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This week in the BMJ: Managing low back pain BMJ 2006; 332: 0-a [Full text]

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The benefits of spinal stenosis surgery

Paul L Thorpe   (24 June 2006)

Evidence-based low back care??

Ronald Donelson   (14 July 2006)

Are some researchers biased?

Robin McKenzie, New Zealand   (14 July 2006)

Missing evidence

Helen Anne Clare   (16 July 2006)

Clinicians' frustration

Andrew J Holdom, Annette Bishop   (21 July 2006)

The benefits of spinal stenosis surgery 24 June 2006
Paul L Thorpe, Consultant Spinal Surgeon Somerset Spinal Surgery Service Musgrove Park Hospital TA1 5DA Send response to journal: Re: The benefits of spinal stenosis surgery	Dear Sir 23.06.06 Koes, van Tulder, and Thomas(1) present an interesting review of lower back pain. However, they emphasise multidisciplinary care only in the context of conservative care. There is a clear agenda in UK healthcare to emphasise primary care management for common conditions such as back pain. This is partly at least to try and control costs of investigation and intervention associated with secondary or tertiary referral. However, with respect to lower back pain, sciatica and spinal claudication, this has often resulted in an overly jaded presentation of the possible benefits of spinal surgery – sometimes based on an unrealistic presentation to patients of outcomes and complication rates of spinal surgery by primary care health professionals who have had little training in the assessment and treatment of musculoskeletal disease, and may have no ongoing access to MRI or links to spinal surgery services. The authors go some way to reinforce that misconception by a flawed statement on spinal stenosis surgery. There is clear evidence from well constructed randomised controlled and prospective observational studies that in spinal stenosis, decompressive surgery can confer safe, rapid and early symptomatic relief for patients suffering from sciatic and claudicant symptoms(2,3). The authors may have wished to imply that decompressive surgery is not helpful for lower back pain – a statement that the spinal surgery fraternity would generally support – but they do not make this clear, and dismiss surgery, proven to be often helpful, in a single sentence. The important principle in the management of patients with lower back pain and leg pain is that although spinal surgery probably only has something to offer to 8-10% of patients, that is a small percentage of a very large number of patients – and it means that primary care organisations must ensure competent and close collaboration with a spinal surgery service if they are to offer their patients a truly multidisciplinary approach. Yours faithfully, Mr Paul L P J Thorpe MB ChB FRCSEd(Orth) Consultant Spinal Surgeon Somerset Spinal Surgery Service Level 1 Queens Building Musgrove Park Hospital Taunton TA1 5DA 1. Koes BS, van Tulder MW, Thomas S, Diagnosis & treatment of low back pain BMJ 2006;332:1430-4 2. Amundsen T, Weber H et al, Lumbar Spinal Stenosis: Conservative or Surgical Management – a prospective 10 year study Spine 2000;25(11):1424- 1436 3. Long-term outcomes of surgical & nonsurgical management of Lumbar Spinal Stenosis: 8-10 year results from the Maine Lumbar Spine Study Spine 2005;30(8):936-943 Competing interests: None declared
Evidence-based low back care?? 14 July 2006
Ronald Donelson, President Self Care First, LLC, 13 Gibson Road, Hanover, NH, 03755, U.S.A. Send response to journal: Re: Evidence-based low back care??	I would like to respond to the recent clinical review article by Koes, van Tulder, and Thomas that addressed the diagnosis and treatment of low back pain (Koes B, van Tulder M, Thomas S. Clinical review: diagnosis and treatment of low back pain. British Medical Journal 2006; 332:1430-4). Their statement that “at present no reliable and valid classification system exists for most cases of non-specific low back pain” is quite problematic. While compatible with the position taken by most clinical guidelines, this position nevertheless continues to ignore the growing list of studies that strongly establish the interexaminer reliability of identifying the clinical findings of the centralization pain response and directional preference, that single direction of repeated end-range lumbar bending that centralizes and/or abolishes so many patients’ pain.2,8,11,12,16,18,22,24 The presence or absence of these two findings enable classification of patients into distinct pain response subgroups that are at the heart of the Mechanical Diagnosis and Therapy (MDT) paradigm, better known to many as the McKenzie methods of low back care.15 Overlooked