cell recruitment from 28. Mandelbaum B, et al. Three year the synovial membrane. J Bone and multicentre outcome of autologous Joint Surg 1996; 78-A: 721-33. chondrocyte implantation of the knee. 39. Hunziker EB, Kapfinger E. Re- Paper presented at AAOS, Orlando, moval of proteoglycans from the sur- Florida, March 2000. face of defects in articular cartilage 29. Mandelbaum B, et al. Autologous transiently enhances coverage by re- chondrocyte implantation of the knee: pair cells. J. Bone and Joint Surg 3 year outcomes for isolated lesions of 1998; 80-B(1): 144-50. the femur. Poster presented at AAOS, San Francisco, February 2001. 30. Kiviranta I, et al. Indentation analy- sis of the repair tissue after autologous chondrocyte transplantation. Paper presented at ORS, San Francisco, February 2001. 31. Peterson L. Articular cartilage transplantation 13 years experience. Paper presented at APOA, Adelaide, Australia, April, 2001. 32. Briggs T, et al. Autologous carti- lage transplantation: histological evalu- ation. Paper presented at APOA, Ad- elaide, Australia, April 2001. 33. Spring BJ, et al. Biomechanical evaluation of normal articular cartilage in the human knee. Paper presented at APOA, Adelaide, Australia, April 2000. 34. Peterson L. How I treat an ankle cartilage defect. Paper presented at Workshop III, ICRS 3rd Symposium, Gothenburg, Sweden, April 2000. 35. Giannini S, et al. Autologous chondrocyte transplantation in osteo- chondral lesions of the ankle joint in young active patients. Paper presented at AAOS, San Francisco, February 2001. 77

78 Australasian Musculoskeletal Medicine November 2001 The Stiff Painful Shoulder: Capsular Contracture Or Hyperactivity of Shoulder Musculature Greg Schneider, Southern Tablelands Specialist Manipulative Physiotherapist, Braidwood NSW C ontracture of the capsule of GROUP I GROUP II the shoulder is a recognised ERP non-ERP cause of gross movement restrictions of passive shoulder motion Case LR MR Case LR MR in all planes.1 The fibrous contracture is most marked in the region of the 1 100 G.T. 1 350 L3 subscapularis muscle and bursa,2,3 2 500 PSIS 2 (-50) L5 causing lateral rotation of the shoulder to be the most restricted movement.4 3 00 L5 This condition with fibrous contracture is termed frozen shoulder. Table 1. Individual scores for lateral rotation (LR) and medial rotation (MR) for the two Contracture and adhesions are not cases in Group I with equivalent rotation patterns (ERP), and the three cases in Group II present in every case of clinically with non-equivalent rotation patterns (non-ERP). diagnosed frozen shoulder.5 Misdiag- patients are shown in Table 1. Results nosis and confusion occur in cases Three patients were classified into The two patients in Group I had an resembling contracture. These patients Group II. The range of lateral rotation improvement in the ranges of LR over may present with global restriction of for each of these patients was also less 24 hours, but there was a decline to shoulder mobility, but detailed exami- than two-thirds. There was a subtle pre-blockade status by seven days, nation reveals causes other than con- difference in the range of medial rota- and these two patients failed to progress tracture.3 tion in these Group II cases compared (Table 2). Subsequent arthroscopic This study observed five patients to those in Group I. The range of medial investigation of these two cases deter- with stiff painful shoulders diagnosed rotation was restricted, but it exceeded mined that the cause of the movement as frozen shoulders. The cases were the two-thirds S1 limit. Each patient restriction of the shoulder was con- separated into two groups on the basis was able to reach his radial styloid tracture of the joint capsule. of a subtle difference in the pattern of cephalad beyond the S1 level. This Each patient in Group II, with non- movement restrictions. There was also restricted movement pattern was termed equivalent restrictions, gained a sig- a difference between the groups in a non-equivalent rotation pattern (non- nificant improvement in the range of their response to cervical joint block- ERP) (Table 1). LR over 24 hours, and maintained the ade. The outcomes form the basis for Each of the five patients, two in improvement at seven days. a research proposal. Group I and three in Group II, was The individual scores at seven days given an ipsilateral C5/6 zygapophys- show gains of 450, 700, and 400 (Table Method eal joint block, of 10 ml of Bupivacaine 3). Five patients with stiff painful shoul- under radiological image intensifica- The three patients in Group II be- ders were selected. Each patient had tion. The ranges of lateral rotation and came pain free and recovered normal a global restriction of passive shoulder medial rotation for each patient were shoulder mobility within one month. movements in all planes. Subtle differ- measured at two weeks and immedi- This was a highly significant outcome. ences in movement patterns were ob- ately preceding blockade. Measure- Each of the three cases had a nine- served and the patients were identified ments were repeated at three intervals month history of considerable pain as two groups. after blockade. and disability, unresolving, and had Two patients were classified into Group I. The range of lateral rotation for both patients was less than two- INTERVAL CASE 1 CASE 2 thirds, or 600. The range of medial rotation, measured by the hand behind PRE 10 50 back test(HBB) was also less than two- thirds. This two-thirds limit was set 2 HR 60 60 arbitrarily as the radial styloid of the 24 HR 60 70 patients wrist reaching to the level of S1 on the vertebral column. This pat- 7 DAYS 10 65 tern of movements was identified as an equivalent rotation pattern (ERP). The Table 2. Individual lateral rotation scores for the two cases in Group I with confirmed contracture. The scores were recorded immediately preceding blockade (PRE) and at 2 measured ranges of motion for both hours, 24 hours, and 7 days post cervical blockade. 78

79 Australasian Musculoskeletal Medicine November 2001 The Stiff Painful Shoulder strictions of shoulder movement will be INTERVAL CASE 1 CASE 2 CASE 3 selected. Each case will be classified according to movement restrictions. PRE 35 (-)5 0 The patients will be differentiated into 2 HR 75 55 40 two categories. a) Those patients presenting with an 24 HR 75 60 50 equivalent rotation pattern, having both LR and MR restricted to less 7 DAYS 80 65 40 than two-thirds, with LR being the GAIN 45 70 40 more restricted. b) Those patients identified with a non- Table 3. Individual lateral rotation scores for the three cases in Group II with non- equivalent rotation pattern with LR equivalent rotation patterns (non-ERP). The scores were recorded immediately preceding limited to two-thirds, and MR also blockade (PRE), and at 2 hours, 24 hours, and 7 days post cervical blockade. Gains in the ranges of LR of 450, 700, and 400 were recorded for cases 1, 2, and 3 respectively. being restricted but exceeding two- thirds. Each case will receive an arthro- been told to wait two years for recov- SLR by producing hamstring spasm.10 scopic investigation of the shoulder ery. If these principles are applied to the joint. findings in the present study, a hypo- Subsequently each case will be given Discussion thetical model can be proposed. an ipsilateral C5/6 medial branch block The two Group I patients, with con- Through the mechanism of conver- with the ranges of shoulder movement firmed contracture, presented with gence, noxious stimuli from a sympto- assessed before, and at set intervals equivalent restrictions (ERP) of medial matic C5/6 ZJ may be interpreted as after blockade. and lateral rotation. Both cases failed pain arising from the shoulder re- Two hypotheses will be tested using to respond to cervical blockade. gion.11 a two by two contingency table. The three Group II patients, who The motor neurone pools from the H1 a non-equivalent pattern signals presented with non-equivalent rotation shoulder muscles acting across the negative capsule involvement. patterns (non-ERP) had a good re- scapulo-humeral joint, and supplied by H2 non-equivalent cases respond to sponse to cervical blockade. the C5 and C6 cervical nerves may be C5/6 blockade. These outcomes suggest that fac- facilitated, producing hyperactivity or tors other than the capsule contributed spasm, which could restrict shoulder References to the movement restrictions seen in movement. Tonic spasm of subscapu- 1. Noel E, Thomas T, Schaeverbelle T, the Group II patients with non-ERP, laris would limit LR.12 et al. Frozen shoulder. Joint Bone and also suggest a relationship with the Anaesthetisation of the C5/6 ZJ de- Spine 2000; 67: 393-400. cervical spine. The limitations of this creases of blocks discharges from the 2. Bunker TD. Frozen Shoulder: Un- introductory study permit no conclu- joint afferents. ravelling the enigma. An R Col Surg sions. The findings can be discussed This blockade relieves the somatic Engl 1997;79: 210-13. only in a theoretical sense. referred pain to the shoulder, allows 3. Wiley AM. Arthroscopic appear- Some research findings are perti- relaxation of the subscapularis activ- ance of frozen shoulder. Arthroscopy nent to this discussion. The cervical ity, permitting an increase in LR of the 1991; 7: 138-43. ZJs are capable of producing pain and shoulder. 4. Shaffer B, Tibone JE, Kerlan RK. somatic referred pain.6 C5/6 pain ex- This hypothetical proposal has a Frozen Shoulder: A long term follow tends from the base of the neck, across weak link. It invokes a model for a up. J Bone Joint Surg Am 1992; 74A: the supraspinous fossa of the scapula, neuromuscular mechanism for move- 738-46. to the region of the deltoid muscle.6 ment restriction at the shoulder which 5. Haeri GB, Maitland A. Arthroscopic Anaesthetisation of the C5/6 ZJ re- has not yet been validated. findings in the frozen shoulder. J lieved patients of lower neck pain and Rheumatol 1981; 8: 149-52. referred pain to the shoulder.7 The Conclusion 6. Dwyer A, Aprill C, Bogduk N. Cer- actual prevalence of cervical ZJ point The findings from this observational vical zygapophyseal joint pain patterns could be as high as 63%.8 Spasm in study of a small sample of patients I: A study in normal volunteers. Spine diverse shoulder muscles has been prompt further research, which will be 1990; 15: 453-57. elicited by stimulation of cervical ZJs.9 undertaken within the following format. 7. Bogduk N, Marsland A. The cervical Pain arising from lumbar ZJs can limit A sample of patients with global re- 79

