Chiari骨盆截骨术中外展肌张力对股骨头软骨生物力学影响的三维有限元分析

目的　探讨Chiari骨盆截骨术中外展肌力负荷对股骨头软骨的生物力学影响。方法　建立Chiari骨盆截骨术的髋关节三维有限元模型，应用非线性接触压力分析方法，观察不同的外展肌力负荷条件下关节软骨接触压力及软骨下骨应力分布。结果　Chiari术后关节软骨的接触压力和股骨头软骨下骨应力明显降低，接触面积明显增加。随着外展肌力负荷的降低，接触压力的重新分布更加明显。对应于原髋臼软骨的压力逐渐降低，新髋臼软骨的压力逐渐升高。股骨头软骨下骨应力也进一步降低。而术后关节软骨的接触面积改变不大。结论　外展肌力负荷所引起的生物力学改变在Chiari骨盆截骨术中起重要作用。

Mechanical Effect of the Hip Abductor Muscle on the Femoral Head after Chiari Pelvic Osteotomy Using Finite Element Method

Objective To investigate the effect of abductor load to the femoral head in the Chiari pelvic osteotomy by biomechanics. Methods The three-dimensional finite element hip models of Chiari pelvic osteotomy was constituted to observe the regularity of stress distribution according different abductor loads using the nonlinear contact analysis. Results It was found that the contact pressure and the peak stress after Chiari pelvic osteotomy decreased remarkably, but the contact area increased clearly. With the decreasing of the abductor loads, contact pressure and peak stress decreased correspondingly. And the contact pressure distribution transferred from the original acetabular area (pressure turning into low) to the new acetabular area (pressure turning into high) gradually. But the changes of the contact area were not significant after Chiari pelvic osteotomy corresponding to different abductor loads. Conclusion The biomechanics changes owing to abductor load plays an important role in Chiari pelvic osteotomy.