A new hybrid spring brake orthosis for controlling hip and knee flexion in the swing phase

It is proposed that active contraction of muscles might be artificially replaced by a spring brake orthosis (SBO) to provide near-natural knee and hip swing phase trajectories for gait in spinal cord injured subjects. The SBO is a new gait restoration system in which stored spring elastic energy and potential energy of limb segments are utilized to aid gait. It is also shown that hip flexion can be produced without the need for withdrawal reflex, hip flexor stimulus or any mechanical actuator at the hip. A hip flexion angle of 21 degrees was achieved by a nonimpaired subject wearing a prototype orthosis.