Hip Hiking Gait Improvement with Electrohydraulic Robotic Knee: Preliminary Results

Individuals with Transfemoral Amputation (TFA) usually exhibit hip hiking walking with passive prostheses due to insufficient knee flexion. Powered knee prostheses can provide net-positive energy in the knee joint with improved gait symmetry. However, their effects on improving hip hiking are not well understood. This study investigates residual hip hiking through walking experiments using a robotic transfemoral prosthesis that can provide swing assistance. Different levels of assistive flexion torque were provided during the pre-swing and the mid-swing (no assistance, low assistance, medium assistance, high assistance). The kinematic and electromyographic (EMG) results indicate that with the increasing assistive torque level applied, the residual hip hiking was improved. The results preliminarily demonstrate the positive effect of knee flexion assistance on hip hiking improvement.