Deficits in detection of inversion and eversion movements among subjects with recurrent ankle sprains

Study Design: Observational cross-sectional design. Objectives: To determine whether a deficit exists in the ability to perceive inversion and eversion movements among subjects with recurrent ankle sprains. Background: Although unproven, ankle sprains are thought to recur because proprioception is impaired subsequent to the original sprain. Proprioception has been widely studied, however, the specific property of movement, perception has not been rigorously examined for both inversion and eversion movements. Methods and Measures: The ability to perceive passive inversion and eversion movements imposed at the relaxed ankle was measured in 39 subjects with recurrent ankle sprains (sprainers) and 30 subjects with no history of ankle injury (controls) by an assessor masked to subject group. The 70% detection level for movement perception was determined for 3 velocities, 0.1degrees/s, 0.5degrees/s, and 2.5degrees/s, tested in random order. Results: The 70% detection level for inversion and eversion movements improved with increasing velocity in both groups. At all velocities, the 70% detection level for movements imposed at the ankle of the sprainers was significantly worse than for controls. Conclusions: Perception of passive inversion and eversion movements imposed at the ankle was impaired in subjects with recurrent ankle sprains. The impairment was evident at the 3 velocities tested, 0.1degrees/s, 0.5degrees/s, and 2.5degrees/s.