80 Australasian Musculoskeletal Medicine November 2001 The Stiff Painful Shoulder zygapophyseal joints as a source of neck pain. Spine 1988 ;13: 610-17. 8. Aprill C, Bogduk N. The prevalence of cervical zygapophyseal joint pain. A first approximation. Spine 1992; 17: 744-47 9. Wyke B. Neurology of the cervical spinal joints. Physiother 1979; 65: 72- 76. 10. Mooney V, Robertson J. The facet syndrome. Clin Orthop 1976; 115: 14956. 11. Bogduk N. In: Ruth Grant, ed. Physical therapy of the cervical and thoracic spine. Innervation and pain patterns of the cervical spine. Churchill Livingstone, 1988, p. 5. 12. Bogduk N. Anatomical and neuro- physiological features of the neck- shoulder symptom complex. Proceed- ings of neck shoulder pain sympo- sium. Sydney, 1981, pp. 455-51. 80

81 Australasian Musculoskeletal Medicine November 2001 Thoughts on Soft Tissue Pain Dr Peter Jackson, Musculoskeletal Physician, Brisbane* Introduction ducted to assess current opinion about overlying skin and subcutaneous tis- I t doesnt take long for naive musc- the myofascial pain syndrome (MPS). sue. He found that mechanical and uloskeletal physicians to realise The objectives of the study were to chemical stimulation of fascial that gapping spinal facet joints, as determine whether MPS was a legiti- nociceptors caused well-defined lo- important as this is in management of mate disorder, whether it was distinct calised pain referred just distally to the acute spinal pain or for providing a from the fibromyalgia syndrome(FMS), area of stimulation. Mechanically stimu- window of opportunity for managing and whether the participants believed lating subtending muscle nociceptors chronic pain, is not the solution for that a limited core of symptoms or caused slight but more diffuse pain, most patients who seek care. They signs could readily characterize it. Of which was greatly enhanced in terms gradually become aware of the huge the 403 respondents, 88.5% believed of perception and distal referral by problem that they have been taught that MPS was a legitimate diagnosis. chemical stimulation. nothing about, namely, soft tissue pain. Eighty-one percent believed that MPS Kellgren found that chemically stimu- We and our other medical colleagues and FMS are distinct from each other. lating muscle nociceptors caused both are standing knee deep in this prob- The survey further indicated that the localised and more diffuse referred lem. We read about it in medicolegal signs and symptoms essential to the pain and certain of these muscles reports and hear other medical prac- diagnosis of MPS were a regional referred pain to joints. The infraspina- titioners dismiss it in vaguely disparag- location pattern of symptoms, the pres- tus caused deep shoulder joint pain ing terms. ence of trigger points (TrP), and a whereas the vastus medialis caused So, what is soft tissue pain? Well, two normal neurological examination. These (the enigmatic) knee pain. Further- different but overlapping conditions findings imply that the study respond- more he was able to induce visceral are the source of soft tissue pain. ents were properly distinguishing the pain. When he injected the multifidae These are the fibromyalgia syndrome specific condition MPS, defined by at L1/2 his subject felt testicular pain. and myofascial syndromes of indi- trigger points, from the improper ge- Kellgren believed that this pain was vidual or regional groups of muscles. neric usage of the term myofascial referred via intramuscular septa, as he pain, which has come to loosely mean was unaware of substance P, Nomenclature all soft tissue pain conditions. To sensitisation of dorsal horn transmis- Soft tissue pain, fibromyalgia, and codify avoidance of this common form sion neurones, and expansion of re- myofascial pain arent very good terms confusion, it has been recommended ceptive fields. because they are vague, a bit old- that the term soft tissue pain (STP) be The medical profession, not being fashioned, and dont appeal to the adopted as the relevant generic term. able to verify these observations with scientifically minded practitioner. Pos- laboratory tests and x-rays, ignored sibly fibromyalgia should be called Discussion these observations and felt that psy- central sensitisation. Myofascial pain Soft tissue pain has had numerous chogenic rheumatism was the most should be called functional muscle descriptions over history that were a appropriate rubric. This time was also nociceptor sensitisation syndrome. reflection of the time and culture. Rheu- the decade of the disc under the Until better names come along, how- matism, cellulitis, fibrositis, and influence of Cyriax and Mixter and ever, I shall use these older terms. Its myodysneuria are a few examples. Barr, which diverted attention to bone a pity that just as these names are Currently, the myofascial pain syn- and joints as the source of muscu- gaining common currency they be drome component of soft tissue pain loskeletal pain. deleted from the medical lexicon. can be considered a regional pain An Australian, Michael Kelly, was A few years ago I was talking to a syndrome and a true neuromuscular one of the insightful few to acknowl- Medecin sans Frontieres doctor in disorder. edge Kellgrens observations and made Morocco about fibromyalgia. He told Myofascial pain syndrome can be contributions to understanding me that in Africa fibromyalgia is called tested by specific needle EMG, sur- myofascial pain until his last paper in There Disease. When an African face EMG, ultrasound, and algometry. 1962. I like to think of this as the first tribesman is asked, where do you Modern understanding of myofascial flowering of musculoskeletal medicine hurt he would indicate, there, there, pain began in the 1930s when Profes- in Australia, the second episode, start- and there, pointing to unrelated areas sor John Kellgren, working in London, ing with Murtagh and Kenna in 1985. In of the body. investigated the effects of stimulating New Zealand, Professor Barry Tait A recent survey1of American Pain nociceptors in fascia and its subtend- and the organised medical profes- Society members, who regularly care ing muscle by mechanical and chemi- sions battle with the ACC to prevent lay for patients with body pain, was con- cal means after first anaesthetising the practitioners becoming preferred pro- 81

