| Ankle sprains are among the most common injuries in sports. The majority involve the lateral ligaments of the ankle following a rapid inversion of the weight bearing joint. The ability of prophylactic stabilization to minimize the impact of these forces has been studied extensively. An innovative device designed to evoke a 20° inversion perturbation was used to demonstrate that application of ankle prophylaxis is effective in improving muscular response in healthy individuals. Forty one volunteers (21 males, 20 females) underwent EMG analysis of the peroneus longus (PL) and tibialis anterior (TA), measuring reflex latency (RL) and time to peak amplitude (TPA) while performing a dynamic task. Data were collected while subjects were fitted with two types of ankle braces (lace-up and semi-rigid) and standard closed basketweave ankle taping, each compared with a no support control. In addition, a comparison of PL and TA was conducted to determine muscle differences on measures of RL and TPA. Significantly shorter RL in the PL were observed in the lace-up and semi rigid brace conditions compared to the no brace (p = 0.004, p < 0.001) control. Similarly, the semi-rigid brace was significantly shorter than the tape (p < 0.001) condition. In the TA, RL were significantly shorter for the laceup than the no brace (p < 0.008) control. TPA values were significantly shorter for the lace-up and semi rigid brace conditions in the TA compared to the no brace (p = 0.007, p = 0.001) control; and the semi-rigid brace TPA was significantly shorter than tape (p < 0.001). No significant differences were observed in either RL or TPA measurements (p > 0.05) between the PL and TA. The dynamic task in this study better replicates the conditions which often precipitate ankle injury. Results indicate the application of ankle support may be beneficial in heightening the sensitivity of dynamic restraints, thus minimizing the effects of a rapid inversion mechanism. In particular, the lace-up and semi-rigid braces appeared to be the most effective in hastening muscular responses observed during a dynamic task. The implications for these findings would be of particular interest to the clinician when recommending the type of prophylactic support to be employed during sport activity. |
