Effects of Bracing on Isokinetic Torque for the Chronically Unstable Ankle
Because the effects of bracing on dynamic torque production are unknown, the purpose of this study was to determine the effects of flexible and semirigid braces on isokinetic torque production at varying velocities produced by the invertor and evertor muscles for the chronically unstable ankle. Ten healthy and 14 chronically unstable ankles were tested, with a repeated-measures design including joint motion (inversion, eversion), muscle contraction type (concentric, eccentric), brace condition (unbraced, flexible, semirigid), and velocity (60, 120, 180, 240°/s). Multiple ANOVAs with repeated-measures and Bonferroni-adjusted comparisons were performed. Results showed that the chronically unstable ankle was significantly weaker than the healthy ankle, regardless of muscle contraction type or joint motion, and that bracing did not deter the muscles' ability to produce peak torque either concentrically or eccentrically. The chronically unstable ankle requires enhanced strengthening, particularly eccentrically and at higher, more functional velocities. Bracing can reduce or prevent injury to the ankle without deterring torque production.