Three-dimensional finite element analyses on the transtibial residual limb and its prosthetic socket

Abstract

This paper presents a method for developing a nonlinear finite element model to analyze the load transfer between the transtibial residual limb and its prosthetic socket. The model was developed on the basis of three dimensional geometry of the residual limb, internal skeleton, soft liner and socket. Interface elements, were used to connect the skin and the liner to simulate the friction/slip boundary conditions. The analyses were performed in two steps to simulate the donning procedure and the load bearing situation. The model can be used to predict the pressures, shear stresses and slip between the residual limb and its socket under different external loads. Four models with different degrees of socket rectifications were analyzed. 通过建立三维非线性有限元模型来分析小腿假肢接受腔与残肢之间的载荷分布。此模型基于残肢 ,骨头 ,软套和接受腔的三维几何形状 ,考虑界面摩擦滑动条件和软组织的大变形等非线性因素。模型可以预测不同外载下残肢和接受腔之间的压力 ,剪切力和相对滑动情况。并分析了不同的接受腔形状对载荷分布的影响。