基于X线片与模板的股骨柄假体生物力学评价

Biomechanics evaluation of femoral prothesis stem based on X ray and template

目的对4组与股骨匹配的股骨柄假体进行生物力学的评价,寻找与正常股骨上力学分布最为接近的股骨柄假体。方法在Matlab中导入股骨近端X线正位片及4组股骨-股骨柄假体模板的bmp格式的图像文件,分别提取股骨、带假体模板的股骨二维轮廓数据,利用ANSYS软件建立股骨、股骨-股骨柄几何模型及二维非线性有限元模型,负荷加载后对股骨近端的应力分布进行分析、比较。结果假体置入后股骨上的力学分布与正常股骨有较大的差异,但在4组股骨柄假体中,终有一种假体其在股骨上应力大小及分布情况与正常股骨最为接近,而这种假体相对于此股骨来说其生物力学性能为最优。结论通过基于X线片与模板的股骨柄假体生物力学的分析比较,可对股骨柄假体的生物力学性能作出评价,为假体的优化选择提供依据。

Object To evaluate the biomechanics of several groups of femoral prothesis stems matched with a femur ,and get a stem which mechanics distribution neady to normal femur from these stems. Methods The image files with bmp format of the proximal femur X ray and four groups femur- prothesis templat matched with the femur were introduced ,and the bi-dimension contour data of femur and femur matched with the template were extracted respectively ,we made use of the sofe of ANSYS to establish the model of geometncal and bi-dimesion nonlierarity Finite Element including femur and femur-femoral stem, the condition of stress distribution in proximal femur was analysised and compared by loading. Results After the stem was inset, the stress distribution and value in proximal femur were different from normal femurobviously, but in four groups stems ,there was a stem which stress distribution and value in proximal femur nearly to normal femur at last and the stem＇s biomechanics property was superior to the others＇ in the femur. Conclusion By analying and comparing the biomechanics of the femoral prothesis based on X-ray and template, the property of biomechanics of femoral prothesis has been evaluated to offer basis for super-selection prothesis.