Positive Health Online

Earlier this year media publicity made much of the 'news' that chiropractic and osteopathic manipulation 'does not work'.

This must have come as a surprise to the millions of people in the UK who have first hand experience that – when appropriately applied – it does 'work'.

So what was the background to the news report?

Firstly, the opinions expressed were NOT based on original research, but on what the authors Professor Edzard Ernst (and a colleague)[1] called a 'systematic review of systematic reviews' of manipulation.

Based on this, they concluded that manipulation offered little value in regard to treatment of neck and back pain.

Writing in the Journal of the Royal Society of Medicine, they claim that the data gave 'little evidence of effectiveness, despite many individual studies that do show benefit'.[2]

Professor Ernst, writing with his colleague, have re-worked their findings several times, for example in 2005 in the Wiener Klinische Wochenschrift,[3] as well as writing on his own this time, in a more general review of methods of treating musculoskeletal pain.[4]

In that general review Ernst highlighted the usefulness of massage (which he practised as a medical student many years ago), but questioned spinal manipulation's value in treatment of back pain:

"For acute back pain, spinal manipulation [high velocity, low amplitude thrust – HVLA] was superior to sham therapy and to treatments known to have detrimental effects on back pain. Spinal manipulation generated no advantage over general practitioner care, analgesics, physical therapy, exercise or back school. For chronic back pain, the results proved to be similar".

If we look carefully at this statement we can come to at least one obvious conclusion, based on Ernst's own comments, manipulation is NOT valueless, only that (based on Ernst's evaluation – which is questionable as will be shown below), it is no more beneficial in offering relief to back pain sufferers than use of pain-killers, physical therapy (which nowadays often includes manipulation), exercise, etc.

Systematic Reviews of 'Systematic Reviews'

And can we take 'systematic reviews of systematic reviews', on which these opinions are based, seriously?

Let's analyze what it is that is being evaluated.

The symptom under review is non-specific-low back pain.

The review that Ernst and colleague have conducted appears to start with a built-in, but clearly incorrect assumption, that all back pain is the same. Back pain may have a wide variety of causes, ranging from biomechanical to pathological, psychological and functional. The pain may derive from (among other possibilities) intervertebral disc problems, facet joint dysfunction, hyper- or hypo-mobility of spinal segments, muscular and/or ligamentous imbalances, sacro-iliac restrictions, trigger point activity, as well as disturbed emotion/somatization – making it a virtual certainty that acute or chronic back pain could not possibly be expected to respond to a single intervention, whether manipulation or anything else.

And then there is the word 'manipulation'. This word may mean high velocity/ low amplitude thrust (HVLA), or it might refer to mobilizing articulation, or soft tissue methods, such as Muscle Energy Technique, ligamentous balancing, Myofascial Release, Strain-Counterstrain techniques, or combinations of these, amongst others – usually combined with exercise.

To those unfamiliar with these methods, it is necessary to say that there can hardly be more diverse methods for modifying tissue status, or mobilizing joints, than those listed.

There is frequently therefore no uniformity in application of osteopathic or chiropractic manipulation, apart from the fact that one or the other, or a combination of these methods might be employed. This is not a criticism of the use of a range of manipulation methods in this way, since a selection of diverse approaches is essential if patients are to receive individualized attention. However, it is a criticism of reviewers who attempt to homogenize outcomes, where actual treatment – uniformly listed as 'manipulation' – might have involved all or any of the methods mentioned.

And even where HVLA is the specified intervention, there are a wide range of possibilities as to how, and where this has been applied, making evaluation of 'manipulation' for 'back pain' a virtually meaningless exercise, or at best a questionable one.

So we are looking at a review of reviews of a series of research studies where non-similar treatment approaches (even though they all involve manually applied modalities) have been used to treat non-similar conditions (even though they all have back pain in common).

The answer is predetermined. The outcome is virtually guaranteed to show no benefit for ALL back pain conditions when such a meaningless assessment is carried out. The certainty is that, in these circumstances, 'manipulation does not work'.