82 Australasian Musculoskeletal Medicine November 2001 Thoughts on Soft Tissue Pain viders of musculoskeletal medicine neurones and the myofascial cells or inhibition. were similar influential events. developed from common embryological Spasm or inhibition can be referred Concurrently, Janet Travell, a suf- stem cells. This could explain why the to other muscles independent of pain ferer of shoulder muscle trigger points convergent transmission neurones referral and this can be identified with found similar problems in bed-ridden see pain in distal muscles. Further- surface electromyography. A trigger tuberculosis and chest pain patients more there can be a vague myotomal point in the infraspinatus can strongly which she and her cardiologist col- distribution of pain evoked from trigger inhibit the anterior deltoid during shoul- league, Rinzler, treated with procaine points. For example, scalene trigger der flexion, which can nevertheless be injections and/or spraying the overly- points can produce referred pain simi- normally recruited during shoulder ing skin with ethyl chloride spray (to lar to C6/7 radiculopathy or gluteus abduction. Another common example stimulate cutaneous temperature minimus anterior trigger points can is active trigger points in the quadratus receptors) and passively stretching cause referred pain similar to L5 lumborum causing neurological inhibi- the underlying muscle. They simply radiculopathy. tion of gluteal muscles. Surface elec- described the problem as tender tromyography indicated a return to spots in muscles. Needle Electromyography normal function after the trigger points It was a professor of orthopaedic Various studies in humans and rab- were deactivated and can facilitate surgery from Iowa who nominated ten- bits have confirmed low amplitude retraining by biofeedback. der points in muscles that referred pain noise activity that is highly charac- as (the gluteal) myofascial syndrome teristic of myofascial trigger points but Algometry around 1940. not pathognomonic. When this noise Algometry does not indicate the cause Later, Travell collaborated with is associated with high amplitude spikes of tenderness, does not provide an Simons, a person with postgraduate it is a strongly confirmatory finding. absolute value, requires great palpatory electromyograpic training, in progress- skill to position the footplate over the ing the understanding of the patho- Ultrasound point of maximal tenderness, and re- physiology of myofascial TrP pain. Two researchers have visualised a quires a standardised rate of applica- Studies indicate that the prevalence local twitch response in taut band fi- tion because fibromyalgia patients tend of TrP pain in selected patient bres with the use of high-resolution to report pain at less pressure. populations is quite common. The ultrasound. In one study the twitch was Algometry helps with acquiring in- problem in a general medical popula- elicited by needle penetration of a formation about pain thresholds of tion has been found to be 30%, in a trigger point in a taut band of an active and latent trigger points and pain medicine centre 93%, in a head infraspinatus muscle. The transient normal muscles. There is consider- and neck pain clinic 55% and in a contraction coincided with the patients able overlap of these three types of lumbogluteal orthopaedic clinic 21%. verbal report that he felt his typical pain pain threshold measurements. It is believed that direct stimuli by and experienced a referred pain to his acute or chronic muscle overload, shoulder and arm. Interrater Reliability radiculopathy and trauma stimulates Studies of interrater reliability for the group 4 (similar to cutaneous C fibres) Surface Electromyography myofascial pain syndrome component muscle nociceptors to produce an af- Trigger points are associated with of soft tissue pain have been poor. ferent drive into the dorsal horn con- three disturbances of muscle function, These need to be deconstructed to vergent transmission neurones. These which can be assessed by surface provide a more insightful view. The first neurones have active and inactive electromyography. study by Wolfe et al involved four very synapses connected to primary affer- 1. Increased responsiveness experienced examiners but who were ent neurones. When substance P is 2. Delayed relaxation self taught, i.e., not formally trained. released at the active or open synapses 3. Increased fatigueability. They had no chance to agree on a and sensitises the cell wall of the con- In addition, trigger points can pro- technique for examining trigger points vergent transmission neurone the in- duce referred spasm (induced muscle and in fact the design of the study active or silent synapses open up, activity) and referred inhibition in other prevented them from discussing their which results in the development of muscles via central reflex mechanisms. techniques prior to the study. new receptive fields in distal muscles. This observation supports earlier ob- The second study by Nice et al The exception is in the neck where the servations by Janda of a predictable involved examination of three sites in receptive fields are proximal. stereotypical response of muscles to the thoracolumbar paraspinal muscles It is possible that the dorsal horn nociceptor traffic with either tightness of 50 patients with low back pain by 12 82

83 Australasian Musculoskeletal Medicine November 2001 Thoughts on Soft Tissue Pain experienced physiotherapists. Before Distinguishing Features have comorbid fibromyalgia. the patient examination, a practice The female: male ratio for fibromyalgia The concentration of substance P in session was held to allow the therapists sufferer years is 4-9: 1 and for the CSF of fibromyalgic patients is up to practise this method on each other myofascial pain syndrome 1: 1. The to four times normal, although this is until they felt capable. There was no female predominance in fibromyalgia not so in myofascial pain syndrome evaluation of uniformity of technique. may reflect this genders increasing patients. The former patients are The examiners were experienced but likelihood to seek help and higher inci- equally tender in locations other than inadequately trained. dence of hypermobility. Fibromyalgia the mandated 18 tender points, whereas The third study by Njoo et al reported pain is widespread and general, in- non-trigger point sites in myofascial the examination of the quadratus cluding all four quadrants of the body pain patients have normal pain thresh- lumborum and gluteus medius by two plus the fifth quadrant which encom- olds. They are abnormally tender only examiners. An experienced general passes visceral pain, such as reflux at sharply circumscribed TrP sites and practitioner trained four medical stu- oesophagitis, irritable bowel syndrome, specific sites of referred tenderness. dents for three months. From the pool irritable bladder syndrome, and dys- of the trainer general practitioner and menorrhoea. The Neuromuscular Junction his students, two were chosen to per- Pain of myofascial trigger points is Sensory nerves, autonomic nerves form the examination. Essentially, four regional. The difference between the and blood vessels accompany motor of the five examiners were well trained two can be observed from a pain nerve fibres. The junctional endplate but inexperienced. The kappa scores diagram. The markings made by the can be localised by an EMG recording were better but not good. fibromyalgia are all over the body rep- an initially negative deflection. Both Gerwin et al conducted a study with resentation and even outside it in a sides of the endplate have positive first four experienced examiners under the diffuse non-dermatomal and non- deflections. They are found in the mid- assumption that they employed the myotomal way. Markings on a region of each muscle fibre. same examination techniques. They myofascial pain diagram are very spe- Dysfunction of the neuromuscular achieved the same poor results. They cific, commonly just a line or a dot or junctions is now thought to be the undertook a second study but this time a recognisable pain pattern. cause of trigger points. High ampli- participated in a three-hour training Fibromyalgia patients have widespread tude, high-speed EMGs using special- session and achieved statistical agree- tenderness whilst TrP tenderness is ised needle techniques have revealed ment before proceeding. They then very focal. The muscles of fibromyalgia two significant components to the elec- repeated the study and achieved good patients are soft and doughy whilst trical activity. Intermittent and variable kappa scores (.44-.88). A more recent those of MPS are tense and ropy with high amplitude spike potentials super- well-designed study of headache2 a restricted range of motion, and imposed over a consistently present achieved kappa scores of .74-1.0. whereas the joints of fibromyalgia pa- lower amplitude noise-like component Palpating for myofascial trigger tients are distinguished by their has been identified at trigger points. points requires the same skill as listen- hypermobility those of MPS are the These spike potentials had negative ing for heart sounds or palpating foetal reverse. Fibromyalgia patients are initial deflections. Muscle adjacent to parts in a pregnant uterus. Could one examined for the mandatory tender trigger points is electrically silent. When imagine the kappa scores of cardiolo- points whilst myofascial pain syndrome a voluntary contraction is initiated, gists or obstetricians if they did not patients are examined for stereotypi- muscle fibres that are initially recruited have a standardised training scheme? cal trigger points that are predomi- nearly always exhibit the spontaneous To obtain reliable clinical results stud- nantly in the middle of the muscle belly electrical activity outlined above. These ies should employ both experienced or entheses of muscles. These trigger fibres are known as Cinderella fi- and trained examiners who have been points commonly have an immediate bres. This would suggest the possibil- tested for interrater reliability before beneficial response to injections of ity of excitable motor neurones. the study is conducted. The necessary local anaesthetic or local anaesthetic Excessive acetylecholine has been skill can be learned and Fricton, in a with glucose. Fibromyalgia patients identified as the cause of this increased diagnostic study of masticatory frequently have an adverse response electrical activity, which has also been myofascial pain, found that experi- to focal injections and then a delayed called acetylecholine noise. It has enced raters were more reliable than and poorer response. Seventy-two been estimated that the noise-like elec- inexperienced ones and concluded per cent of these fibromyalgia patients trical discharge is caused by 1000- that palpatory findings are technique have active trigger points, whilst 20% fold increase in the rate of release of sensitive. of myofascial pain syndrome patients acetylecholine from a motor nerve ter- 83

