Long-term results of the Chrisman-Snook operation for reconstruction of the lateral ligaments of the ankle.

The Chrisman-Snook procedure for instability of the lateral ankle ligaments, first described in 1969, reconstructs the anterior talofibular ligament and the calcaneofibular ligament using one-half of the peroneus brevis tendon, routed through tunnels in the fibula and calcaneus. In the present long-term evaluation of the results of this procedure, forty-eight of sixty ankles, in fifty-seven patients, were assessed after a mean follow-up of ten years (range, four to twenty-four years). The results were excellent in thirty-eight ankles, good in seven, fair in two, and poor in one. The two ankles with a fair result were improved but still had some persistent instability, while the ankle with a poor result (no improvement) was in a patient with generalized ligament laxity. All three patients with a fair or poor result had had a severe reinjury to the ankle. Based on the findings in this study, we concluded that this procedure will restore good long-term function in a high percentage of patients who are disabled by ankle instability due to unhealed or neglected tears of the lateral ligaments.