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Mechanical Therapy (MDT)

What makes it so effective in the spine also makes it powerful in the peripheral joints.


MDT represents the phrase “mechanical diagnosis and treatment” and is often found in orthopedic physical medicine literature. MDT is a specific assessment tool that uses directional preference movement to assess and improve mechanical dysfunctions. Mechanical dysfunctions account  for ~ 80% of orthopedic conditions and can be succinctly defined as an abnormal resting position of a joint or soft tissue. Examples of this would be tissue with abnormal stretch, abnormal tightness, strains, sprains, scar tissue or the like.

Mechanical dysfunctions are different than chemical dysfunctions, which make up ~15% of orthopedic conditions. Chemically mediated pathologies are associated with caustic chemicals found in tissue, especially with an inflammatory process. The other ~5% of pathologies are related to behaviorally mediated conditions. Using the MDT assessment, patients are powerfully classified into specified subgroups of derangement, articular dysfunction, or contractile dysfunction based on movement characteristics.


A first of its kind research article has been published recently in the Journal of Orthopedic and Sports Physical Therapy regarding the treatment of knee OA with MDT. MDT, also known as The Mckenzie Method, has been  thoroughly studied in the diagnosis and treatment of spine pathology. The aforementioned study is the first to look at its ability in assessing peripheral joints.

Through the study, researchers observed 180 patients with knee OA who planned to undergo Total Knee Replacements. Of the 180 patients, 40 were classified as MDT responders and were given directional preference exercises. 59 were classified as MDT non-responders and were given conventional evidenced-based physical therapy exercise. The remainder of the patients were placed into the control group and received no treatment.

The study discovered that those patients who were classified into the MDT “responders” group had significantly greater scores on their functional outcomes measures than those that performed conventional physical therapy exercise or those in the control group. Noted in this study was that the conventional physical therapy group scored significantly better than the control group. This indicates that conventional physical therapy is a better alternative than no or home treatment for patients with knee OA.


When patients are assessed mechanically by an MDT trained therapist, the likelihood that a beneficial directional preference will be established is exponentially higher. Furthermore, you can have higher expectations that your patient’s outcomes will be improved over just performing conventional physical therapy or home exercise treatment.
At Wright Physical Therapy, all of our doctors of physical therapy are MDT certified, or are actively working toward certification. This method of assessment is an exceptional tool for classifying patients into a customized and skilled plan of care and assisting them to the best outcomes possible with conservative treatment you may deem appropriate. Please contact bryan@wrightpt.com with questions regarding MDT treatment.