Treatment of lateral instability of the ankle--a new modification of the Evans repair.

A modification of the Evans repair using only half of the peroneus brevis tendon was applied in the treatment of 34 patients with chronic functional lateral instability of the ankle. With a median follow-up of 25 months, 32 patients were examined. Functional stability was achieved in all but one patient. This modification of Evans' repair is recommended, as it is technically easy, gives good functional stability, and has the theoretical advantage of saving an important pronator of the foot.