Influence of metatarsophalangeal joint flexion on gait characteristics

The purpose is to investigate the action of metatarsoophalangeal (MP) joint flexion on gait pattern and the responses of subjects when their MP joints are constrained. The study will be useful for physical therapy, prosthesis designing and gait planning for biped robot. Five healthy young subjects were instructed to walk at their preferred speed on a level pathway with and without MP joint flexion. Differences were seen between the peak angular displacements and velocities of each joint for subjects with and without constraints. When the MP joints were constrained, the movement of other joints was modified in a multi-joint coordination motion compensatory strategy involving the hip, knee and ankle joints. The knee and ankle joints provided the most significant compensation with some additional effect from the back. The compensation strategies enable the subjects with constrained MP joints to walk in a nearly normal gait with an average speed 94.8% of normal and an average stride length 95.5% of normal.