The McKenzie Method of Mechanical Diagnosis and Therapy (MDT)

A selection of articles supporting the effectiveness of the McKenzie Method, one of the services provided by the Rob Orr Pain Clinic.

A Study Exploring the Prevalence of Extremity Pain of Spinal Source

objectives

To investigate the proportion of patients that present with isolated extremity pain who have a spinal source of symptoms and evaluate the response to spinal intervention.

methods

Participants (n = 369) presenting with isolated extremity pain and who believed that their pain was not originating from their spine, were assessed using a Mechanical Diagnosis and Therapy differentiation process. Numerical Pain Rating Scale, Upper Extremity/Lower Extremity Functional Index and the Orebro Questionnaire were collected at the initial visit and at discharge. Global Rating of Change outcomes were collected at discharge. Clinicians provided MDT 'treatment as usual'. A chi-square test examined the overall significance of the comparison within each region. Effect sizes between spinal and extremity source groups were calculated for the outcome scores at discharge.

Results

Overall, 43.5% of participants had a spinal source of symptoms. Effect sizes indicated that the spinal source group had improved outcomes at discharge for all outcomes compared to the extremity source group.

Discussion

Over 40% of patients with isolated extremity pain, who believed that their pain was not originating from the spine, responded to spinal intervention and thus were classified as having a spinal source of symptoms. These patients did significantly better than those whose extremity pain did not have a spinal source and were managed with local extremity interventions. The results suggest the spine is a common source of extremity pain and adequate screening is warranted to ensure the patients ́ source of symptoms is addressed.

additional information

Hip 71% Knee 25% Ankle/Foot 29% Shoulder 49% Elbow 44% Wrist/Hand 38%

Average = 43.5%

An Overview of Supportive Studies from the McKenzie Institute International

Richard Rosedale PT, Dip. MDT, Robert Medcalf PT, Dip. MDT

The McKenzie Method of MDT continues to be one of the most researched conservative approaches to musculoskeletal problems available. It has been examined in depth in relation to its utility in the spine, and the research is accumulating to support its use in the extremities.

The following is a small selection of some of the most important studies on the approach to date, with an explanation of their significance.

Assessment Reliability

It is fundamentally important that any system of assessment and treatment has established reliability: Reliability means that different examiners will agree on the assessment findings and reach the same patient classification. Since treatment decisions rely exclusively on the assessment and classification, this is critical.

The following four studies demonstrate that the McKenzie Method, when applied by Credentialed or Diplomaed clinicians to the spine and extremities, found good to almost perfect reliability using a concurrent reliability design: Kilpikoski S, et al.

(1)Inter-examiner reliability of LBP assessment using the McKenzie method. Spine15;27, 2002 Clare HA, et al.

(2)Reliability of McKenzie classification of patients with cervical or lumbar pain. JMPT 28, 2005 Heidar Abady A, et al.

(3)Inter-examiner reliability of diplomats in the MDT system in assessing patients with shoulder pain. JMMT 22, 4. 2014 Willis S, et al.

(4)Inter-rater reliability of the McKenzie System of MDT in the examination of the knee. JMMT Published online 07 Sept 2016

Treatment Efficacy

The following RCTs endorse the treatment value of MDT, showing efficacy in the spine and in the extremity. Long A, et al. Does it matter which exercise? A RCT of exercises for LBP. Spine; 29:2593-2602. 2004.

This groundbreaking study clearly endorses the value of sub-classifying our patients using a McKenzie assessment, establishing directional preference and matching specific exercises based upon these findings. All patient outcomes including pain, function and medication use were dramatically affected. Petersen T, et al.

The McKenzie Method Compared with Manipulation When Used Adjunctive to Information and Advice in LBP Patients Presenting with Centralization or Peripheralization. A RCT. Spine Vol 36, 24. 2011 With a one year follow-up, this study compared two alternative LBP interventions. The McKenzie Method was found to be more effective than manipulation, and the study gives support to the Method's classification based approach.

