An analysis of outcome measures following the Brostrom-Gould procedure for chronic lateral ankle instability

Background: The Brostrom-Gould procedure is a commonly recommended operative treatment for chronic ankle instability. Using standardized physician-based outcome scores, the results of this procedure have been uniformly excellent. Current scoring systems, however, do not adequately evaluate mechanical or functional instability. Therefore, outcome data may suggest greater success than is justified. Methods: A retrospective review was done of 73 patients who had isolated Brostrom-Gould repairs of the lateral ankle ligaments. The mean time to followup was 64 months. Both the AOFAS ankle-hindfoot score and the Short Form 36 (SF-36) were used to evaluate outcome. Results: The overall American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score was 95 of 100 points. Despite that, 17% of patients in the study had functional instability of the ankle that was not reflected in the AOFAS score. The mean physical component score of the SF-36 was 84% and reflected the presence of functional instability. Low correlations were found between the AOFAS ankle-hindfoot score and the SF-36 score. Conclusions: The current study identified a deficiency in the AOFAS score in evaluating functional ankle stability after the Brostrom-Gould procedure. A more meaningful analysis of outcomes can be expected using the SF-36 score. The data suggest that greater attention must be paid to functional rehabilitation after ankle stabilization surgery to obtain optimal outcome.