【摘要】 采用接触非线性有限元模型,分析在生理载荷下一个完整步态中人工髋关节的微动规律.通过CT图像重建出完整股骨三维CAD模型,按照手术要求模拟关节植入,采用面-面模型构造出人工髋关节置换术(THR)后假体与股骨接触非线性有限元模型.按照不同步态事件下髋、膝关节力作为载荷步进行加载计算.计算结果分析表明:一个步态下人工髋关节的微动在0~25μm,微动形式分别为沿矢状轴和冠状轴的旋转运动.造成长期效应下的人工髋关节无菌松动的主要原因是关节的微动.更多还原

【Abstract】 The purpose of this study is to explore the micromotion characteristics of prosthesis in gait cycle under physiological load.An anatomical CAD model of total femur was generated from CT image.The prosthesis was virtually implanted into the femur model with surgically position to form a nonlinear FEA contact model.Gait cycle was divided into 8 gait event as load step.The FEA analysis shows the micromotions of prosthesis are two kinds of rotation around the frontal axis and the sagittal axis respectively,the magnitude of the bone-implant relative micromotion range in 25 μm in one gait cycle.The micromotion is the main cause which will lead to long-term aseptic loosening of prosthesis.更多还原