as well is a second lengthy list of studies providing substantial preliminary validation of these same two clinical findings and subgroups as predictors of good and excellent outcomes, especially when centralizers are treated with exercises and posture strategies that match patients’ directional preference.3,6,10,13,17,19,21,22 Most important are two randomized clinical trials that further validate centralization and directional preference.1,14 Long et al reported that 74% of those presenting with acute, subacute and chronic back pain were found during their baseline assessment to have a directional preference.14 Only this large subgroup was then randomized. Ninety-five percent of those assigned to exercises that directionally matched their directional preference improved or fully recovered in just two weeks, with no one worsening or withdrawing. This is in remarkable contrast to the outcomes of those subjects (also with a baseline directional preference) randomized to guideline-consistent care (assurance of recovery and advice to remain active) and non-specific exercises. Only 42% of this latter group improved or recovered, 15% actually worsened, and 33% withdrew early due to little or no improvement. It was the ethics committee that limited the study to only two weeks based on their insight and concern about treating patients with exercises that did not match their directional preference. Even they understood the validity of directional preference in treatment selection. How comprehensive is this classification? A large number of studies report that most non-specific low back pain can be centralized and abolished using directional exercises (70-87% in acutes and up to 50% in chronics).3,5-7,10,13,14,17,19,21-23. The alternative and much smaller non-centralizing subgroup also has good evidence that non-centralization strongly predicts poor or non-recovery, apparently even more so than psychosocial factors when these two predictors have been compared head-to- head.21 This MDT classification is indeed quite comprehensive. So the statement that “no reliable and valid classification system exists for most cases of non-specific low back pain” resembles a consensus view rather than an evidence-based statement. This is quite disappointing coming from prominent guideline and systematic review experts whose familiarity with the low back literature would be expected to be far greater than this. These authors also repeat another familiar guideline conclusion that there is “strong evidence that specific back exercises are not effective,” perpetuating the conclusions of van Tulder et al’s 2000 systematic review of exercise.20 I wrote a similar letter-to-the-editor at that time for which there was no response from the authors.4 Persisting with this same view disregards the findings of the Brennan et al, and especially the Long et al randomized clinical trials. Both report that specific exercises, when matched to patients’ baseline subgrouping, bring superior, perhaps far superior, treatment outcomes.1,14 Despite these many oversights, it is encouraging that Koes et al at least recognized the Brennan et al study1 as a “promising development” that documents the value of matching treatment selections to validated subgroups determined by examining and classifying patients at baseline. It seems that Koes et al are unaware that, not only does this study directly contradict their position that specific exercises are not effective, but members of the “specific exercise” subgroup in this classification system are solely determined by patients’ baseline clinical findings of centralization and directional preference. Finally, nearly all clinical guidelines, as well as this article by Koes et al, perpetuate the perceived importance of psychosocial factors as obstacles to recovery despite acknowledging the absence of any evidence that addressing these factors improves outcomes. Reviewing one such negative study at some length9 seemed odd in light of the authors’ failure to recognize so many positive reliability, prognostic, and randomized clinical trials targeting centralization and directional preference. So the fundamental question becomes whether this clinical review article, and most low back pain clinical guidelines for that matter, are as evidence-based as their authors portray them to be. Consensus-based recommendations can be helpful in the absence of evidence, however they become quite problematic, even misleading, when the consensus ignores existing relevant evidence. I apologize for my lengthy list of references yet, given the topic, this seems justified and will hopefully be helpful to readers. Ron Donelson, MD, MS References 1. Brennan G, Fritz J, Hunter S, et al. Identifying subgroups of patients with acute/subacute “nonspecific” low back pain. Results of a randomized clinical trial. Spine 2006;31:623-31. 