The effect of external ankle support in chronic lateral ankle joint instability. An electromyographic study.

We examined the effect of ankle taping on ankle joint stability by measuring mechanical stability using standardized stress radiographs. Anterior talar translation and talar tilt, both with and without ankle tape, were examined. The reduction of anterior talar translation and talar tilt with tape as compared to without tape was insignificant. The reaction time of the peroneus muscles was measured by electromyographic signal after a simulated ankle sprain on a tilting trapdoor. The reaction time was significantly slower in the unstable ankles of 20 athletes with unilateral ankle instability than in the stable contralateral ankles. With tape, the reaction time was significantly shortened, although not back to normal. The greatest improvement in reaction time was achieved in ankles with the highest degree of mechanical instability. Thus, the mechanism behind the function of ankle tape may be to restrict the extremes of ankle motion and to help shorten the reaction time of the peroneus muscles by affecting the proprioceptive function of the ankle.