84 Australasian Musculoskeletal Medicine November 2001 Thoughts on Soft Tissue Pain minal. fibres. system results in the chronic fatigue It has been proposed that clinically A trigger point can be considered a seen after traumatic episodes. identified trigger points consist of complex containing sarcolemmic con- Neurones in the reticular system multiple abnormal endplates evidenc- traction knots in a taut band, which have bifurcating axons, which project ing spontaneous electrical activity and exhibit electrically active loci. They are downwards to the ventral horn motor are scattered among uninvolved nor- found at the motor point or endplate neurons and upwards to the higher mal endplates. zone of the muscle. A taut band of centres. This may set up increased Spikes occur when a sufficient muscle fibres extends from this central tone in muscles, which may activate number of acetylecholine packets are TrP to the attachment at each end of the Cinderella fibres in which trigger released and summate to depolarise the involved fibre, which with sustained points develop. There is evidence that the post junctional membrane suffi- tension induces a localised enthes- trigger points develop in pre-existing ciently to initiate a propagated action opathy, or attachment TrP. This is tight bands rather than create them. potential in the muscle fibre. where patients point to their pain, for In the reticular formation the old tract example, the lateral epicondyle or stimulates the nuclei reticularis Distribution greater trochanter. They dont point to gigantocellularis and raphe magnus to The endplate zone of a muscle can the middle of the wrist extensors or produce serotonin, the locus coeruleus be electrically identified. Trigger points gluteal group. to produce noradrenaline and the in taut bands can be clinically identi- If enthesopathic attachment trigger periaqueductal grey to produce opioid fied. Using spontaneous electrical points alone are treated without treat- peptides. These substances, via de- activity with or without spikes, it has ing the Central TrP, recurrence of scending pathways, exert a calming been shown that dysfunctional symptoms can be expected. Attach- effect on the dorsal horn transmission endplates are four times more com- ment trigger points have not been stud- cells, preventing spontaneous activity mon where taut bands and the endplate ied properly and their nature is not yet and keeping unwanted receptive fields zone intersect than elsewhere in the understood and cannot be assumed to closed. muscle. No dysfunctional endplates display similar characteristics as the This old tract carries noxious infor- were observed in taut bands outside central TrPs. mation from myofascial tissue (syn = the endplate zone. deep somatic tissue, fibromuscular The Pain System for Dummies tissue) but not from skin and subcuta- Histopathology Nociceptive information travelling neous tissues. It is this system Trigger points in dog muscle have upstream from the dorsal horn is trans- (myofascial tissue, old spino-reticular been studied and have revealed iso- mitted through two separate pathways tract and reticular formation) that is lated fibres and groups of enlarged that have evolved over time, the old associated with the development of round muscle fibres on cross sections. spino-reticular and the new spino-tha- chronic pain. This may occur by pri- Longitudinal sections of the same TrP lamic tract. The former arises from mary failure or acute nociceptor im- areas revealed segments of muscle lamina 5, 7, and 8 and carries nox- plosion (whiplash) or chronic nocicep- fibres with extremely contracted iously generated information arriving tive traffic (internal disc derangement). sarcomeres, which showed a corre- at the dorsal horn by C and the similar By contradistinction, the newly sponding increase in diameter of the group 4 sensory afferents which ini- evolved pathway arises from laminae 1 muscle fibre and abnormally decreased tially terminate in transmission neu- and 5 where A-d fibres terminate, muscle fibre diameter on either side of rones in lamina 1 and 2 then via poly- cross the cord without poly-synapting it. The sarcomeres on either side of the synaptic pathways to the above- and ascends directly to the thalamus contraction knot showed compensa- mentioned deep lamina. From here and thence to the topographically or- tory elongation and narrowing when information ascends in the old tract ganised somatosensory cortex to pro- compared to adjacent normal muscle until it reaches the reticular system and duce an ah ah experience. For ex- fibres. Sarcomeres within a contrac- thence to higher centres such as the ample, I have stubbed the tip of my left tion knot are markedly shorter and hypothalamus, thalamus, limbic sys- little toe and I think its going to hurt wider than the in neighbouring normal tem (pain tolerance), and frontal lobe (from my past experience). This sys- muscle fibres which are free of con- (attitude to pain). The parasympathetic tem, A-d cutaneous nociceptors, spino traction knots. Sarcolemma between nervous system which controls rest, thalamic tract and somatosensory cor- contraction knots is empty of contrac- digestion, reproduction and freezing tex is not involved in the process of tile elements. These contraction knots also originates in this area and I often chronic pain. Have you ever heard of are scattered among normal muscle wonder whether overstimulation of this a chronic pain syndrome resulting 84

85 Australasian Musculoskeletal Medicine November 2001 Thoughts on Soft Tissue Pain from a chronic skin ulcer? fibres, the fast conducting Ab fibres. Guide to Diagnosis and Management. This has been described as fast blocks Churchill Livingstone, 2001. Conclusion slow. Soft tissue pain may be thought of as Myofascial trigger points are satisfy- References two different but associated condi- ing to treat. One only needs to me- 1. Harden RN, Bruehl SP, Gass S, et tions. The most challenging from a chanically deactivate the Central trig- al. Signs and symptoms of the clinical point of view is the fibromyalgia ger point and if one also treats the myofascial pain syndrome: A national syndrome. The other, which is much attachment trigger points, so much the survey of pain management providers. more satisfying to treat, is myofascial better. The mechanical deactivation Clin J Pain 2000; 16: 64-72. pain syndromes of muscles or groups can occur with any means at ones 2. Marcus DA, Scharff L, Mercer S, of muscles. disposal such as dry needles, wet Turk DC. Musculoskeletal Abnormali- Fibromyalgia may be seen as pri- needles, Beaver blades, medial branch ties in Chronic Headache: A Control- mary and secondary. Primary burning devices and emerging tech- led Comparison of Headache Diag- fibromyalgia occurs spontaneously nologies such as IDET. After all, nu- nostic Groups. Headache 1999; 39: without a history of physical or emo- cleus fibrosis laminae are a form of 21-27. tional trauma and may be associated fascia. There is no inflammation so that with failure of the descending inhibi- steroids are of no help and local anaes- * Email: [email protected] tory pathway. There seems to be a thetic, whether short, medium or long genetic component to fibromyalgia. acting, cheap or expensive is more for Secondary fibromyalgia appears to the benefit of the doctor than the pa- develop after sudden unexpected or tient. Tight bands of myofascial tissue chronic afferent nociceptor drive onto surrounding facet joints are most likely the dorsal horn from deep somatic the cause of minor intervertebral dys- tissues including myofascial tissue. function, the osteopathic lesion and This afferent drive seems to overpower the chiropractic lesion resulting in the tonic inhibitory endogenous pain the clinical observation of tenderness, system. Probably the commonest asymmetry, reduced motion and in- cause of this afferent drive is ne- creased tissue tension abnormality. glected or untreated myofascial trig- Mobilisation with impulse, osteopathic ger points. Whilst there is no periph- muscle energy techniques and post- eral pathology in the fibromyalgia syn- isometric relaxation techniques may drome there is an increase in sub- have their effect by stretching these stance P in the interstitial spaces of the tight bands. For example, if the multifidie spinal cord and CSF. There may also and short intersegmental fibres of the well be cellular changes such as sprout- psoas are relieved, if only temporarily, ing, remodelling, and apoptosis but the enigmatic joint blockage will van- who is going to perform a spinal tap or ish. If afferent drive from myofascial cord biopsy to find out? trigger points can be treated properly Some people with fibromyalgia do and promptly, thus preventing central respond to physical medicine tech- sensitisation, the subsequent need for niques and it is probably the abolition repetitive bone cracking and of peripheral afferent drive from a multidisciplinary pain clinic attendance myofascial trigger point that is the may well be dramatically reduced. cause of this improvement. Otherwise one is left with trying to activate the Resources descending inhibitory system by cog- Mense S, Simons D, Russell IJ. Mus- nitive behavioural therapy (synonym = cle Pain: Understanding Its Nature, Indahling), small doses of tricyclic Diagnosis, and Treatment. Lippincott antidepressants to increase the en- Williams & Wilkins, 2001. dogenous noradrenaline and improve sleep and relying on aerobic exercises Baldry PE. Myofascial Pain and to stimulate activity in the pleasure Fibromyalgia Syndromes: A Clinical 85