2. Clare H, Adams R, Maher C. Reliability of the McKenzie spinal pain classification using patient assessment forms. Physiotherapy 2004;90:114-9. 3. Delitto A, Cibulka M, Erhard R, et al. Evidence for an extension- mobilization category in acute low back syndrome: a prescriptive validation pilot study. Physical Therapy 1993;73:216-28. 4. Donelson R. Letter to the editor. Spine 2001;26:1827-9. 5. Donelson R, Aprill C, Medcalf R, et al. A prospective study of centralization of lumbar and referred pain: A predictor of symptomatic discs and anular competence. Spine 1997;22:1115-22. 6. Donelson R, Silva G, Murphy K. The centralization phenomenon: its usefulness in evaluating and treating referred pain. Spine 1990;15:211-13. 7. Erhard R, Delitto A, Cibulka M. Relative effectiveness of an extension program and a combined program of manipulation and flexion and extension exercises in patients with acute low back syndrome. Physical Therapy 1994;74:1093-100. 8. Fritz J, Delitto A, Vignovic M, et al. Interrater reliability of judgments of the centralization phenomenon and status change during movement testing in patients with low back pain. Archives of Physical Medicine and Rehabilitation 2000;81:57-61. 9. Jellema P, van der Windt D, van der Horst H, et al. Should treatment of (sub)acute low back pain be aimed at psychosocial prognostic factors? Cluster-randomised clinical trial in general practice. British Medical Journal 2005;331:84-90. 10. Karas R, McIntosh G, Hall H, et al. The relationship between non -organic signs and centralization of symptoms in the prediction of return to work for patients with low back pain. Physical Therapy 1997;77:354-60. 11. Kilby J, Stigant M, Roberts A. The reliability of back pain assessment by physiotherapists, using a "McKenzie algorithm". Physiotherapy 1990;76:579-83. 12. Kilpikoski S, Airaksinen O, Kankaanpää M, et al. Interexaminer reliability in low back pain assessment using the McKenzie method. Spine 2002;27:E207-14. 13. Long A. The centralization phenomenon: its usefulness as a predictor of outcome in conservative treatment of chronic low back pain. Spine 1995;20:2513-21. 14. Long A, Donelson R, Fung T. Does it matter which exercise? A randomized controlled trial of exercise for low back pain. Spine 2004;29:2593-602. 15. McKenzie R, May S. Mechanical Diagnosis and Therapy. Second ed. Waikanae, New Zealand: Spinal Publications New Zealand Ltd., 2003. 16. Razmjou H, Kramer J, Yamada R. Inter-tester reliability of the McKenzie evaluation of mechanical low back pain. Journal of Orthopedic & Sports Physical Therapy 2000;30:368-83. 17. Skytte L, May S, Petersen P. Centralization - its prognostic value in patients with referred symptoms and sciatica. Spine 2005;30:E(293 -9). 18. Spratt K, Lehrmann T, Weinstein J, et al. A new approach to the low back physical examination: behavioral assessment of mechanical signs. Spine 1990;15:96-102. 19. Sufka A, Hauger B, Trenary M, et al. Centralization of low back pain and perceived functional outcome. Journal of Orthopedics and Sports Physical Therapy 1998;27:205-12. 20. van Tulder M, Malmivaara A, Esmail R, et al. Exercise therapy for low back pain. Spine 2000;25:2784-96. 21. Werneke M, Hart DL. Centralization phenomenon as a prognostic factor for chronic low back pain and disability. Spine 2001;26:758-65. 22. Werneke M, Hart DL, Cook D. A descriptive study of the centralization phenomenon. A prospective analysis. Spine 1999;24:676-83. 23. Williams M, Hawley J, McKenzie R, et al. A comparison of the effects of two sitting postures on back and referred pain. Spine 1991;16:1185-91. 24. Wilson L, Hall H, McIntosh G, et al. Intertester reliability of a low back pain classification system. Spine 1999;24:248-54. Competing interests: None declared
Are some researchers biased? 14 July 2006
Robin McKenzie, President McKenzie Institute International Raumati Beach 5032, New Zealand Send response to journal: Re: Are some researchers biased?	