Albert H, Manniche C. The Efficacy of Systematic Active Conservative Treatment for Patients with Severe Sciatica. A Single-Blind, Randomized, Clinical, Controlled Trial. Spine Vol 37, 7. 2012 The patients in this study had symptoms that would normally qualify them for surgery. The patients given directional preference exercises determined by the McKenzie Method improved significantly more with respect to global improvement, sick leave, vocational status, root compression signs, and patient satisfaction.

Efficacy with Psychosocial Factors

Numerous studies have explored the effect of MDT on psychosocial outcomes. There have been positive effects in relation to fear avoidance, fear and disability beliefs, somatization, depressive symptoms and pain self-efficacy. Werneke M, et al. Change in psychosocial distress associated with pain and functional status outcomes in patients with lumbar impairments referred to PT services. JOSPT. 41:969-980, 2012

Data from 586 patients with LBP showed that those who demonstrated non-centralization (37%) had significantly worse pain, functional disability and psychosocial distress outcomes compared to those who centralized (45%). Mbada C, et al. Comparative efficacy of three active treatment modules on psychosocial variables in patients with long-term mechanical low- back pain: a randomized-controlled trial, Archives of Physiotherapy. 5, 10, 2015.

This RCT looked at psychosocial outcomes in patients with lumbar Derangement responding to the extension principle, given directional preference exercises alone and in combination with strengthening. At 4 and 8 weeks all groups demonstrated significant improvements on all measures of beliefs and fear avoidance.

Rosedale R, et al. Efficacy of Exercise Intervention as Determined by the McKenzie System of Mechanical Diagnosis and Therapy for Knee OA: A RCT. JOSPT. Vol 44, No.3. 2014

Patients given exercises based on an MDT assessment had superior outcomes compared to those of wait-list controls. 40% of the knees examined were classified as Derangements; they demonstrated large effect sizes at two weeks for all primary outcomes and up to large effect sizes at three months. This demonstrated success with a population with severe knee OA awaiting potential knee joint replacement.

Avoiding potential surgery and cost saving implications

Several studies have shown the potential of MDT for pre-surgical screening and intervention to reduce surgery rates in the spine. This could have significant cost-saving implications. In the first study, four years after implementation of McKenzie based spine clinics in a Danish county, lumbar disc surgery rates were reduced by 50% compared with previous years.

In the second study, transforaminal epidural injections followed by MDT demonstrated the potential to be an effective strategy in preventing surgical interventions for patients with lumbar disc herniation.

(1)Rasmussen C, et al. Rates of Lumbar Disc Surgery Before and After Implementation of Multidisciplinary Nonsurgical Spine Clinics. Spine 30, 21. 2005 Van Helvoirt H, et al.

(2)Transforaminal Epidural Steroid Injections Followed by MDT to Prevent Surgery for Lumbar Disc Herniation. Pain Med.15(7). 2014

Systematic Reviews and Guidelines featuring The McKenzie Method

MDT and the phenomenon of Centralisation and Directional Preference have been the subject of, or included in, many systematic reviews and guidelines. Here few a few examples; May S, Alessandro A. Centralisation and directional preference: a systematic review. Manual Therapy 17, 497-506, 2012. This review found that centralisation and directional preference had been reported in 62 studies. The majority of evidence was supportive of these responses as being reliably assessed and associated with a good prognosis.

Stynes S, et al. Classification of patients with LB-related leg pain: a systematic review. BMC MSK Disorders 17:226, 2016. This review evaluated 22 systems that classify populations with low back-related leg pain. MDT scored the highest of any system, with criteria based upon purpose, validity, feasibility, reliability and generalisability.

For further information about MDT please click the link https://mckenzieinstitute.org/

The cost impact of quality-assured mechanical assessment in low back pain care, Dr Ron Donelson, JMMT 2019

This study published by Dr Rob Donelson compares the cost impact of quality-assured mechanical assessment in low back pain care using the McKenzie Method (MDT) compared to other modalities.

5036 patients medical costs and claims were analysed one year following their initial appointment concerning the cost and healthcare usage.

Total Cost

51.48% less costs using MDT

MRi Performed

49% less MRIs required using MDT

Spinal Injections

39% less injections required using MDT

This outcome clearly demonstrates that when using MDT for the assessment and treatment of low back pain there is less usage of imaging scans, injections, and surgeries.