86 Australasian Musculoskeletal Medicine November 2001 Journal Abstracts This section aims to update the reader with some of the more significant musculoskeletal research published in the last year which is listed on the Medline and CINAHL databases. HIP Magnetic resonance imaging is a structured and semistructured ques- Fink MG, Kunsebeck H, Wipperman non-invasive imaging modality with tionnaires, and underwent neurologic B, Gehrke A. Non-specific effects of clear contrast and superior spatial reso- examination after 1 week and 1, 3, 6, traditional Chinese acupuncture in lution. These characteristics are espe- and 12 months. After 3 to 4 years, osteoarthritis of the hip. Comp Ther cially useful for detecting pathology of participants with whiplash injury were Med 2001; 9; 82-88. the soft tissue of the knee joint, such as questioned about legal issues. the menisci, ligaments and articular Results. After 1 year, 11 (7.8%) Objectives. The effectiveness of cartilage, which are difficult to diag- persons with whiplash injury had not acupuncture treatment in patients with nose using plain x-ray examination. returned to usual level of activity or osteoarthritis of the hip was tested. MRI has become one of the first choice work. The best single estimator of Design: This is a prospective, random- diagnostic modalities for the internal handicap was the cervical range-of- ized, controlled, patient- and investi- derangement of the knee joint, and is motion test, which had a sensitivity of gator-blinded clinical trial. generally replacing some invasive 73% and a specificity of 91% (p < Patients and Setting.The study was arthrographic or arthroscopic exami- 0.01, Cox regression analysis). Accu- performed at a university department nation. Pathology of the articular car- racy and specificity increased to 94% for physical medicine and rehabilita- tilage cannot yet be depicted clearly by and 99% when combined with pain tion. Sixty-seven patients were sepa- MRI. We expect further development intensity and other complaints. This rated into two treatment groups. of the spacial resolution of MRI to make increase was gained at the expense of Interventions. Group I (treatment) possible the detection of chondral le- a reduced sensitivity. Initiation of law- had traditional needle placement and sions more clearly and precisely in the suit within first month after injury did manipulation, whereas in group 2 (con- near future. not influence recovery . trol) needles were placed away from Conclusion. The cervical range-of- classic positions and not manipulated. motion test has a high sensitivity in In both groups needles were placed SPINE prediction of handicap after acute within the L2 to LS dermatomes. Out- Kasch H, Bach FW, Jensen TS. whiplash injury. The value of cervical come parameters were: pain (VAS), Handicap after acute whiplash in- range-of-motion test is further improved functional impairment (hip score), jury. A l-year prospective study of by additional recording of symptoms. activity in daily life (ADL) and overall risk factors. Neurol 2001; 56: 1637- satisfaction before treatment, and 2 43. weeks and 2 months after treatment. PAIN Results. For all parameters there Background. Exposure to a whiplash Brockhow T, Dillner A, Franke A, was a significant improvement versus injury implies a risk for development of Resch KL. Analgesic effectiveness baseline in both groups 2 weeks and 2 chronic disability and handicap, with of subcutaneous carbon-dioxide months following treatment, but no sig- reported frequencies ranging from 0% insufflations as an adjunct treat- nificant difference between the two to 50% in follow-up studies. The exact ment in patients with non-specific treatment groups. risk for development of chronic whip- neck or low back pain. A pragmatic, Conclusions.We conclude from lash syndrome is not known. open, randomized controlled trial. these results that needle placement in Objective. To prospectively deter- Comp Ther Med 2001; 9: 68-76. the area of the affected hip is associ- mine the sensitivity and specificity of Objectives. To evaluate the analge- ated with improvement in the symp- five possible predictors for handicap sic effectiveness of subcutaneous toms of osteoarthritis. It appears to be following a whiplash injury. carbon dioxide insufflations in addition less important to follow the rules of Methods. In a 1-year prospective to standard physical treatment in pa- traditional acupuncture techniques. study of persons with acute whiplash tients with non-specific neck or low injury (n = 141) and control subjects back pain. who had acute ankle distortion (n = Design. A pragmatic, randomized KNEE 40), pain intensity, number of controlled trial. Setting: Rehabilitation Matsui N, Kobayashi M. Application nonpainful neurologic complaints, cer- hospital inpatients. Interventions: Pa- of MR imaging for internal derange- vical mobility, workload during exten- tients received either subcutaneous ment of the knee. Seminars in sion and flexion of the neck, and results carbon dioxide insufflations (10 treat- Musculoskel Radiol 2001; 5(2): 139- of psychometric assessment were re- ments) and standard physical treat- 41. corded. The consecutively sampled ment or standard physical treatment injured persons were assessed with only. Outcome measures: Affective 86

87 Australasian Musculoskeletal Medicine November 2001 Journal Abstracts pain perception (42-point scale), sen- to evaluate differences in rating ac- back pain that address these issues sory pain perception (30-point scale), cording to age, gender, clinical his- are suggested. pain intensity (100 mm visual analogue tory, and clinical appropriateness of scale). the examination, as determined by Results. Between-groups differ- comparing information in the referral Gottschalk A, Smith DS. New Con- ences were -2.2 [95% CI -5.2; +0.9] form with Norwegian (NR) and British cepts in Acute Pain Therapy: Pre- (affective pain perception), -1.2 [-3, 0; (BR) recommendations for use of ra- emptive Analgesia. Am Fam Physi- + 0.7] (sensory pain perception), and diography. Each of the 99 patients also cian 2001; 63: 1979-86. -6.5 [-14; + 1.0] (pain intensity) re- underwent a semistructured interview spectively in favour of subcutaneous that was based on questions about Pain, which is often inadequately carbon dioxide insufflations. importance, usefulness, and reasons treated, accompanies the more than Conclusions. Subcutaneous carbon for the radiography referral. Answers 23 million surgical procedures per- dioxide insufflations do not seem to be were categorised and described using formed each year and may persist a worthwhile adjunct in the given set- a qualitative method (template analy- long after tissue heals. Pre-emptive ting of inpatient rehabilitation. Trials in sis). analgesia, an evolving clinical con- a monotherapeutic setting, which aim Results. Seventy-two percent (68 of cept, involves the introduction of an more at the efficacy of subcutaneous 93) of patients rated radiography as analgesic regimen before the onset of carbon dioxide insufflations, might help very important. The proportion was noxious stimuli, with the goal of pre- to solve this issue. higher for men than women (85% vs venting sensitisation of the nervous 65%, p = 0.04), higher for those with system to subsequent stimuli that could worsening than those with improving/ amplify pain. Surgery offers the most Espeland A, Baerheim A, Albrektsen unchanged symptoms worsen (86% promising setting for pre-emptive anal- G, et al. Patients views on impor- vs 65%, p = 0.03), and higher for gesia because the timing of noxious tance and usefulness of plain radi- inappropriately than appropriately re- stimuli is known. When adequate drug ography for low back pain. Spine ferred patients (NR: 76% vs 61%, p = doses are administered to appropri- 2001; 26(12): 1356-63. 0.17; BR: 81% vs 56%, p = 0.01). The ately selected patients before surgery, qualitative analysis showed that the intravenous opiates, local anaesthetic Study Design. Quantitative and quali- patients related their views on the im- infiltration, nerve block, subarachnoid tative cross-sectional interview study. portance and usefulness of receiving block and epidural block offer benefits Objectives. To investigate how pa- radiography to seven different issues: that can be observed as long as one tients who are referred for plain radi- symptoms and clinical history, infor- year after surgery. The most effective ography because of low back pain mation and advice (especially from pre-emptiveanalgesic regimens are perceive the importance and useful- health care providers), need for emo- those that are capable of limiting ness of the examination. tional support from the physician, need sensitisation of the nervous system Summary of Background Data. Up for certainty and reassurance, need throughout the entire peri-operative to 50% of plain radiography examina- for symptom explanation and diagno- period. tions for low back pain may be unnec- sis, reliability of radiography com- essary based on clinical criteria. How- pared with clinical evaluation, and ex- ever, many patients have great confi- pected practical consequences of the Leclaire R, Fortin L, Lambert R, et dence in these examinations. A further radiological examination. al. Radiofrequency Facet Joint exploration of the patients views may Conclusions. The finding that inap- Denervation in the Treatment of indicate how their needs can be met propriately referred patients tended to Low Back Pain: A Placebo-Control- without unnecessary use of radiogra- rate their radiography referral as more led Clinical Trial to Assess Efficacy. phy. important than appropriately referred Spine 2001; 26: 1411-17. Methods. Ninety-nine patients (65 patients indicates that the patients women, 3 men) 14-91 years of age view may be a substantial barrier to Study Design. A prospective dou- who were referred from Norwegian appropriate use of radiography. The ble-blind randomised controlled trial general practitioners for plain radiog- study identified seven issues underly- was performed. raphy of the lumbo-sacral spine were ing the patients views on importance Objective. To assess the efficacy of asked to rate the examination as and usefulness of receiving radiogra- percutaneous radiofrequency articu- slightly/fairly or very important (93 re- phy. Strategies to prevent unneces- lar facet denervation for low back pain. sponded). Chi-squared tests were used sary use of plain radiography for low 87

