Gait dynamic stability assessment in a sagittal plane

FES assisted gait of paraplegic patients is inferior compared to a healthy subject. The difference can be observed in terms of speed, up-right balance, biomechanical energy consumption and generation of propulsion forces in the direction of walking. The authors believe that FES gait can be improved if converted into a semi-dynamically or dynamically stable gait. The walking mechanism is in dynamically stable state if mechanism can recover into a statically stable position without any action of supporting legs and/or reshaping the supporting area. In statically stable position the center of gravity (COG) projection on the ground (PCOG) is inside the supporting area. In this paper the relationship between COG movement and the supporting area is discussed as a criterion for dynamic stability assessment. Results are shown for two different modes of two-point and four-point gaits