应用三维有限元分析正常站立位股骨近端结构生物力学特性

背景:目前股骨有限元研究较多,但以往的研究多集中于股骨外部的生物力学方面,关于股骨近端的生物力学研究较少.目的:建立股骨近端结构的三维有限元模型,对正常站立位下的股骨近端生物力学特性进行分析以指导临床工作.设计、时间及地点:三维有限元建模分析试验,于2008-12/2009-04在天津医科大学总医院完成.对象:天津医科大学总医院志愿者1名,男性,30岁,应用X射线排除股骨病变及损伤等情况.方法:在Mimics中直接读取符合Dicom 3.0标准的股骨近端原始CT数据,经阈值设定、区域增长及形态学操作等生成股骨初始3D模型,后期结合有限元软件ANSYS生成最终的三维有限元网格模型,然后在ANSYS中分别对应用Mimics得到的模型加载200 N的垂直载荷,观察股骨近端内部应力分布.主要观察指标:对模型施加200 N垂直载荷,观察股骨近端的Von mises应力分布.结果:应用Mimics和Ansys软件建立了股骨近端有限元模型,观察到股骨近端内部的应力分布,验证了结构与功能的对应关系.结论:应用Mimics可以建立更符合股骨近端机械结构和力学性质的三维有限元模型,据此模型得到的股骨近端力学特性分析结果更为可信,可以辅助指导临床应用.

Three-dimensional finite element analysis of biomechanical properties of proximal femoral structure under the normal standing position

BACKGROUND:At present,there are many established femoral finite element studies,but previous studies focused on femoral biomechanics of the outside are few.OBJECTIVE:To establish three-dimensional finite element model of structure of the proximal femur,and to analyze its biomechanics in normal standing position to provide reasonable evidence for clinical application.DESIGN,TIME AND SETTING:A three-dimensional finite element model analysis was performed in General Hospital of Tianjin Medical University from December 2008 to April 2009.PARTICIPANTS:One male volunteer aged 30 years was enrolled at General Hospital of Tianjin Medical University.Femur lesion or injury was excluded by means of X-ray.METHODS:The primitive femur CT data were adopted according to Dicom 3.0 standard in Mimics so as to obtain the primitive three-dimensional femur model which was established via threshold defining,region enlarging and morphological performing.The primitive model was remeshed and combined with ANSYS software to create a final finite-element model.The model obtained by using the Mimics was loaded with 200 N vertical loading to check out the difference of the stress distribution.MAIN OUTCOME MEASURES:Using 200 N as the external load in the vertical direction,the Vonmises stress distribution of the femur was detected.RESULTS:The applications of Mimics and Ansys software could create a finite element model of proximal femur.It was found that the correspondent relationship between stress and structure in proximal femur was verified.CONCLUSION:Mimics can build more three-dimensional finite element models in line with the proximal femoral mechanical structure and mechanical properties.The mechanical properties of the femur are more credible,and the results of the analysis support the clinical application of the guidance.