A novel way of measuring ankle stability after functional activity

Kaminski, Thomas W.Context: Ankle sprains make up 85% of injuries to the foot and ankle and up to 70% of cases may develop ankle instability (AI). Functional and mechanical insufficiencies contribute to AI. Taping and bracing have become common practices, to prevent initial and recurrent ankle sprains. They are intended to restrict excessive ankle joint motion; however, their effectiveness during sport activity is inconclusive. Objective: To compare differences in laxity at the ankle in taped and braced conditions, in individuals with and without ankle instability, before and after exercise. Design: Pre-test post-test design with control group. Setting: Human Performance Laboratory. Participants: Twenty-four participants (20.6±1.6yrs, 173.6±8.3cm, 72.8±12.2kg) were placed into one of three groups; ankle instability, previous sprain with no instability, or no previous sprain. Intervention(s): Ankle laxity was assessed on each subject to test the effect of an ankle taping and bracing from pre- to post- exercise. A 20-minute exercise protocol was performed utilizing each of the external prophylactic support (EPS) conditions (tape, brace, control/none). Main Outcome Measure(s): Ankle laxity (anterior displacement and inversion-eversion rotation) was measured using an ankle arthrometer under three conditions and in three groups. A repeated measures ANOVA was utilized to analyze differences between the groups and within EPS type and pre-post exercise. Results: Taping and bracing both restricted anterior displacement, inversion and eversion rotation at pre and post exercise (p<.05). Tape provided greater restriction post exercise in inversion and eversion rotation (p<.05). The ankle instability group had a significantly greater anterior displacement post exercise after removal of the brace. Conclusions: Ankle taping provides more mechanical restriction at the ankle, compared to the bracing. However, both provided a significant amount of restriction after 20 minutes of exercise when compared to measurements without taping or bracing. It appears that EPS may be effective in providing mechanical support to individuals involved in short-term exercise bouts.University of Delaware, Department of Exercise ScienceM.S