Instantaneous center of rotation by least square method.

In the design of the total replacement of the human joint, the joint center of rotation is often important. This paper describes an analytical technique to study joint kinematics, especially the instantaneous center of rotation. The empirical data for the analysis were obtained by the sonic digitizer system which works acoustically and electronically. As biomechanical applications of the technique, the elbow, the metacarpophalangeal, and wrist joints were studied.