Differences in Ankle Joint Force and Stabilization by Wearing Ankle Braces

Abstract

Physical therapists and doctors usually suggest patients with ankle sprain to use the ankle brace to protect their ankle joints. However, there are many types of ankle braces to choose, and the price range is quite large. Previous studies found that ankle brace may protect the ankle joint in terms of performance, range of motion, ground reaction force and muscle reaction. Yet, no study demonstrated the ankle joint force after wearing the ankle brace, especially for basic and advanced ankle braces. Therefore, our purpose of this study was to compare the differences between two kinds of ankle braces (soft ankle brace and lace-up ankle brace) in terms of stabilization and joint force. In this study, the motion analysis system and force plate were implemented to collect the data. Mathematical model was conducted to calculate the ankle joint force. The results showed that wearing lace-up ankle brace could increase the vertical ground reaction force and vertical ankle joint force, while decreased the medial-lateral (ML) ankle joint force. Compared to barefoot, wearing soft ankle brace or lace-up ankle brace were able to reduce the stabilization time in ML direction respectively. Although wearing soft ankle brace had the similar tendency as wearing lace-up ankle brace in stabilization time and ground reaction force, no statistical significant difference was noticed compared to barefoot. This study concluded that wearing either soft ankle brace or lace-up ankle brace would increase the ankle joint force in vertical direction to stabilize the ankle joint. Additionally, in ML direction, wearing lace-up ankle brace could significantly reduce the ankle joint force and quickly stabilize the ankle joint to get an effect of protecting ankle joint.