BIOMECHANICAL ANALYSIS IN ARM PROSTHETICS 􀂱 OBJECTIFYING OF FUNCTIONAL ADVANTAGES OFFERED BY WRIST FLEXION

Abstract

By means of flexion wrists the functionality of prosthetic fittings for upper extremities can be improved significantly. Objects can be manipulated more favourably. Furthermore an optimized gripping position allows an improved body posture. Reaching objects or other dynamic processes are essential in amputee􀂶s ADL􀂶s. The path of motions influences the whole extremity in a physiological manner. Biomechanical measuring results demonstrate the advantages in movement by individual hand positioning. Measurements were conducted by means of an optoelectronic camera system for recording motion kinematics (VICON 460, VICONPEAK Oxford, GB). The subjects were fitted with myoelectric arm prostheses and performed predefined motion tests. Position of flexion angle and hand rotation varied systematically. Depending on the posture of the hand the optimization of certain motion patterns could be proved. Repeating action is supported and can be performed more persistently. Some activities confirmed the significance of optimized interaction between wrist rotation and flexion.