The effect of an ankle orthosis on ankle range of motion and performance.

Ankle joint orthoses are used for rehabilitation and/or prevention of ankle sprains. The purpose of this study was to determine the effect of the Malleoloc ankle joint orthosis on active and passive range of motion reduction and on a jumping and a figure-eight running test. Twelve subjects with a history of inversion ankle sprain and documented increased anterior translation in a drawer test participated in the study. Active and passive range of motion for inversion was determined with and without the orthosis and pre- and post-exercise. Additionally, performance tests for figure-eight running and jumping were administered. The results showed that the tested orthosis 1) restricted the active range of motion and passive inversion substantially, 2) reduced the other movement degrees of freedom only minimally, 3) provided the same movement restriction before and after exercise, and 4) did not affect performance. The Malleoloc ankle joint orthoses can, therefore, restrict ankle joint motion without affecting performance negatively.