Surgical Treatment of Chronic Lateral Ankle Instability Using an Inferior Extensor Retinaculum Flap: A Retrospective Study

Chronic lateral ankle instability causes significant problems with physical activity. The purpose of the present study was to evaluate the results of ligamentous retensioning combined with reinforcement using an extensor retinaculum flap. A consecutive series of 38 patients were included with a minimum follow-up duration of 2 years. The functional results were assessed using the Karlsson and American Orthopaedic Foot and Ankle Society scale scores. The pre- and postoperative radiologic assessment was performed using stress radiographs to measure varus tilt and anterior drawer tests. All 38 patients were followed up for 2.5 to 7.2 years, and 35 patients were satisfied. The American Orthopaedic Foot and Ankle Society scale score had improved significantly from 57 (range 20 to 70) points preoperatively to 95 (range 80 to 100) points postoperatively (p < .0001), and 35 patients believed their ankle was more stable after surgery. The patients had returned to their previous sports activities an average of 4.7 (range 2 to 12) months after surgery. On the stress radiographs, the mean talar tilt angle had improved significantly from 15.2° (range 6° to 26°) preoperatively to 3.8° (range 1° to 8°) at the final follow-up visit (p < .001), and the mean anterior talar had improved significantly from 13.2 (range 8 to 18) mm preoperatively to 4 (range 4 to 7) mm at the final follow-up visit (p < .002). Regarding the prognostic factors, a link was found between the functional result and residual radiologic laxity measured on the stress radiographs. Reconstruction of the lateral ligaments for chronic ankle instability combining capsuloligamentous retensioning and reinforcement with an extensor retinaculum flap resulted in successful outcomes, excellent ankle stability, and preservation of ankle joint mobility. This technique addressed both lateral ankle and subtalar instability by developing an extraarticular interosseous ligament.