The Editor, I would like to comment on the Clinical Review entitled “Diagnosis and Treatment of Low Back Pain” by Koes and van Tulder (BMJ 2006;332; 1430 -1434). These authors provide an overview of the current evidence relating to the diagnosis and treatment of low back pain. While there is nothing new in their paper to excite the average clinician, the authors continue to state that there is strong evidence that specific exercises have no benefit. To their credit they make the point that promising developments suggest that “identifying subgroups of patients more amenable to specific treatments,” is an important step forward. Indeed the International Forum on Low Back Pain in 19981 emphasised that identification of subgroups is seminal to better management of non-specific low back pain. Despite this recommendation however, little has been done since that time to identify systems that have that potential. The authors cite two studies, Brennan et al 2 and Childs et al3 that demonstrate superior outcomes following treatment matched to suit the patient’s symptomatic responses. Indeed, the two studies cited contain the key element of centralisation as described by McKenzie in 1981.13 The authors, for some reason, have chosen to ignore the much earlier system of classification commonly referred to as Mechanical Diagnosis and Therapy13 now in widespread use in over 35 countries. This simple, inexpensive and low-tech clinical assessment procedure consists of repeatedly moving the patient to lumbar end-range in loaded and unloaded positions and recording the resultant patterns of symptomatic responses. Directions of movement (usually extension) that cause symptoms to cease, reduce in intensity or change location towards the mid line (centralisation) are described as the patient’s mechanically determined directional preference. This enables an immediate (in some cases only a few minutes) and reliable determination of appropriate specific exercise and posture for each individual. Conversely, such patients, when moved in the opposite direction (usually flexion), will experience symptoms that appear, increase in intensity, or peripheralise. Studies have shown that clinically induced centralisation of pain based on patient’s directional preference is a reliable predictor of favourable outcome.5,6,11,12 Conversely, failure to achieve centralisation is now known to be indicative of poor outcome.16,17 Exercises specific to the patients’ directional preference can easily and commonly be identified. Koes and van Tulder continue to ignore this evidence for classification by symptomatic response. The findings of this assessment and the assignment of patients to their matching classification have demonstrated in multiple studies to have interexaminer reliability if the exam in conducted by properly trained clinicians.4,9,14 And in various ways, numerous cohort studies7,8,10,15-17 and one randomized clinical trial11 all demonstrate that specific exercises matched to the patients’ directional preference provide superior outcomes and consistently identify subgroups. A key randomized clinical trial demonstrated that a significant majority of patients improved when assigned the specific direction of exercise that matched their directional preference, whereas a majority of those who exercised in a direction opposite to their directional preference were either unimproved or were even worse. 11 With all this evidence published in the spinal research mainstream, it is difficult to understand how Koes and van Tulder continue to argue that specific back exercises are of no benefit. It is disappointing that twenty-five years after the first publication of the classification system that bears my name,13 the significance of centralisation and directional preference continues to be lost, misunderstood, or misapplied by those responsible for guiding the care and management of patients with low back pain as well as by those involved in back pain research. Robin McKenzie, CNZM, OBE, FNZSP (Hon), FCSP (Hon). Raumati Beach New Zealand. References 1. Borkan J, Koes B, Reis S, et al. A report from the second international forum for primary care research on low back pain: reexamining priorities. Spine 1998;23:1992-6. 2. Brennan G, Fritz J, Hunter S, et al. Identifying subgroups of patients with acute/subacute “nonspecific” low back pain. Results of a randomized clinical trial. Spine 2006;31:623-31. 3. Childs J, Fritz J, Flynn T, et al. A clinical prediction rule to identify patients with low back pain most likely to benefit from spinal manipulation: a validation study. Annals of Internal Medicine 2004;141:920 -8. 4. Clare H, Adams R, Maher C. Reliability of the McKenzie spinal pain classification using patient assessment forms. Physiotherapy 2004;90:114- 9. 5. Clare H, Adams R, Maher C. A systematic review of efficacy of McKenzie therapy for spinal pain. Australian Journal of Physiotherapy 2004;50:209- 16. 6. Cook C, Hegedus E, Ramey K. Physical therapy exercise intervention based on classification using the patent response method: a systematic review of the literature. JMPT 2005;13:152-62. 7. Donelson R, Silva G, Murphy K. The centralization phenomenon: its usefulness in evaluating and treating referred pain. Spine 1990;15:211-13. 