An investigation of kinematic and kinetic variables for the description of prosthetic gait using the ENOCH system

Abstract

Gait patterns, joint angles, floor reaction forces and joint moments during walking were investigated for normal subjects and above-knee and below-knee amputees. The investigation showed that the hip-knee angle diagram as well as different symmetry diagrams (e.g. left knee angle versus right knee angle) provide an easily interpreted means of evaluating abnormalities in the gait pattern. It was further concluded that a combined gait pattern-force vector diagram is valuable for the evaluation of the joint moments. Floor reaction forces and muscular moments at the joints were also included in the analysis. The joint moments at the knee were quite different for both above-knee and below-knee amputees as compared to the normal subjects. Some interesting trends were also found concerning the knee stability of the amputees. A system called ENOCH was used for the measurement and analysis. This system consists of a minicomputer connected on-line to equipment for measurement of displacement (Selspot) and floor reaction forces (Kistler). A graphic computer terminal (Tektronix) was used for the result presentation.