Objective:

The primary aim of this systematic review was to determine the efficacy of non-surgical classification systems for treating LBP compared to general comparators for patient-reported LBP intensity, leg pain intensity and disability. A secondary aim was to determine the effectiveness of treating sub-classes of classification systems.

Design:

Systematic review with meta-analysis

Results:

There were twenty-five articles included in the classification system analyses and 38 articles included in the sub-class analyses. Of the 25 classification trials, three used the Movement System Impairment, three Treatment Based Classification, nine McKenzie, four STarT Back Tool, one classification-based Cognitive Functional Therapy, one Specific Treatment of Problems of the Spine, and four other systems.

For back pain intensity:

There was low certainty evidence that classification systems were more effective than all comparators for reducing back pain intensity at end of intervention and intermediate-term.

Subgroup analyses for classification systems on back pain intensity: No individual classification system was more effective than generalist interventions for reducing back pain intensity at any time point

For leg pain intensity:

There was very low certainty evidence that classification systems were not more effective than all comparators for reducing leg pain intensity at the end of intervention. There was very low to moderate certainty evidence of no significant differences between classifications systems and all comparators at short-, intermediate- and long-term follow-up timepoints.

The authors did not complete subgroup analyses on classification systems for leg pain intensity due to the lack of trials.

For disability:

There was low certainty evidence that classification systems were more effective than all comparators for reducing disability at end of intervention and long-term.

Subgroup analyses for classification systems for disability: There was moderate certainty evidence that the McKenzie system was significantly more effective than all comparators for reducing disability in the intermediate-term. No other significant results were observed for the type of classification system at any time point

Conclusion:

The author’s reported low certainty evidence of a small non-clinically meaningful effect at end of intervention for patient-reported LBP intensity and disability, but not leg pain intensity, in favor of classified interventions compared to generalized comparators. The 95% prediction interval for all main analyses showed wide dispersion and included beneficial effects for both classification systems and comparators. Only the McKenzie approach had benefits on disability in the intermediate term, albeit the effect estimate was not clinically significant. No other significant results were observed for classification system type at any other timepoint. The type and duration of pain may change treatment significance, however, the effect size remained small.

There is currently insufficient evidence supporting the use of classification systems instead of general interventions for managing LBP.

Implications for MDT clinician:

As noted above, this systematic review with meta-analyses looked at several different classification systems. I am going to primarily comment on the MDT or “McKenzie system” results and discussion brought up in the systematic review.

MDT clinicians reading through the article and the above review may be somewhat confused as this seems inconsistent with what they see every day in the clinic and on courses. They may have read numerous articles over the years reporting on the effectiveness of the MDT assessment and treatment and so be disappointed to read the conclusions of this review. The following are some points that come to mind when considering this review:

Two of the included MDT studies’ (Garcia et al 2013, Garcia et al 2018) had treatment groups where the interventions were performed by a clinician/s with less-than-optimal training:
- Garcia et al 2013 - “It is documented that the therapists who gave the McKenzie management were fully certified, but in fact had only completed a Part A course.” https://mckenzieinstitute.org/clinicians/research-and-resources/reference-list/lumbar%3A-trials/
- Garcia et al 2018 - “The single treating therapist for the McKenzie group had only completed McKenzie Part A, 3 years prior to the trial. Research has shown a much more reliable classification when performed by credentialed and diploma holders (Razmjou et al 2000, Kilipkoski et al 2002, and Clare et al 2005).” https://mckenzieinstitute.org/clinicians/research-and-resources/reference-list/lumbar%3A-trials/
In one included MDT study (Bid et al 2017) there was no mention of what level of training the MDT therapist had (see Tagliaferri et al 2022 in table 2 on p. 47).
In three of the MDT based studies (Cherkin et al 1998, Machado et al 2010, Miller et al 2005) MDT assessment took place AFTER randomization. Donelson 2007 discussed this in his book Rapidly Reversible Low Back Pain, as randomization occurring BEFORE assessment could affect the results with some “non-responders” or what we now call mechanically inconclusive or mechanically unresponsive radiculopathy patients being included will obviously show less than optimal results (Long et al 2004 did the opposite of this). However, Tagliaferri et al 2022 discussed what they felt were shortcomings of prior reviews as they included studies that “are not tailored to the individual, and trials that do not use all the sub-classes of the classification system... This is an issue given the effect may reflect treatment of only a sub-class and not the whole classification system.”
Several of the included MDT studies didn’t fully report on the appropriate dosage performed or specific type of protocol they used. This again could affect findings as patients classified with either Derangement or Dysfunction syndromes need very specific dosages.
Long et al 2004 which has been included in other SRs (Clare et al 2004, Lam et al 2018, Sanchis-Sanchez et al 2020) was not included in Tagliaferri et al 2022 except for being looked at in the sub-class analyses.
Additionally, per the authors: “Given McKenzie management is primarily focused on pathoanatomical features of pain, integration of directional preference management into a biopsychosocial approach could be further investigated to maximize treatment outcomes. Overall, the McKenzie system, and sub-classes thereof do not produce clinically meaningful effects alone for LBP management compared to generalist comparators and further improvement of the approach is required to justify its widespread use in clinical practice.”
- This generalization appears reveal a clear misunderstanding of the method as centered on the individuals’ symptomatic response, rather than on any pathoanatomical features. McKenzie and May 2003 and MDT course manuals both reference numerous sources discussing the problems with relying too much on the pathoanatomical approach in addition to describing the importance of communication and therapeutic alliance emphasizing the importance of what the authors describe as the “biopsychosocial approach”. MDT has incorporated aspects of this for decades now in their educational system.