8. Karas R, McIntosh G, Hall H, et al. The relationship between non- organic signs and centralization of symptoms in the prediction of return to work for patients with low back pain. Physical Therapy 1997;77:354-60. 9. Kilpikoski S, Airaksinen O, Kankaanpää M, et al. Interexaminer reliability in low back pain assessment using the McKenzie method. Spine 2002;27:E207-14. 10. Long A. The centralization phenomenon: its usefulness as a predictor of outcome in conservative treatment of chronic low back pain. Spine 1995;20:2513-21. 11. Long A, Donelson R, Fung T. Does it matter which exercise? A randomized controlled trial of exercise for low back pain. Spine 2004;29:2593-602. 12. Machado L, de Souza M, Ferreira P, et al. The McKenzie Method for Low Back Pain: A Systematic Review of the Literature With a Meta-Analysis Approach. Spine 2006;31:E254-62. 13. McKenzie R. The lumbar spine: mechanical diagnosis and therapyed. Waikanae, New Zealand: Spinal Publications, 1981. 14. Razmjou H, Kramer J, Yamada R. Inter-tester reliability of the McKenzie evaluation of mechanical low back pain. Journal of Orthopedic & Sports Physical Therapy 2000;30:368-83. 15. Sufka A, Hauger B, Trenary M, et al. Centralization of low back pain and perceived functional outcome. Journal of Orthopedics and Sports Physical Therapy 1998;27:205-12. 16. Werneke M, Hart DL. Centralization phenomenon as a prognostic factor for chronic low back pain and disability. Spine 2001;26:758-65. 17. Werneke M, Hart DL, Cook D. A descriptive study of the centralization phenomenon. A prospective analysis. Spine 1999;24:676-83. Competing interests: None declared
Missing evidence 16 July 2006
Helen Anne Clare, Director of Education McKenzie Institute 16 Ayres Road, St Ives, NSW 2075 Send response to journal: Re: Missing evidence	I would like to comment on the Clinical Review – Diagnosis and treatment of low back pain by Koes, van Tulder and Thomas (BMJ;332: 1430- 1434). I am in total agreement with their statement that “much research is focused on detecting relevant sub-groups of patients with low back pain with a different prognosis and susceptibility to specific treatments”. However they fail to acknowledge the research that has been done on the prognostic value of centralisation. In a systematic review of centralisation published in 2004 (Aina et al) (1) six studies were described that had investigated the prognostic value of centralisation (4,6,7,9,10,11) The conclusion of this review was that centralisation was consistently associated with better outcomes and that non-centralization was an important predictor of poor outcomes. Since this review a further study (George et al 2005) (5) has demonstrated that centralisation was a significant predictor of both pain and disability at 6 months post treatment whereas fear avoidance only predicted disability. The authors do describe the identification of subgroups of patients who are amenable to specific treatments as “promising developments”. They acknowledge studies by Brennan et al (2) and Childs et al (3) both of which demonstrate better outcomes when patients were provided with treatment that matched their classification than when unmatched treatment was provided. Again however they fail to acknowledge a key study, which supports the importance of sub-classification of patients before treatment. A important RCT (Long et al) (8) published in the same year as the Childs et al study,(3) demonstrated significantly better outcomes in patients who were treated with exercises appropriate for their classification based on directional preference than those patients who were treated with the exercise that was considered opposite to their directional preference. It seems inappropriate in a clinical review, which seeks to provide a summary of the current evidence for the diagnosis and treatment of low back pain that such key evidence is overlooked Helen Clare, PhD References 1. Aina A, May S, Clare H. The centralization phenomenon of spinal symptoms – a systematic review. Manual Therapy 2004; 9:134-143 2. Brennan G, Fritz J, Hunter S, et al. Identifying subgroups of patients with acute/subacute “nonspecific” low back pain. Results of a randomized clinical trial. Spine 2006;31:623-31. 3. Childs J, Fritz J, Flynn T, et al. A clinical prediction rule to identify patients with low back pain most likely to benefit from spinal manipulation: a validation study. Annals of Internal Medicine 2004;141:920 -8. 4. Donelson R, Silva G, Murphy K. The centralization phenomenon: its usefulness in evaluating and treating referred pain. Spine 1990;15:211-13. 5. George SZ, Bialosky JE, Donald DA. The centralization phenomenon and fear-avoidance beliefs as prognostic factors for acute low back pain: a preliminary investigation involving patients classified for specific exercise. J Orthopaedics Sports Physical Therapy 2005;35:580-588. 