目的 利用有限元方法研究髋残肢在支撑阶段与髋离断假肢接受腔生机界面的力学特性,为优化、设计髋接受腔结构提供理论依据,为评估髋接受腔舒适度提供研究基础。方法 根据患者残肢的CT扫描模型,采用逆向建模的方式,三维重建骨骼、软组织以及接受腔的模型。利用有限元分析方法研究站立状态下的残肢-髋接受腔界面正应力及剪切应力的分布情况,并通过设计压力采集模块系统进行验证。结果 残肢与髋接受腔界面应力主要分布在腰部和残肢底部,位于残肢其余区域的界面应力则分布较为均匀。有限元计算结果和压力采集模块系统测量结果有较好的符合。结论 为能较好实现髋接受腔功能传递性和安全舒适性,需要充分考虑残肢腰部和底部的受力,残肢与接受腔的配合度。
Objective Application of finite element analysis (FEA) method to study the mechanical properties of the interface between hip residual limb and hip socket during the stance phase, in order to provide a theoretical basis for the structure optimization and design of the hip socket and also provide a research basis for the comfort evaluation of the hip socket. Methods According to the CT scan images of the patient"s residual limb, the model of bone, soft tissue and socket was reconstructed by reverse modeling. Application of FEA method to analyze the distribution of normal stress and shear stress of the interface between the hip residual limb and hip socket and design a pressure acquisition module system to verify the stress distribution condition. Results The interfacial stress between the hip residual and hip socket was mainly distributed in the waist and the bottom of the residual, and the interfacial stress was more evenly distributed in the rest of the residual. The results of finite element calculation are in good agreement with the system measurement results of pressure acquisition module. Conclusions In order to improve force transfer and safety and comfort of the hip socket, it is necessary to fully consider the stress condition of the waist and bottom of the residual limb and the coordination degree between the residual limb and the hip socket.