88 Australasian Musculoskeletal Medicine November 2001 Journal Abstracts Summary of Background Data. Comment. It is patently obvious that Uncontrolled observational studies in the authors of this article and Dr Deyo patients with low back pain have re- (Point of View) have not read the ported some benefits from the use of AFMM guidelines on lumbar medial facet joint radiofrequency denervation. branch blocks. If they had they would Because the efficacy of percutaneous have soon realised that this study was radiofrequency had not been clearly a waste of time due to the use of intra- shown in previous studies, a articular facet injections to predict re- randomized controlled trial was con- sponse to radiofrequecy ablation (RFA) ducted to assess the efficacy of the of the medial branch. The conclusions technique for improving functional dis- that the authors and Deyo make from abilities and reducing pain. the study are thus erroneous and just Methods. For this study, 70 patients perpetuate misinformation about this with low back pain lasting of more than useful (in the right hands) proceedure. 3 months duration and a good re- These authors need to read Dreyfuss sponse after intraarticular facet injec- article on radiofrequency denervation tions under fluoroscopy were assigned to understand correct methodology, randomly to receive percutaneous i.e., using controlled medial branch radiofrequency articular facet blocks before considering RFA. - Dr denervation under fluoroscopic guid- Scott Masters ance or the same procedure without effective denervation (sham therapy). The primary outcomes were functional disabilities, as assessed by the Oswestry and Roland-Morris scales, and pain indicated on a visual analog scale. Secondary outcomes included spinal mobility and strength. Results. At 4 weeks, the Roland- Morris score had improved by a mean of 8.4% in the neurotomy group and 2.2% in the placebo group, showing a treatment effect of 6.2% (P = 0.05). At 4 weeks, no significant treatment ef- fect was reflected in the Oswestry score (0.6% change) or the visual analog pain score (4.2% change). At 12 weeks, neither functional disability, as assessed by the Roland-Morris scale (2.6% change) and Oswestry scale (1.9% change), nor the pain level, as assessed by the visual analog scale (- 7.6% change), showed any treatment effect. Conclusions. Although radiofreq- uency facet joint denervation may pro- vide some short-term improvement in functional disability among patients with chronic low back pain, the effi- cacy of this treatment has not been established. 88

89 Australasian Musculoskeletal Medicine November 2001 FIMM Update: Thirteenth Triennial International Congress, Chicago, USA Dr Ron Palmer, Vice-President, FIMM T he thirteenth International Michael Kuchera said, This congress no objection to this overall approach. Congress of the Federation is about you and your patients. Inte- Simply, treat the patient as a unit rather of Manual/Musculoskeletal grative Manual Medicine is about shar- than look at only a single presenting Medicine was held in Chicago, USA, ing the safe and effective application of condition. On this theme, I was most on July 23-27, 2001. The title for the manual medicine techniques integrated impressed by a workshop given by conference was Integrative Manual according to the most current evi- Robert Irvin and Michael Kuchera on Medicine. The meeting was held at the dence base and clinical experience of Postural Balance Strategies using Chicago Mariott Downtown Hotel, a physicians dedicated to maximizing Orthotics. This workshop approached massive structure of 45 levels. The health and the function of each indi- many of the anatomical changes that congress was sponsored by the vidual. will occur when there is an overall body Kirkville College of Osteopathic Medi- The format of the conference was imbalance produced by foot changes. cine, the University of Wisconsin Med- fundamentally formal lectures in all the It was singularly the most constructive ical School in cooperation with the Am- morning sessions and practical work- and informative lecture I have attended erican Academy of Osteopathy (AAO) shops in the afternoon periods. The on the use and function of orthotic and the American Association of Ortho- afternoon workshops were of about devices. Bob Irvine will have a textbook paedic Medicine (AAOM). Congress two hours duration and were repeated. published on this subject next year. If chairman was Dr Michael Kuchera. There were also pre- as well as post- the book is as good as his presentation The International Federation of conference workshops. Lecture and then I fully recommend it. Manual/Musculoskeletal Medicine workshop duties were evenly divided At the general assembly (AGM) it (FIMM) is an organisation comprising between MDs and DOs (doctors of was agreed that the next triennial con- 26 member nations which have a com- osteopathic medicine). Australian mus- gress should be held at Bratislava, mon goal in advancing scientific and culoskeletal medicine was well repre- Slovakia, in 2004. The next annual educational awareness and training. sented with contributions by Norm general assembly will be held in Kuopio, Via select multinational committees, it Broadhurst, Phillip Watson, Michael Finland, on 6-7 September 2002. All aims to establish an International Col- Yelland, and myself. There were nine executive positions will be decided at legium for Musculoskeletal Medicine. Australians at the conference, includ- this meeting. The Finnish Association While most aims of the member na- ing AAMM Past President Dr Conrad of Manual/Musculoskeletal Medicine tional organisations are reasonably Winer. will be responsible for staging the event. uniform, there are some philosophical The standard of paper presentation Kuopio is a city 400 km north of Hel- and education differences that sepa- was somewhat mixed. There were many sinki, with a population of 90,000. It is rate a small number of the member excellent papers and unfortunately situated close to the Russian border countries. One of the aims of FIMM several that were not up to the stand- and can be reached by plane, train, or international meetings is to work closely ard that should have been expected bus from Helsinki. The city has a medical together and bridge the current gulfs. from such an illustrious presentation school on the shores of Lake Kallavesi, The Chicago congress was most suc- group. All official FIMM presenters one of hundreds of lakes located in the cessful in narrowing many of these performed well and the scientific surrounding district. In conjunction with ideological differences. Attendance at input from Stefan Blomberg and the general assembly, the education the congress was similar in size to the Jacob Patijn was excellent in fact, and scientific committees will meet prior last triennial congress held at Surfers a highlight of the conference. It was to the conference. Paradise, Australia, in 1998. my opinion that the standard of re- It was passed at the recent AGM that Advances in technology, both medi- search work is advancing well within the work of the education and scientific cal and communication, together with our group and the evidence-based committees should continue, as the a shrinking global base, lend support to approach to patient management is standard being achieved by them is of the concept of international coopera- also progressing in a favourable for- a very high quality. It is hoped that from tion and a single organisational body to ward direction. There are still some the work being undertaken by these overview the advance of musculoskel- differences in management between two committees that a teaching pro- etal medicine. This international envi- MDs and DOs and, although the differ- gram will develop. FIMM sees the im- ronment of cooperation is conducive ences were obvious, there does ap- portance of lifting the standard of prac- to expanding the evidence base for this pear to be a narrowing of the different titioner knowledge and patient treat- aspect of medicine and will serve to philosophies. The total patient ap- ment techniques before the establish- raise the standards of the basic skill proach was emphasised by the osteo- ment of an International Collegium. At core and ultimately patient care. As pathic clinicians and personally I have present the standards are not uniform 89

