Effects of Materials of Wrist Guard and Arrest Strategies on Impact Force during Forward Falls

• Main Authors: Min-hsien Cho, 卓旻賢
• Other Authors: Shu-zon Lou
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/83993177521368473259

碩士 === 朝陽科技大學 === 工業工程與管理系碩士班 === 93 === Wrist guards are one of the protective devices widely used for preventing from a distal radius fracture during in-line skating and snowboard-related activities. However, more than half of the people wearing wrist guards sustained a fracture of the wrist on forward falls. The purpose of this study is to evaluate the three factors, materials of wrist guard, fall heights and arrest strategies on impact force during forward fall by the biomechanical experiments. Ten physically healthy male subjects volunteered for this investigation. None had ever suffered from upper extremity injuries or disorders. Trajection of human motion, ground reaction force (GRF) and acceleration (ACC) on the palm were collected using Motion Analysis System (VICON 460 and ATMI) from a self-established releasing system. Joint motion and force, GRF and ACC with respect to time and frequency domains were then analyzed for effects of three independent parameters on impact force during forward falls. The first parameter is the material of wrist guard including bare hand (Bare), common wrist guard (Guard), wrist guard with insole outside (Out) and wrist guard removing splint below with insole (In). The second parameter is the arrest strategy including elbow extended and flexed. The third parameter is fall height including 4cm and 8 cm above force plate. The results of this study were as follows. The impact force, loading rate, peak value of ACC, and peak joint forces of elbow and abduction moment significantly increased as the increase of fall height. The strategy of elbow flexed could attenuate the peak GRF and delay the time of peak impact force. The extension moment of elbow in elbow flexied significantly increased than that in elbow extended. In the effect of materials, the GRF, loading rate and peak value of ACC with Out and In decreased significantly than those with Bare and Guard. The conclusion is that lower falling height, using wrist guard with a compliant pad (In or Out) and using the strategy of elbow flexed will decrease the impact force and the risk of injury of upper extremity.