Tagliaferri et al 2022 should be commended for tackling such an important topic such as classification approaches as this is an area that still warrants more investigation, but based on what this current reviewer can determine, it seems similar pitfalls as previously described with included studies that do not utilize MDT appropriately with adequately trained clinicians. Clinicians and researchers carrying out studies based on MDT assessment and treatment may need to look more closely at their methodology when carrying out their studies. This is important to make sure they optimize how the system should be applied, taking into consideration that the study may be included in future systematic reviews.

References:

Tagliaferri et al 2022. Classification approaches for treating low back pain have small effects that are not clinically meaningful: a systematic review with meta-analysis. JOSPT 2022 Volume 52 Issue 2 pp. 67-84.

Garcia et al 2013. Effectiveness of back school versus McKenzie exercises in patients with chronic nonspecific low back pain: a randomized controlled trial. Phys Ther. 2013;93:729-747.

Garcia et al 2018. McKenzie Method of Mechanical Diagnosis and Therapy was slightly more effective than placebo for pain, but not for disability, in patients with chronic non-specific low back pain: a randomised placebo controlled trial with short and longer term follow-up. Br J Sports Med. 2018;52:594-600.

Bid et al 2017. A Study on Central Sensitization in Chronic Non-specific Low Back Pain. Indian J Physiother Occup Ther. 2017;11(4):165-175.

Cherkin et al 1998. A comparison of physical therapy, chiropractic manipulation, and provision of an educational booklet for the treatment of patients with low back pain. N Engl J Med. 1998;339:1021-1029.

Machado et al 2010. The effectiveness of the McKenzie method in addition to first-line care for acute low back pain: a randomized controlled trial. BMC Med. 2010;8:10

Miller et al 2005. A comparison of the McKenzie approach to a specific spine stabilization program for chronic low back pain. J Man Manip Ther. 2005;13:103-112.

Donelson, R. 2007. Rapidly reversible low back pain: an evidence-based pathway to widespread recoveries and savings. SelfCare First, LLC 2007.

Long et al 2004. Does it matter which exercise? A randomized control trial of exercise for low back pain. Spine (Phila Pa 1976). 2004;29:2593-2602.

Peterson et al 2002. The effect of McKenzie therapy as compared with that of intensive strengthening training for the treatment of patients with subacute or chronic low back pain: a randomized controlled trial. Spine (Phila Pa 1976). 2002;27:1702-1709.

Peterson et al 2007. One-year follow-up comparison of the effectiveness of McKenzie treatment and strengthening training for patients with chronic low back pain: outcome and prognostic factors. Spine Phila Pa 1976. 2007;32(26):2948-2956.

Clare et al 2004. A systematic review of efficacy of McKenzie therapy for spinal pain. Aust J Physiother 2004;50:209–16.

Lam et al 2018. Effectiveness of the McKenzie Method of Mechanical Diagnosis and Therapy for Treating Low Back Pain: Literature Review With Meta-analysis. JOSPT 2018 Volume 48 Number 6: 476-490.

Sanchis-Sanchez et al 2020. Effectiveness of mechanical diagnosis and therapy in patients with non-specific chronic low back pain: a literature review with meta-analysis. Brazilian Journal of Physical Therapy 2020 Volume 25, Issue 2, Pages 117-134.

McKenzie, R., May, S. (2003) The lumbar spine: Mechanical diagnosis and therapy Vol. 1 and 2. Spinal Publications, New Zealand, Ltd.

McKenzie Institute USA (2012, 2013, 2014). Mechanical diagnosis and therapy course manuals A, B, C, D and Advanced Extremities.

Machado et al 2006. The McKenzie method for low back pain: A systematic review of the literature with a meta-analysis approach. Spine 2006;31:E254–62.

Donelson 2022. Rapid Recoveries Without Surgery for Back, Neck, and Joint pain: The Power of a Precise Diagnosis. SelfCare First, LLC 2022.

Lumbar: Systematic Reviews