小腿残肢与接受腔的非线性有限元分析  

Non-Linear Finite Element Analysis of Trans-Tibial Residual Limb and Prosthetic Socket

作　　者：杨海艳 吴晓[1] 冯晓华 YANG Haiyan;WU Xiao;FENG Xiaohua(School of Mechanical Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]西南交通大学机械工程学院

出　　处：《医用生物力学》2019年第3期232-236,共5页Journal of Medical Biomechanics

摘　　要：目的研究残肢与接受腔生机界面力学特性及残端应力情况,为设计和优化小腿接受腔结构、提高其佩戴舒适性提供理论依据。方法针对释压稳定(compression-release stabilization,CRS)接受腔,采用有限元软件ABAQUS分析残肢与CRS接受腔界面应力分布情况,软组织采用非线性超弹性材料Mooney-Rivlin本构模型,得到静止站立中期残肢与CRS接受腔接触界面正应力和剪切应力分布情况,并相应建立髌韧带承重(patellar tendon bearing,PTB)小腿接受腔三维有限元模型,将两者结果进行比较。结果残肢与CRS接受腔界面应力主要分布在胫骨内侧、胫骨外侧和后肌群等承重区,与PTB接受腔模型主要受力区域相似,CRS接受腔残肢末端平均界面应力较PTB接受腔高19kPa。结论 CRS接受腔具有较好的透气性且应力分布较合理,接受腔形状的不同可改变残肢与接受腔生机界面应力分布,优化其设计有助于提高假肢穿戴舒适性。Objective To study the load transfer mechanics between residual limb and prosthetic socket, as well as stress distributions below the residual limb, so as to provide a theoretical basis for designing and optimizing of prosthetic socket and improving the wearing comfort. Methods Aiming at compression-release stabilization(CRS), the finite element software ABAQUS was used to analyze the stress distribution at the interface between the residual limb and CRS socket. The soft tissues were defined using the Mooney-Rivlin function. The interface pressures and shear stresses between the residual limb and CRS socket during mid-stance were obtained. A three-dimensional finite element model of the patellar tendon bearing(PTB) socket was established, and the results were compared. Results The interface pressures between the residual limb and CRS socket were mainly distributed at lateral tibia, media tibia and popliteal depression regions, which were similar to the main force regions of PTB socket. The mean interface pressures on the end of stump for CRS socket was increased by 19 kPa over PTB socket. Conclusions CRS socket had better breathability and reasonable stress distributions. The stress distribution of biomechanical interface was different due to the different shapes of socket. Therefore, the optimization of prosthetic socket can help to improve the wearing comfort of prosthetic limbs.

关 键 词：释压稳定接受腔 非线性有限元分析 超弹性材料 界面应力 

分 类 号：R318.01[医药卫生—生物医学工程]