Motion of the center of gravity of the body in clinical-evaluationof gait

The motion of the center of gravity during walking was analyzed in five hemiplegic subjects and eleven subjects affected by unilateral hip arthritis. In the hemiplegic subjects and 6 subjects with hip arthritis the transfer between kinetic and potential energy (with a passive pendular motion) was found to be 9-95% greater during the step performed on the affected limb ('pathological' step); as a consequence, the muscular work done during this step was 7-81% of the work done during the step performed on the sound limb ('normal' step). Qualitatively similar gait anomalies were recorded in all hemiplegic subjects with hypertonus of the paretic limb: these subjects had to lift the spastic limb as a whole during the normal step, with the consequence that the center of gravity was lifted 0.6-3 cm more than during the pathological step. In contrast, various motor patterns were found in patients with hip arthritis. During the pathological step the center of gravity reached a height 0.5-3 cm greater in 7 subjects, 1 cm smaller in one subject, and about the same height reached during the normal step in 3 subjects. This was consistent with the various motor deficits caused by hip arthritis.