90 Australasian Musculoskeletal Medicine November 2001 FIMM Update in all the 26 member countries. Aus- next scientific committee meeting will suggestions regarding the website tralia has representation on both com- be held in Prague at the Charles Uni- please feel free to contact me via by mittees. Professor Norm Broadhurst versity in early May 2002. email address: has replaced Dr Phillip Watson after The FIMM website is again up and [email protected] his retirement from the education com- running. The website was initially de- mittee and I am the representative on veloped in Queensland and, following Norm Broadhurst and I are happy to the scientific committee. These com- my accident, was taken over by the convey any thoughts or queries to the mittees meet once a year and have a English. It has been modified and has respective committees if you care to continuous dialogue through the a new address: www.fimm-online.org. contact us. The strength of any organi- Internet and email connections. The If there are any queries, questions or sation is only as strong as its collective membership. A Research Perspective on the FIMM Congress Dr Michael Yelland R eflecting on my time in Chi tation by Brian Degenhardt et al on the back pain. This wa published in the cago at the FIMM congress, interexaminer reliability of osteopathic New England Journal of Medicine in I would endorse many of palpatory evaluation of the lumbar 1999, despite some significant flaws in Ron Palmers comments above. In spine. This began by rejecting some the collection and analysis of data. particular, FIMM as an organization totally unreliable signs and going on to Robert Kappler, the studys treating seems to be moving towards an em- investigate the levels of reliability that physician, presented the results, but phasis on the evidence base for can be achieved by training examiners the best summary was by a Chicago manual/musculoskeletal medicine, and in the potentially reliable signs. I was reporter, who proclaimed that it showed to a more structured and uniform teach- told that this research was actually that osteopathic manipulative care was ing program for musculoskeletal medi- influencing the content of the curricu- just as effective as standard care. An cine throughout the world. At the same lum at osteopathic medical schools. intention to treat analysis may have time it provides a forum for teachers There were some interesting pres- shown it to be superior but this was not and practitioners of the large number entations on the effect of osteopathic done. On the positive side, the study of systems of diagnosis and treatment manipulative treatment of both visceral did demonstrate that patients treated which exist within musculoskeletal and musculoskeletal conditions. One with manipulation had lower usage of medicine. These systems range from study showed that, while it had no medication and physical therapy and the traditional biomedical ones, like effect on the serological response to had an improvement in nearly all of orthopaedics, to others which are the influenza vaccine in the frail eld- their physical findings. However sug- strong on mystique and weak on sci- erly, it was associated with a lower gestions of recruitment bias into the ence, such as neural therapy. From incidence of respiratory and urinary osteopathic group and observer bias my perspective as someone inter- tract infections and a reduced usage in data collection both cast doubt on the ested in research, this offers a fertile of antibiotics. Another study showed validity of these findings. ground for research into claims that it that osteopathic manipulation follow- The osteopathic manipulation study works in my hands. And there was ing knee or hip arthroplasty actually was easily overshadowed both in qual- evidence at the FIMM congress that increased the length of hospital stay ity and positive results by the work this research is happening. and reduced the rehabilitation effi- presented by the next speaker, Stefan The congress program, having been ciency. In contrast, a small randomized Blomberg, from Sweden. He presented organised by the American Osteo- controlled trial on its effect on the results of his three RCTs on manual pathic Medicine Association, natu- osteoarthritis of the knee showed it to therapy and steroid injections for acute rally had a strong osteopathic flavour. be superior to control treatment for and chronic low back pain, showing It was encouraging to see some genu- most outcome measures. The largest them to be consistently superior to ine attempts at critical evaluation of the and most publicised study was a com- standard care for a wide range of osteopathic approach. For example, parison of osteopathic spinal manipu- outcomes. The quality of the studies there was a very good poster presen- lation with standard care for acute low was easily the highest at the confer- 90

91 Australasian Musculoskeletal Medicine November 2001 FIMM Update ence quite inspirational to other re- the concept of tensegrity or tension ing people to meet from around the searchers. It would be good to get him integrity which addresses the inability world. Finally, some of the State of the out to Australia to teach us his evi- of conventional biomechanical models Art lectures on various disciplines within dence-based algorithm for low back to explain how muscles move joints with musculoskeletal medicine were so su- pain treatment. such short lever arms without fractur- perficial and broad ranging as to be of For prolotherapists, like myself, there ing bones. He views the musculoskel- little use to anyone. Those dealing with was quite a lot on offer, even though the etal system as a complex system of specific conditions, such as carpal tun- preconference weekend workshop was trusses with tension and compression nel syndrome, were much more useful. cancelled due to lack of registrations. elements spreading the load and con- Would I go to the next congress in Tom Dorman spoke eloquently on the serving energy. Bratislava in 2004 yes I would cer- history, theory, and practice of prolo- Despite the excellent venue, there tainly like to. I do hope that is long therapy and the trial evidence for its were a few disappointments. There enough for the Ozzie dollar to drag efficacy. Bjrn Eek talked about the was quite poor attendance at some of itself out of the doldrums. Chicago was indications and limitations of prolo- the research sessions, although they a lot of fun but very expensive for therapy, including his research into did have to compete with concurrent Australians. At the end of the congress intradiscal prolotherapy. This was com- practical workshops. Another reason I popped into an art shop and found a plemented by an excellent short work- was the low number of registrations painting for sale that was going for shop given by Jeff Patterson and Tom overall. It was surprising that, in a big roughly what our house and land are Ravin with a very good video on city like Chicago, the congress at- worth. Perhaps Chicagos gangsters technique. Perhaps the most fascinat- tracted no more registrants than we did from last century have just donned ing presentation was given by Steven here at FIMM in the Antipodes in 1998. suits in this one and moved to the other Levin from Virginia. He talked about Still, there was no shortage of interest- side of the cash registers! Comments about the Chicago Triennial Conference of FIMM Professor Norm Broadhurst I share the impressions of those of conferences when they were held in managed and how can we arrived at a Ron Palmer and Michael Yelland Europe a decade or so ago. Similarly, consensus - or do we need to? concerning the recent FIMM. Con- workshops in Australia a few years ago It is without any fear of contradiction ference and wish to congratulate the attracted scores of practitioners but that we in Australasia are making every organisers on a well-organised pro- now such workshops are either poorly effort to teach and implement muscu- gram. I felt very privileged to be invited attended or not programmed at all. loskeletal medicine from an evidence to present a workshop on pelvic pain While the plenary sessions were a base. This is reflected in the post- and in addition to have a free paper mixed bag I felt that the workshops graduate diploma programs and the accepted on the morphology of the provided an excellent means to see final report of the National Muscu- piriformis muscle. I can say my so- how the numerous modalities were loskeletal Medicine Initiative. Thus we journ in Chicago was both enjoyable used to treat similar dysfunctions with are in the position to support and and memorable and I look forward to equally positive outcomes according contribute to the proceedings of the going to Bratislava in three years time. to the various presenters. These educational committee of FIMM, which It was regrettable to arrive and see modalities included Pain Free Maignes is chaired by Glen Rasmussen. This about 200 registrants when 10 times Method, Treatment of Still, Myofascial committee is compiling a database on that number was hoped for. Lack of Trigger Points, Treatment of Suther- what is taught in this field throughout support for this conference especially land, Facilitated Positional Release, the world. This database is assessed by the host nation, and the one on the Myofascial Release, Counter strain of against the evidence base, which should Gold Coast three years ago, raises the Jones, Muscle Imaging Techniques, culminate in a few years in the body of question whether we are losing the Zones of Sell, etc. This then begs the knowledge and practice of muscu- plot. I was informed by some of the question as to what is reliable and valid loskeletal medicine that most certainly older members that thousands attended in the way musculoskeletal pain is should lead to specialist recognition. 91

92 Australasian Musculoskeletal Medicine November 2001 Musculoskeletal Medicine Educational Activities MASTERS, DIPLOMA AND CERTIFICATE COURSES IN MUSCULOSKELETAL MEDICINE FLINDERS UNIVERSITY DIPLOMA/CERTIFICATE IN MUSCULOSKELETAL MEDICINE DATE TITLE/KEY VENUE PROVIDER CONTACT CME POINTS RESOURCE PERSON 18-24/11/01 Module one - Flinders Flinders A/Prof Norm 50 per module Anatomy, Medical University, Broadhurst Physiology and Centre, South Ph 08-82951890 Biomechanics. Adelaide Australia 23/2/02 Module two - Flinders Flinders A/Prof Norm 50 per module 3/3/02 Clinical Skills Medical University, Broadhurst Centre, South Ph 08-82951890 Adelaide Australia UNIVERSITY OF NEWCASTLE MASTERS IN PAIN MEDICINE DATE TITLE/KEY VENUE PROVIDER CONTACT CME POINTS RESOURCE PERSON 2002 Masters in Pain Internet University Prof Nikolai N/A Medicine of Newcastle Bogduk Ph +61-2-49236172 Fax +61-2-49236103 [email protected] newcastle.edu.au 92

