Home / About Us / Blog / Mechanical Diagnosis and Therapy (MDT)

Mechanical Diagnosis and Therapy (MDT)


MDT is an acronym that represents “mechanical diagnosis and treatment”. It is often referred to in orthopedic physical medicine literature. MDT therapy is a specific assessment and treatment algorithm that uses coordinated movement patterns to classify and improve mechanical derangements and
dysfunctions. Mechanical pathologies account for ~80% of orthopedic conditions. Examples of mechanical pathologies would include strained or sprained soft tissue, abnormal adaptive tightness, scar tissue, obstruction from herniated discs, ligamentous tears, or the like.

Mechanical symptoms are differentiated from chemical symptoms, which chemical symptoms have been estimated to make up ~15% of orthopedic conditions. Chemically induced pathologies are associated with painful chemicals in tissue, especially with an accompanying inflammatory process. Using the MDT assessment algorithm, 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 osteoarthritis (OA) with MDT. MDT was primarily developed by The Mckenzie Institute. It has been thoroughly studied in the diagnosis and treatment of spinal pathologies. The aforementioned study Physical Therapists using MDT Therapy
is the first to look at MDT’s ability in assessing
peripheral joints.

Through this 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 exercises. 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 outcome 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 strongly lends to the concept that conventional physical therapy is a better alternative than no or home treatment for patients with knee OA, though not as effective as
conventional when combined with MDT.


When patients are assessed by an MDT trained therapist, the likelihood that a Wright Physical Therapists Implementing MDT Therapy
beneficial outcome will be established is exponentially higher than if standard conventional therapy methods are used alone. 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 actively working toward MDT certification or are certified through stringent testing over years of training. This exceptional mechanical diagnosis and therapy algorithm is powerful in classifying patients into a customized, skilled plan of care to progress them to the best outcomes possible. Please call one of our clinics below to schedule for treatment or referral. You can also find us at wrightpt.com.