【摘要】 基于CT扫描数据,针对低、中和高位下肢截肢步行最大生理载荷情况下,建立植入性下肢骨植入体及人体股骨三维有限元分析模型,计算结果表明:假肢的最大应力位于骨植入体外力传递杆靠近残肢残端,是假肢周期性载荷的疲劳破坏点;随截肢部位上移,股骨内应力最大值迅速增大;在植入体与股骨接触部位,存在严重的应力屏蔽,应力集中的两个区域分布在植入体末端和股骨四分之三处,可能导致骨质废用性和病理性吸收,影响假肢中长期使用寿命。本研究还表明,股骨的自然曲率对骨内应力分布有较大的影响,是不能忽略的因素。本文所获结果可为植入假肢的设计研究提供依据。更多还原

【Abstract】 Using the CT data,we have constructed the finite element models of human femur distally amputated at high-position,middle-position and low-position,along with distally osseointegrated implant under the maximal load during a normal walking cycle.Results of finite element analysis revealed:the maximal stress of implant is produced near the exit of the amputated limb,where the fatigue breakpoint caused by cyclic stress would take place.With the ascending of truncated position,the peri-implant interfacial stress of bone increases.There is severe stress-shielding at the bone-implant interface,and there is concentration of stress at the end of implant and at the 3/4 point of femur,which would lead to bone loss and bone resorption and would shorten the longevity of implant.The results also showed that the curvature of natural bone has notable effect on the stress distribution,which should not be neglected.These data may provide reliable reference for the design and research of osseointegarted artificial limb.更多还原