Extract
Posterior impingement of the ankle results from the compression of
the talus and surrounding soft tissue between the tibia and the calcaneus and
has been likened to a "nut in a
nutcracker."1
It is produced by repetitive or forced plantar flexion of the foot and has
been described in female ballet dancers, athletes, and in nonathletes after an
ankle
sprain1-4.
Patients have pain in the posterolateral or posteromedial aspect of the ankle
with activity, particularly plantar flexion. Often there is tenderness medial
or lateral to the Achilles tendon, and soft-tissue thickening may be palpated.
A positive posterior impingement test consists of reproduction of the symptoms
with forced plantar flexion of the
ankle2. The
diagnosis is made on the basis of the history and physical examination of the
patient and the clinical judgment of the surgeon and is supported if the
symptoms are temporarily relieved by an injection of a local anesthetic and
steroid into the region of the posterior process of the talus through a
posterolateral
approach2.