The effect of camber on shoulder muscle force in wheelchair propulsion

• Main Authors: Chao-Sian Shih, 施超獻
• Other Authors: Fong-Chin Su
• Format: Others
• Language: en_US
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/83630984329624981704

碩士 === 國立成功大學 === 醫學工程研究所碩博士班 === 96 === Wheelchair is the most common device for individuals with spinal cord injury. It is very easy to make the upper extremity get hurt especially shoulder joint when long term using. The camber of the rear wheel is a common characteristic in sports wheelchair, and it is an important factor in wheelchair propulsion. However, the effect of camber on muscle forces of upper extremities hasn’t been studied in previous studies. The object of this research is to exam the effects of camber on shoulder muscle forces using simulation method to analysis the muscle force in different kinds of camber angle. Twelve healthy subjects, who are unexperience wheelchair users, participated in this study. We use motion capture system to collect the kinematics data. An instrumented wheel with load cell was used to collect the force data. A previously built three dimensional shoulder musculoskeletal model was to calculate muscle forces of thirteen muscles around shoulder joint. In this research, participants were asked to propel wheelchair with 0˚, 9˚, and 15˚ rear wheel camber. Control the average wheelchair propulsion speed in 1m/s and 2m/s. The results indicated that when the speed increase, the activation of the muscle groups activating during propulsion phase increase and maximum muscle force also became larger. Muscle activation pattern did not change with different camber angle. Anterior deltoid had greater muscle force when we increase camber angle. The other usually have minimum in 9˚ or have no significant difference. By the research, we also can provide some information to the wheelchair user and designer. Help them to find some optimal balance between the wheelchair resistance and fraction of effective force.