膝下残肢界面应力准动态有限元模型研究  

The investigation on a quasi-dynamic finite element model to predict interface pressure on below-knee residual limb

作　　者：贾晓红[1] 方丽丹[1] 张明[2] 王人成[1] 

机构地区：[1]清华大学摩擦学国家重点实验室智能与生物机械分室,北京100084 [2]香港理工大学复康科技中心

出　　处：《中国康复医学杂志》2005年第7期484-486,共3页Chinese Journal of Rehabilitation Medicine

基　　金：国家自然科学基金资助项目(50305013)

摘　　要：目的:为计算小腿截肢患者行走过程中残肢和接受腔之间的界面压力。方法:根据残肢、骨骼和假肢接受腔的真实几何形状建立了准动态有限元模型,采用了自动面面接触模型模拟皮肤和接受腔衬套之间的边界摩擦和滑动,并在考虑行走过程中外力和惯性载荷的同时,考虑了膝关节刚体位移和残肢弹性变形之间的耦合。结果:对一个步态周期内的残肢界面压力进行了仿真计算,结果表明界面压力主要分布在髌韧带区、腘窝区、胫骨内外侧。在站立相,除髌韧带区外,其他区域的压力具有与地面反力相似的变化规律。结论:本文所建立的准动态模型考虑了患者行走过程中膝关节位移,更接近于人体真实运动,能够用于假肢接受腔界面特性的预测和现代假肢的数字化设计。Objective：To predict the inteface pressure between residual limb and prosthetic socket for below-knee （BK） amputees during walking.Method：A quasi-dynamic finite element model was built based on the actual geometry. of residual limb, internal bones and socket liner. To simulate the friction/slip boundary conditions between the skin and liner, the automated surface-to-surface contact was used. Not only the variable external loads and material inertia but also the coupling between the large rigid displacement of knee joint and small elastic deformation of residual limb were considered.Result： The interface pressure was predicted in one gait cycle. The high pressures fell over popliteal depression, middle patella tendon, lateral tibia and medial tibia regions. The interface pressures except for the one at patella tendon region had the similar double-peaked waveform shape of ground reaction force in stance phase. Conclusion：The quasi-dynamic finite element model built in this paper can almost really simulate the motion of knee joint during walking, it can be used for prediction of interface biomeehanical property on residual limb in a prosthetic socket and digital design of modern prosthesis.

关 键 词：界面压力 有限元分析 似肢接受腔 膝下截肢 

分 类 号：R318.0[医药卫生—生物医学工程]