Stride kinematics and knee joint kinetics of child amputee gait.

As a few quantitative data exist characterizing the gait of child lower extremity amputee (CLEA), this study provides such data by examining selected kinematic and kinetic variables during locomotion. Five unilateral CLEA were analyzed in an experimental design which comprised 3 different speeds of walking, 2 types of prosthetic feet (SACH-foot and an experimental CAPP-foot), and normal versus prosthetic limbs for a total of 104 trials. Cinematographic data and footprint information where used to quantify walking speed and uniplanar lower extremity angles. A rigid-body, linked model was used to evaluate the extent and range to thigh and leg motion and moments of force at the knee joint. The kinematic and kinetic characteristics of CLEA gait were affected significantly by variations in walking speed. Stride length, step length, and walking velocity decreased and stride width increased when the children used the experimental foot component; as speed of walking increased, stride length and step length increased with both prosthetic feet. Foot angles increased with walking velocity except for fast walking with the experimental foot component. Joint angles were significantly different between the normal and prosthetic limb. The only significant limb angle differences between the 2 prosthetic feet were in maximum hip flexion and the total range of thigh movement; the experimental foot elicited less hip flexion and and smaller range of thigh movement.