Rupture of the Tibialis Posterior

- Physical Exam:
    - tenderness:
         - w/ involvement of PT tendon tenderness will be along course of this tendon just posterior tomedial crest of distal tibia, posterior to 
                the medial malleolus, or along undersurface of navicular;
                - after the tendon has ruptured, medial sided pain may improve;
         - w/ more advanced disease, lateral pain may occur from impingement of the the fibula against the calcaneus;
                - this may be more severe than the medial sided pain;
    - too many toes:
         - when viewed from behind, affected patients may demonstrate excessive abduction of the foot, which therefore causes more toes 
                to be seen on that side;
         - this sign may not be very sensitive for posterior tib rupture (ie, some patients with documented rupture will not demonstrate this sign);
    - heel rise:
         - most important test;
         - strength of tendon is assessed by a single heel rise test;
         - this is done by asking the patient to rest his or her hands on wall while the physcian views the feet posteriorly;
         - while one foot is raised, pt is first asked to go up on normal foot;
         - the heel should go into inversion, following which the heel will come off the ground strongly;
         - the affected heel will fail to invert, & longitudinal arch fails to rise during this maneuver;
         - note that some patients will be unable to perform a correct heel rise because of a painful tibialis posterior tendinitis (vs the inability 
                to perform heel rise due to tendon rupture);
    - motor strength:
         - the foot is first positioned in plantar flexion (which eliminates the tibialial anterior as a potential foot invertor) as well as inversion;
         - the examiner than attempts to evert the foot against resistance;
    - evaluate for fixed deformity:
         - assess for equinus contracture (w/ heel in varus)
         - ROM of the ankle and subtalar joints;
         - assess for relative supination deformity of the midfoot (which is revealed when the hindfoot is placed in a corrected position)

Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Monday, December 5, 2011 4:09 pm