不同股骨假体植入角度的髋关节表面置换术后股骨近端力学的有限元研究

Finite element analysis of hip resurfacing arthroplasty with different implant angles

目的探讨不同股骨假体植入角度对髋关节表面置换术后股骨近端力学变化的影响,为临床髋关节表面置换术股骨假体植入角度选择提供生物力学依据。方法采用16层螺旋CT扫描正常成人髋关节数据,建立植入角度为120°、125°、130°、135°、140°、145°的髋关节表面置换术后三维有限元分析模型,对所有模型施加人体缓慢行走时的载荷及约束,观察不同模型间股骨近端不同结构应力分布的变化。结果髋关节表面置换术后应力集中部位位于股骨金属假体-股骨骨质交界面处。随着股骨金属假体植入角度的增加,有效应力峰值呈逐渐减小趋势,135°～145°应力总体变化趋势不明显。结论骨质正常时,髋关节表面置换术的股骨金属假体植入适宜角度为135°～145°。

Objective To explore the biomechanical influences of femoral prosthesis implantation angle in 3-dimensional finite element （3D FE） models of Hip Resurfacing Arthroplasty （HRSA）. Methods Five different implant angles of HRSA 3D FE models were constructed based on the human anatomical data from multislice spiral CT. The femoral prosthesis implantation angle was 120°, 125°, 130°, 135°, 140°, and145° respectively. Pressure was added on each model to simulate status in normal walking. The patterns of the stress distribution on each model were analyzed. Results The stress concentration presented at head -neck junction part of the resurfaced femur. The maximum Von Mises stress value was decreased while increasing the femoral implant angles. However, the change was not obviously when the angle range from 135° to 145°. Conclusion The optimal angle of femoral prosthesis implantation in HRSA is from 135° to 145°.