Work and power in gait of stroke patients.

Biomechanical analysis of the work and power patterns involved in gait provides insight into the nature of gait deficits and suggests methods for improvement. The purpose of this study was to describe the work and power characteristics during gait for both limbs of hemiplegic patients, and to determine the work and power variables related to self-selected speeds of walking. The gait of 30 ambulatory adults between the ages of 47 and 79 years was studied using two-dimensional cinematography and force-plate data in a link-segment model. About 40% of the positive work required for walking was performed by the muscles of the affected side. Major contributors were the ankle plantar flexors, hip flexors, and hip extensors. The results suggest interdependence between the limbs and between muscle groups of the same limb; a need for further research is indicated.