| Lateral ankle sprains are among the most common orthopedic injuries and often lead to ankle instability; a condition characterized by pain, weakness, and most problematically, recurrent ankle sprains. Ankle Instability is generally attributed to neuromuscular and proprioceptive deficits; however the pathoetiology behind the condition remains unknown. This work aimed to further understand preparatory and reactive neuromuscular control strategies in individuals with ankle instability (AI group), individuals who have suffered a lateral ankle sprain, but did not develop ankle instability (LAS group), and uninjured controls (CON group) via the use of a novel ankle supinating device, which was created to simulate the mechanism of a lateral ankle sprain during landing. We hypothesize that individuals with ankle instability would demonstrate altered preparatory and reactive neuromuscular control relative to the other two groups, which may predispose them to episodes of their ankle giving way. Contrary to our hypotheses, the AI group was not significantly different than the CON group. In this work, it was the LAS group that differed significantly in their preparatory neuromuscular control patterns from the other two groups, specifically demonstrating a significantly increased TA activation prior to landing. While contrary to traditional logic, we speculate that this is a neuromuscular control pattern in LAS subjects that allows them to control dynamic ankle stability after damage to the lateral ankle ligaments; including controlled kinematics and/or force attenuation. While the device used effectively mimicked the mechanism of a lateral ankle sprain in a safe environment, there were not statistically significant differences in reactive neuromuscular control between the groups. Future work should aim to better categorize individuals with ankle instability, as well as monitor the role of the entire lower extremity in controlling dynamic stability at the ankle joint. Furthermore, future studies should aim to evaluate individuals who have suffered a lateral ankle sprain, but did not develop ankle instability. These individuals may hold the key to understanding neuromuscular control strategies in ankle instability, which could lead to the development of more appropriate treatment and rehabilitation paradigms to reduce the incidence of ankle instability. |