93 Australasian Musculoskeletal Medicine November 2001 Musculoskeletal Medicine Educational Activities UNIVERSITY OF OTAGO DIPLOMA/CERTIFICATE IN MUSCULOSKELETAL MEDICINE DATE TITLE/KEY VENUE PROVIDER CONTACT CME POINTS RESOURCE PERSON 24/2/02- MSME 701 On campus, University of Otago V. McGroggan On 2/3/02 Part 1 Clinical Australian venue Ph. +64 3 364 1086 application Diagnosis (Aust.) in Queensland Fax +64 3 364 0909 to be advised Email: veronica. 16-24 Part 1- Clinical NZ venue - As above [email protected] 50 points* /3/02 Diagnosis Christchurch chmeds.ac.nz (New Zealand) School of or Medicine & Geoff Harding Health Sciences Ph +61-7-32695522 29/7/02 - Part 2- Clinical Christchurch Fax +61-7-32696407 (*total Pt1 & 2) 2/8/02 Diagnosis Email: geoffharding (New Zealand) @uq.net.au website - www. 9/02 Part 2- Clinical Queensland chmeds.ac.nz/ Diagnosis (Aust.) go/dept-orthop 14/2/02 - MSME 704 Fortnightly As above Same contacts NZ on 6/02 Pain teleconferences as above application on Tuesdays Aust.-50 points 14/2/02 - MSME 708 Fortnightly As above Same contacts NZ on 6/02 Pain teleconferences as above application management on Tuesdays Aust.-50 points 21/2/02 - MSME 709 On campus As above Same contacts NZ on 3/3/02 Clinical Aust. venue as above application Therapeutics in Qld to be Aust.-50 points Australia advised 16-22 New Zealand NZ venue As above Same contacts NZ on /03/02 Christchurch as above application School of Aust.-50 points Medicine & Health Sciences 21/2/02 - MSME 705 Fortnightly As above Same contacts NZ on 6/03 Regional teleconferences as above application Disorders - Spine on Tuesdays Aust.-50 points and MSME 706 - Regional Disorders - Limbs 7-10 MSME 707 Fortnightly As above Same contacts NZ on /02 Musculoskeletal teleconferences as above application Rehabilitation on Tuesdays Aust.-50 points 7-10 MSME 710 Fortnightly As above Same contacts NZ on /02 Recreational teleconferences as above application and Sports on Tuesdays Aust.-50 points Injuries 93

94 Musculoskeletal Medicine Educational Activities OTHER MUSCULOSKELETAL MEDICINE EDUCATIONAL ACTIVITIES DATE TITLE/KEY VENUE PROVIDER CONTACT CME RESOURCE POINTS PERSON 24-26 Beyond the Horn Sydney Australian Pain DC Conferences To be /3/02 - Australian Convention Society Ph 02-94396744 announced Pain Society Centre Fax 02-94392504 Ann. Scientific Email [email protected] Meeting Website:www.apsoc.org.au Weekend Prolotherapy Fullarton, Australasian Dr Margaret Taylor Nil March/ Workshop Adelaide, SA Prolotherapy Ph: 61-8-8338 2899 April 02 Association Fax: 61-8-8338 2911 Email: [email protected] 7-10 Rehabilitation: Sheraton Australasian DC Conferences To be /5/02 A Global Persp- Hotel, Faculty of Ph 02-94396744 announced ective Ann. Brisbane Rehabilitation Fax 02-94392504 Scientific Meet- Medicine Email [email protected] ing of Australas. dcconferences.com.au Faculty of Rehabilitation Medicine (Preconference course:State of the Art Review of Back Pain on 7/5/02) 18-20 A Pain in the Melbourne AAMM Vic Wilk To be /10/02 Butt: Groin, Hip venue to be Ph +61-3-95967211 announced and Pelvic announced Fax +61-3-95967871 Pain. Annual Email: [email protected] Scientific smart.net.au Meeting of the AAMM and AFMM 15-19 Pain in Child- Sydney Paediatric DC Conferences To be /6/03 hood: The Big Convention Pain Medicine Ph 02-94396744 announced Questions Centre Unit, Sydney Fax 02-94392504 International Childrens Email [email protected] Symposium Hospital dcconferences.com.au on Paediatric Website: Pain www.sydneykidz.net

95 AUSTRALIAN ASSOCIATION OF MUSCULOSKELETAL MEDICINE (AAMM) MANAGEMENT OF LATERAL ELBOW PAIN (TENNIS ELBOW) (Information for Patients) What is lateral elbow pain? Lateral elbow pain refers to pain felt on the outside of the elbow. It is a common complaint, usually resulting from repetitive use or sustained contraction of the forearm muscles. Many of the muscles that move the wrist and fingers are found on the lateral side of the elbow where they attach to bone. Lateral elbow pain is usually due to strain in one or more of these muscles close to their bony attachment. Lateral elbow pain has been given many different names in the past. These include tennis elbow, lateral epicondylitis, and extensor tendonosis. What are the symptoms? Lateral elbow pain is usually deep, dull, and aching. This pain can spread down the forearm to the hand, and/or up the arm to the shoulder. Pain can be present at rest but more commonly is brought on or aggravated by activity, especially lifting, twisting and grasping. What tests are useful? Lateral elbow pain is diagnosed on the basis of the medical history and physical examination. It cannot be diagnosed by any blood test or on x-ray. What is the treatment? The goals of treatment are to relieve pain and allow resumption of normal activities with as little discomfort as possible. Following are some simple measures that will help you achieve these goals. 1. Avoidance of aggravating activities is the most important aspect of treatment. This includes work, domestic, and sport activities. The avoidance may not have to be complete. A decrease in frequency or rate of the activity may be sufficient. Learning to modify the way some activities are performed may also be helpful. In general, performing activities with the palm up will be less stressful than performing them palm down. 2. Heat and ice are good for controlling pain. Heat may be applied on a regular basis. Heat or ice may be applied to the outside of the elbow before activity to reduce discomfort. Ice is best used to relieve pain after an aggravating activity. 3. Painkillers are useful. Your doctor will advise you about the best and safest ones to use. Anti-inflammatories have not been shown to have any extra benefit over other analgesics 4. Stretching and strengthening exercises for the forearm muscles are often helpful. A specific exercise program can be devised by a musculoskeletal physician to maximise your functional recovery. 5. Massage of the painful muscle(s) is often helpful. 6. A counter-force brace is a tight non-flexible strap worn just below the elbow. It is believed to relieve the strain on the injured muscle(s) at the elbow. It is particularly helpful when used whilst performing aggravating activities. 7. An injection of steroidal anti-inflammatory with local anaesthetic is the most effective treatment for lateral elbow pain. This is not very painful and is well tolerated. Side effects can occur, but are rare. This is your best option if the above suggestions have not helped. For best results it is suggested to do strengthening and stretching exercises in the weeks following the injection. 8. Total rest with your arm in a sling is best avoided. It can be used for very severe pain, but even then only for a very short period. 9. Extracorporeal shock wave therapy is a promising new treatment for more chronic cases. The above information should allow you to understand the nature of your condition and how to manage it. The information provided is based on the currently available scientific evidence. You will notice that this approach does not involve the use of expensive tests or gadgets, and does not involve the patient attending for treatment several times a week. Instead, you are given the information and thus can help develop the management plan. You are encouraged to play a proactive role in the management of your problem. Active patient participation in their treatment is known to improve results. Musculoskeletal physicians are doctors who have completed extra postgraduate training in the management of a wide range of musculoskeletal conditions including lateral elbow pain. Our aim is full restoration to a functional and healthy state as quickly as possible.

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