Effect of dynamic loads on the interface pressure at the residual limb of a trans-tibial amputee

A quantitative understanding of the interface stress distribution between a prosthetic socket and the residual limb is fundamental to an optimal design of the prosthesis. Most previous finite element (FE) models are static ones whose results differ greatly from the real case. Based on the analysis of kinematic and dynamic properties during walking, a 3-D nonlinear finite element model was developed to analyze the effect of dynamic loads on the interface stress. The results show that interface pressures are mainly distributed at the patella tendon, the lateral tibia, the media tibia, and the popliteal depression regions, with the average peak interface pressure during walking being 1.15 times as the pressure for single-leg standing and 1.73 times as the pressure for double-leg standing. The interface pressure between the residual limb and the prosthetic socket was increased due to the dynamic loads so the dynamic effects during walking can not be ignored.