Biomechanics of Ankle Instability. Part 1: Reaction Time to Simulated Ankle Sprain.

Mitchell, Andrew; Dyson, Rosemary; Hale, Tudor; Abraham, Corinne

The purpose of this study was to test the hypothesis that ankles with functional instability will demonstrate slower muscular reaction times than their contralateral stable ankle (SA) and stable healthy controls to a simulated nonpathological ankle sprain mechanism.  Nineteen male volunteers with a history of unilateral ankle sprain and functional ankle instability (FAI) and 19 healthy male controls performed reaction time tests on a purpose-built platform that simulated a nonpathological combined inversion/plantarflexion ankle sprain mechanism.  Results demonstrate a deficit (slower reaction time) in ankles with FAI when acting in support and when exposed to a simulated sprain compared to stable healthy controls. As a result of slower reaction times, acting to support the UA may put the contralateral SA at an increased risk of ankle sprain.

Rehabilitation of a lateral ankle sprain should include strengthening the evertors (peroneals and EDL) at the subtalar joint and the dorsiflexors (TA and EDL) at the talocrural joint.

Medicine & Science in Sports & Exercise, 2008,    40(8), 1515-1521

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