Biomechanical evaluation of a prototype foot/ankle prosthesis

The authors report on their pilot evaluation of a prototype foot/ankle prosthesis. This prototype has been designed and fabricated with the intention of providing decreased ankle joint stiffness during the middle portion of the stance phase of gait, and increased (i.e., more normal) knee range of motion during stance. The authors' evaluation involved fitting the existing prototype foot/ankle prosthesis, as well as a traditional Solid Ankle Cushioned Heel (SACH) foot, to a reasonably healthy volunteer below-knee (BK) amputee, and then measuring the individual's lower extremity joint kinematics and kinetics. These measurements permitted direct comparison of prosthetic ankle joint stiffness, involved side knee joint range of motion, as well as prosthetic ankle joint moment and power.