6. Karas R, McIntosh G, Hall H, et al. The relationship between non- organic signs and centralization of symptoms in the prediction of return to work for patients with low back pain. Physical Therapy 1997;77:354-60. 7. Long A. The centralization phenomenon: its usefulness as a predictor of outcome in conservative treatment of chronic low back pain. Spine 1995;20:2513-21. 8. Long A, Donelson R, Fung T. Does it matter which exercise? A randomized controlled trial of exercise for low back pain. Spine 2004;29:2593-602. 9. Sufka A, Hauger B, Trenary M, et al. Centralization of low back pain and perceived functional outcome. Journal of Orthopaedics and Sports Physical Therapy 1998;27:205-12. 10. Werneke M, Hart DL. Centralization phenomenon as a prognostic factor for chronic low back pain and disability. Spine 2001;26:758-65. 11. Werneke M, Hart DL, Cook D. A descriptive study of the centralization phenomenon. A prospective analysis. Spine 1999;24:676-83. Competing interests: None declared
Clinicians' frustration 21 July 2006
Andrew J Holdom, Physiotherapist Four Oaks Spinal & Sports Physiotherapy, Sutton Coldfield, West Midlands, B75 5ET, Annette Bishop Send response to journal: Re: Clinicians' frustration	To the Editor Koes, van Tulder and Thomas presented the Clinical Review – Diagnosis and treatment of low back pain (BMJ, 332, 1430-4) however some recent evidence is not included which may have altered some of their concluding remarks and influenced future back pain guidelines. The statement that “at present no reliable and valid classification system exists for most cases of non-specific low back pain” is of concern. Two recent papers have provided evidence of reliability of Mechanical Diagnosis and Therapy (MDT) for classifying patients with so-called non- specific low back pain (1, 2). This system uses the symptomatic and mechanical responses to repeated end range lumbar movements &/or static postures to classify patients into clinically separate and meaningful subgroups that helps to guide their management. Treatment is predicated on these responses and emphasises self-care. A key component of this assessment is the centralisation phenomenon (3). A systematic review of high quality studies of centralisation (4) concluded that the presence of centralisation was consistently associated with better clinical outcomes, and non-centralisation was an important predictor of poor outcomes. Centralisation is a useful and reliable clinical tool to classify those patients requiring directional specific exercises and postures. A recently published randomised clinical trial (5), referred to by Koes et al, using principles of MDT showed superior outcomes when subjects in the specific exercise group exercised according to their matched treatment (directional preference) compared with an unmatched treatment (opposite direction). An earlier study, which was not reviewed by Koes et al, also showed superior outcomes in the directional matched group when compared to the unmatched exercise group and the group randomised to usual (current guideline based) care (6). Had Koes et al included additional evidence in their review they may not have concluded that there is “strong evidence that specific back exercises are not effective.” An alternative conclusion was made by the Danish back pain guidelines in 1999 (7). If reliable and clinically useful tools are not recognised by reviews and guidelines why should we be surprised that clinicians do not implement the recommendations in the clinical environment? 1. Clare H, Adams R, Maher C. Reliability of the McKenzie spinal pain classification using patient assessment forms. Physiotherapy 2004;90:114- 9. 2. Kilpikoski S, Airaksinen O, Kankaanpää M, et al. Interexaminer reliability in low back pain assessment using the McKenzie method. Spine 2002;27:E207-14. 3. McKenzie R, May S. The Lumbar Spine. Mechanical Diagnosis and Therapy. Second ed. Waikanae, New Zealand: Spinal Publications New Zealand Ltd., 2003. 4. Aina A, May S, Clare H. The centralization phenomenon of spinal symptoms – a systematic review. Manual Therapy 2004; 9:134-143 5. Brennan G, Fritz J, Hunter S, et al. Identifying subgroups of patients with acute/subacute “nonspecific” low back pain. Results of a randomized clinical trial. Spine 2006;31:623-31. 6. Long A, Donelson R, Fung T. Does it matter which exercise? A randomized controlled trial of exercise for low back pain. Spine 2004;29:2593-602. 7. Danish Institute for Health Technology Assessment; Low-back pain. Frequency, management and prevention from an HTA perspective. Danish Health Technology Assessment; 1-106, 1999. Competing interests: None declared