At best, the jury is out as to whether reviewing reviews is a legitimate method, unless you have a large number of high quality studies to evaluate. And this is not the case with back pain and manipulation, for the very good reasons that the review makes the mistaken assumption that all back pain is the same; and that manipulation is in some way homogenous.

Question: When does manipulation work?
Answer: When it is applied to a condition that can benefit from its use.

Categories and classification models for low back pain (LBP):[5]-[6]

Professor Ernst and his colleague may or may not be aware that categorization of problems such as back pain can predict, with some accuracy (up to 95%),7 which forms of back pain will, and which will not, respond to manipulation.[8]-[9]

There is no indication as to which, if any, of the studies in their 'systematic review of systematic reviews' used categorization in selection of patients to receive manipulation.

Because a patho-anatomical diagnosis is only available in approximately 20% of all low back pain cases, the identification of sub-groups of patients with low back pain who are likely to respond favourably to particular therapeutic interventions has been (and continues to be) an important objective of clinical research.[10]

A recent randomized clinical trial7 has put this concept to the test as follows:

Patients with low back pain of less than 90 days duration, who had been referred for physical therapy, were examined before treatment and classified into one of three sub-groups based on the type of treatment believed most likely to benefit the patient:

• Manipulation;

• Stabilization exercise;
• Specific exercise.

The patients were then randomly assigned to receive either manipulation, stabilization exercises, or specific exercise treatment during a four-week treatment period.

Disability was assessed in the short-term (four weeks) and long-term (one year) using the Oswestry Disability Index.

Comparisons were made between patients receiving treatment matched (i.e. the treatment they received was appropriate for the sub-group to which they had been assigned following assessment) to their sub-group, versus those receiving unmatched treatment (i.e. those who received treatment inappropriate to their category, based on assessment).

• A total of 123 patients participated (mean age, 37.7 +/- 10.7 years; 45% female);

• Patients receiving matched treatments experienced greater short- and long-term reductions in disability than those receiving unmatched treatments;
• After four weeks, the difference favouring the matched treatment group was 6.6 Oswestry points (95% CI, 0.70-12.5), and at long-term follow-up the difference was 8.3 points (95% CI, 2.5-14.1).

Conclusion:

1. Nonspecific low back pain should not be viewed as a homogenous condition;
2. Outcomes can be improved when sub-grouping is used to guide treatment decision-making;
3. Manipulation works – when it is applied to those who are likely to benefit.

References

1. Ernst E and Canter P. A systematic review of systematic reviews of spinal manipulation. J R Soc Med. 99: 189-193. 2006.
2. Assendelft W, Morton S, Yu E et al. Spinal manipulative therapy for low back pain. A meta-analysis of effectiveness relative to other therapies. Ann Intern Med. 138: 871-881. 2003.
3. Canter P and Ernst E. Sources of bias in reviews of spinal manipulation for back pain. Wiener Klinische Wochenschrift. 117(9-10): 333-341. 2005.
4. Ernst E. Musculoskeletal conditions and complementary/alternative medicine. Best Practice and Research. Clinical Rheumatology. 18(4): 539-556. 2004.
5. McKenzie R. The Lumbar Spine: Mechanical Diagnosis and Therapy. Waikanae. New Zealand. Spinal Publications. 1981.
6. McKenzie R and May S. The Lumbar Spine: Mechanical Diagnosis and Therapy. Waikanae. New Zealand. Spinal Publications. p 553-563. 2003.
7. Brennan G, Fritz J, Hunter S et al. Identifying sub-groups of patients with acute/sub-acute 'nonspecific' low back pain: results of a randomized clinical trial. Spine. 31(6): 623-31. 2006.
8. Delitto A, Erhard RE and Bowling RW. A treatment-based classification approach to low back syndrome: identifying and staging patients for conservative management. Physical Therapy. 75: 470-479. 1995.
9. Fritz JM, Delitto A and Erhard RE. Comparison of classification-based physical therapy with therapy based on clinical practice guidelines for patients with acute low back pain: a randomized clinical trial. Spine. 28. 1363-1372. 2003.
10. Borkan JM, Koes B, Reis S et al. A report from the second international forum for primary care research on low back pain: re-examining priorities. Spine. 23. 1992-1996. 1998.