The effect of ankle braces on the prevention of dynamic forced ankle inversion.

Abstract

Athletes often employ prophylactic braces to reduce the risk of ankle injuries. Ankle braces do not significantly decrease the risk of forced inversion on a standardized one-footed jump landing. Controlled laboratory study. Fourteen healthy men with a mean age of 25.1 years were tested. Three braces, two semirigid (Aircast and Bledsoe) and one lace-up (Swede-O), were fitted to each subject. Forced dynamic ankle inversion of 24 degrees was to be resisted as the subjects landed on one foot with a force of two body weights on a stimulus presented randomly in 5 of 15 jump trial blocks onto a hard, level force plate. Subjects first completed 1 no-brace block of 5 trials to establish baseline performance, then 3 randomly ordered 15-trial blocks testing performance with each of the braces, and then finally a no-brace 5-trial block. The average no-brace success rate was 24%, which demonstrated the challenging nature of the task. All three braces increased the success rate (average, 44%); however, only the two semirigid braces proved to be significantly better than the unbraced state. This test holds promise for evaluating brace efficacy when landing with one foot unexpectedly on an object that acts to forcibly invert the ankle.