AN ALTERNATIVE MODEL OF THE LOWER-EXTREMITY DURING LOCOMOTION

An alternative to the Iterative Newton-Euler or linked segment model w as developed to compute lower extremity joint moments using the mechan ics of the double pendulum. The double pendulum model equations were a pplied to both the swing and stance phases of locomotion. Both the Ite rative Newton-Euler and double pendulum models computed virtually iden tical joint moment data over the entire stride cycle. The double pendu lum equations, however, also included terms for other mechanical facto rs acting on limb segments, namely hip acceleration and segment angula r velocities and accelerations. Thus, the exact manners in which the l ower extremity segments interacted with each other could be quantified throughout the gait cycle. The linear acceleration of the hip and the angular acceleration of the thigh played comparable roles to muscular actions during both swing and stance.