Yoga & Mechanical Diagnosis and Treatment (MDT)

Robin McKenzie, a physical therapist from New Zealand, revolutionized the treatment for LBP in the 1950s. McKenzie discovered symptom centralization by using repeated movements or sustained postured.  Mechanical Diagnosis and Treatment (MDT) is a tool for assessment, treatment and prevention of musculoskeletal disorders.  McKenzie is an advocate for independent management of a person’s own back pain.  He said,

“I believe the treatment dependency is undesirable and should be avoided where possible. Therefore, in addition to whatever treatment is necessary for present symptoms, the patient should be taught to become self-reliant and independent of the therapist in the management of future low back pain” RA McKenzie, 19811

McKenzie advocates patient education to prevent the recurrence of low back pain. It can be safe to assume that he would support the daily yoga practice as long as it is individualized to the student’s needs. MDT consists of three categories for diagnosing back pain: Postural, Dysfunction and Derangement. A specific style yoga may be the key to a person’s self-management of their back condition.  By understanding the treatment strategies of physical therapists, yoga can be applied appropriately.

Postural Syndrome

Postural Syndrome is when normal tissues are placed on end range stretch for prolonged periods of time. It is insidious in nature and can be hard to reproduce.  The yoga student with a postural syndrome will have pain or symptoms that increase throughout the day. They may have a job where they sit for long periods of time or have a medical condition that causes abnormal posture.  Postural Syndrome is from sustained poor posture.

Postural education and exercises can address any muscle strength imbalances which underlie postural dysfunctions. Postures that open up the chest and strengthen antigravity muscles will help address these deficits.  Specific yoga classes that focus on posture, such as Iyengar yoga, are appropriate.  A study completed in 2009 compared 24 weeks of Iyengar Yoga to conventional interventions for LBP. The yoga group had greater improvements in functional disability, pain, depression and a reduction in pain medication.2 A yoga teacher who understands muscle imbalance and compensatory movement patterns will help a student overcome their postural syndrome.


Abnormal or dysfunctional tissues often cause low back pain.  Dysfunctional tissues cause pain when placed on end range stretch or placed under mechanical deformation (palpation). A physical therapist uses repeated movements to determine if their client has dysfunctional tissues. Symptoms will either decrease or stay the same with repeated motion into the painful direction. Muscle guarding and spasms, facet joint restrictions or adhesions in the fascia can cause dysfunction of the back. These restrictions may result from previous trauma, inflammatory or degenerative processes.3  Research agrees that compensatory strategies may develop as a result of habits formed due to previous injury4,5.  This may cause habituated abnormal movement patterns that perpetuate the dysfunctional tissues.

The repeated motion that is used to diagnose dysfunction in the clinic is also used to treat.  This can easily be applied to a yoga class, but difficulty arises when there is a mixed class of dysfunctions.  Someone may have a flexion dysfunction due to quadratus lumborum (back) spasm.  They need a gentle class consisting of forward folds and twists.  Those with tight iliopsoas (hip flexor) will enjoy erected postures, gentle extension and lunges. Most yoga asanas can be placed into a direction specific exercise group and can be used to treat specific dysfunctions (Specific Exercise PDF). Back Care, restorative and a beginner yoga class will help a majority of people with dysfunction. Themed classes, such as psoas release or stiff back classes, might help to separate people into groups based off of their dysfunction.  Class should consist of hands on assists that are massage-like and repetitive movements that flow with the breath.


Derangements are often thought to be discogenic in nature.  Discogenic in nature implies that a nerve root is being pinched, either due to decreased vertebral disc height or a bulge or herniation.  A crucial symptom for diagnosing a derangement is the migration of pain in response to repeated motions.  Centralization occurs when a movement or position relieves the pain or causes it to move towards the spin.  If the pain centralizes with a forward fold, that means it migrates proximally.  If it peripheralizes, the pain migrates distally from the spine, down the leg or to the foot.  Directional Preference is similar to centralization, but more specific to a position in which one finds relief from pain.  Centralization with movement indicates a better prognosis than directional preference alone.6 Despite this finding, directional preference is used for exercise prescription. A study found matching directional preference with specific exercise decreased pain and medication use.7  For treatment of derangement, it first must be reduced.  This is done using either specific movements, manipulation or mobilizations by a trained professional.  Next, the patient needs to perform exercises to increase the stability of the spine and normalize posture.

Individualized yoga classes will help a person with a derangement recover faster and manage their symptoms better, although direct communication with a physical therapist is recommended.  Understanding their directional preference and what movements cause the symptoms to centralize will help the teacher tailor the practice to meet their needs.  Often, a person can go from a derangement to dysfunction.  In order to prevent this, yoga as therapy must be applied appropriately.

It is a challenge for a yoga teacher to meet the needs of every student. A partnership between the teacher and a physical therapist may help alleviate the burden.  If a studio offers back care classes, they must accept the responsibility of providing the best care possible.  An understanding of the student’s symptom behavior is necessary to determine the best class for them.  A thorough intake form may be helpful in screening a student for a serious condition and to understand the nature of the student’s symptoms (Intake Form).  Keeping classes small and offering them in a series may help reduce the unnecessary risk of exacerbating symptoms. It is possible for physical therapy and yoga to partner in providing long term care for low back patients using the principles of MDT. Understanding MDT and the terms will improve communication between yoga teachers and physical therapists.


  1. Moore, Jeff, DPT. Incorporating Repetitive Movement. (Power Point Presentation) Masterminds Mentorship Group. 4 November 2015.
  2. Williams, K., Abildso, C., Steinberg, L., Doyle, E., Epstein, B., Smith, D., … Cooper, L. (2009). Evaluation of the effectiveness and efficacy of Iyengar yoga therapy on chronic low back pain. Spine, 34(19), 2066–76.
  3. McKenzie and May, The Lumbar Spine, Mechanical Diagnosis and Therapy, Vol I & II, Spinal Publications Limited, P.O. Box 2, Waikanae, New Zealand, 2003.
  4. Lee DG, Lee LJ, McLaughlin L. Stability, continence and breathing: The role of fascia following pregnancy and delivery. J Body Move Ther. 2008;12(4):333-348. doi:10.1016/j.jbmt.2008.05.003.
  5. Moseley GL, Hodges PW. Reduced variability of postural strategy prevents normalization of motor changes induced by back pain: a risk factor for chronic trouble? Behav Neurosci. 2006;120(2):474-476. doi:10.1037/0735-7044.120.2.474.
  6. Werneke MW, Hart DL, Cutrone G, et al. Association between directional preference and centralization in patients with low back pain. J Orthop Sports Phys Ther. 2011;41(1):22-31. doi:10.2519/jospt.2011.3415.
  7. Long A, Donelson R, Fung T. Does it matter which exercise? A randomized control trial of exercise for low back pain. Spine (Phila Pa 1976). 2004;29(23):2593-2602. doi:00007632-200412010-00002