人工髋臼接触力学特性的有限元分析

目的 考察人工超高分子量聚乙烯髋关节臼的接触力学特性.方法 建立人工髋臼模型,对模型进行网格划分,在接触区域建立接触对,按真实人体关节对模型进行边界条件的设定后进行有限元接触力学分析.对不同条件下(摩擦系数0～0.25,髋臼厚度6～12 mm,髋臼直径26～32 mm)的髋臼分别进行步态分析.结果 计算结果显示压缩变形量在接触面摩擦系数增大、髋臼直径增加情况下均呈现下降趋势.接触层厚及接触面积受髋臼厚度的影响在不同尺寸处体现不同的特性,接触面积和层厚对于植入假体的稳定性及磨粒的产生有重要影响.结论 综合考虑两者的作用效果认为7～9 mm厚的髋臼表现效果较好.

A Contact Mechanics Characteristic Analysis of Artificial Acetabulum by Finite Element Method

Objective To investigate the contact mechanical characteristics of artifical acetabulum made of ultra-high molecule polyethylene (UHMWPE). Methods An acetabulum model was developed and meshed with free pattern. The contact pairs between acetabulum and femur head were built and the mechanical characteristics were analyzed under different conditions by finite element method (FEM). Results The magnitude of compress deformation decreased with the increase of friction coefficient and acetabulum diameter. Long-term stability of the hip joint was affected by contact layer thickness and contact area that have different characteristics under various thicknesses of the acetabulum. Conclusion The calculations show that acetabula with 7~9 mm thicknesses have better contact mechanical characteristics.