多段式骨植入体周围骨应力分布的三维有限元分析

针对植入性下肢假肢采用传统的一段式骨植入体，长期植入下由于对植入体周围的骨产生应力屏蔽效应继而引起骨质疏松，从而导致植入体松动、脱落而失效的问题,设计了一种新型的多段式结构的植入体。基于人体CT扫描数据建立了相关股骨和骨内植入体模型，针对低、中和高位下肢截肢步行最大生理载荷情况下，采用三维有限元分析方法，对新设计周围骨应力进行了分析研究，并与传统一段式骨植入体和健康自然骨的应力分布情况进行了比较。结果表明新型植入体植入后相比于一段式应力屏蔽和集中的程度得到了有效减轻，与自然状态下骨的应力较为接近，低、中位截肢下应用较好，高位下应力集中较明显，并能保持其在体内的稳定性。

3D FEA of Bone Stress Around Multi-part Osseointegrated Implant

Faced with the problem of the loose and extrusion, and then the malfimction of the osseointegrated implant for percutaneous osseointegrated artificial lower limb attachment after long-time of use caused by stress shielding, which occurred always around traditional one part implant, a new type of implant-multi-part implant was developed. Based on CT data and under the maximal load during a normal walking cycle, 3D finite element analysis was carried out to analyze the stress of bone around the new implant in three cases of distally tnmcated femur at high-position,middle-position and lowposition. Results showed that stress shielding and stress concentration under the new type of implant are reduced effectively compared with the traditional one-part implant, and the stress distribution is much close to the natural bone. Application for distally truncated femur at middle-position and low-position was much better, while stress concentration was marked at high-position. Meanwhile, the stability in vivo can also be maintained with the multi-part implant. The new implant can markedly reduce the adverse effect of stress shielding, which is promising applied for prosthetic limb.