The Effect Of An Ankle Brace On Peroneal Brevis Force During Lateral Landings

BACKGROUND: Ankle sprain is common among athletes engaging in jumping and landing movements such as playing volleyball. Wearing ankle braces during practice and game situations could protect the athletes. A novel TayCo (TC) brace was designed for use, external to the shoe, permitting sagittal plane motion while limiting frontal and transverse plane motion. It was unclear the degree to which the TC brace could effectively limit frontal plane motion during activities elevating ankle inversion such as lateral landings from a height. PURPOSE: To investigate the response of an ankle evertor (peroneal brevis) (PB) during lateral landings with a TC brace. It was hypothesized that the TC brace could reinforce the ankle’s frontal plane stability by reducing the need for more PB force. METHODS: On two separate occasions, six college students performed lateral droplandings from three heights (20 cm, 40 cm, and 60 cm) onto forceplates with/without a TC brace. Motion capture data (kinematic and ground reaction force) were used to drive subject-specific musculo-skeletal models during computer simulations in LifeMod (2010). Peak force of the right PB muscle was obtained and normalized to body weight (BW). Repeated measure ANOVAs were performed (Alpha = 0.05). RESULTS: The brace condition elicited 32%, 28%, and 39% less PB forces than the no-brace condition in 20 cm height (8.4 ± 2.5BW vs. 12.4 ± 3.7BW), 40 cm height (14.1 ± 3.4BW vs. 19.7 ± 4.8BW), and 60 cm height (12.5 ± 3.4BW vs. 20.4 ± 4.8BW), respectively. When the height was increased to 60 cm, the effect of the brace became more prominent (p = 0.026). Furthermore, when grouping all the heights into one analysis, the brace condition strongly showed less PB muscle force than the no-brace condition (p = 0.009). CONCLUSION: Although the findings were preliminary, it was evident that, overall, the TC brace effectively constrained the ankle, helping to prevent potentially harmful excessive inversion. This protective effect was demonstrated by a reduced load on the PB. Athletes who frequently face a high risk of ankle sprain during jumping and landing activities may benefit from wearing the TC braces during practices and competitions. Furthermore, military personnel who regularly perform high-impact landings, such as parachute landings, could also benefit from using TC braces.