The effects of wearing an ankle stabilizing orthosis (ASO) ankle brace on ankle joints kinetics and kinematics during a basketball rebounding task

Abstract

Following an ankle injury, athletes sometimes brace the injured ankle in hopes of minimizing the likelihood of suffering a recurring injury. This study aims to evaluate the effects of wearing an Ankle Stabilizing Orthosis (ASO) ankle brace unilaterally on the dominant side on bilateral ankle joint kinetics and kinematics and peroneus longus EMG activity. Since a significant proportion of ankle injuries in basketball occur during rebounding, data was collected during a simulated rebounding task. Rebounding is defined as the act of retrieving a missed shot attempt. Subjects oftentimes jump vertically to acquire the basketball as it rebounds from the backboard or rim. Sixteen subjects participated in the study (11 males, 5 females; mean age = 26.94 years, SD = 5.32; mean height 1.72 m, SD = 0.08; mean weight 73.95 kg, SD = 13.68). Participants completed the rebounding task in braced (ASO) and unbraced (UB) conditions. Ankle and foot inversion angles, ankle inversion moments and peroneus longus EMG activity were recorded and analysed to determine the effects of wearing an ankle brace unilaterally. In the dominant limb, when compared to UB, ASO reduced ankle and foot inversion, and increased ankle inversion moments. No significant differences were observed in peroneus longus EMG activity. In the non-dominant limb, no significant differences were observed for any of the parameters. These results suggest that wearing an ASO ankle brace on the dominant ankle reduces maximum ankle and foot inversion angles without posing an increased risk to the unbraced leg. However, the increased ankle inversion moments in the braced ankle suggest that there are adjustments regarding force distribution, perhaps due to the restricted range of motion.