Hua Xijin, Wang Ling, Al-Hajjar Mazen, Jin Zhongmin, Wilcox Ruth K, Fisher John
Institute of Medical and Biological Engineering, School of Mechanical Engineering, University of Leeds, Leeds, UK
State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an, Shanxi, China.
Proc Inst Mech Eng H. 2014 Jul;228(7):682-92. doi: 10.1177/0954411914541830. Epub 2014 Jun 24.
Finite element models are becoming increasingly useful tools to conduct parametric analysis, design optimisation and pre-clinical testing for hip joint replacements. However, the verification of the finite element model is critically important. The purposes of this study were to develop a three-dimensional anatomic finite element model for a modular metal-on-polyethylene total hip replacement for predicting its contact mechanics and to conduct experimental validation for a simple finite element model which was simplified from the anatomic finite element model. An anatomic modular metal-on-polyethylene total hip replacement model (anatomic model) was first developed and then simplified with reasonable accuracy to a simple modular total hip replacement model (simplified model) for validation. The contact areas on the articulating surface of three polyethylene liners of modular metal-on-polyethylene total hip replacement bearings with different clearances were measured experimentally in the Leeds ProSim hip joint simulator under a series of loading conditions and different cup inclination angles. The contact areas predicted from the simplified model were then compared with that measured experimentally under the same conditions. The results showed that the simplification made for the anatomic model did not change the predictions of contact mechanics of the modular metal-on-polyethylene total hip replacement substantially (less than 12% for contact stresses and contact areas). Good agreements of contact areas between the finite element predictions from the simplified model and experimental measurements were obtained, with maximum difference of 14% across all conditions considered. This indicated that the simplification and assumptions made in the anatomic model were reasonable and the finite element predictions from the simplified model were valid.
有限元模型正日益成为进行髋关节置换参数分析、设计优化和临床前测试的有用工具。然而，有限元模型的验证至关重要。本研究的目的是开发一种用于模块化金属对聚乙烯全髋关节置换的三维解剖有限元模型，以预测其接触力学，并对从解剖有限元模型简化而来的简单有限元模型进行实验验证。首先开发了一种解剖模块化金属对聚乙烯全髋关节置换模型（解剖模型），然后以合理的精度将其简化为一个简单的模块化全髋关节置换模型（简化模型）进行验证。在利兹ProSim髋关节模拟器中，在一系列加载条件和不同髋臼倾斜角度下，对具有不同间隙的模块化金属对聚乙烯全髋关节置换轴承的三种聚乙烯衬垫关节表面的接触面积进行了实验测量。然后将简化模型预测的接触面积与在相同条件下实验测量的接触面积进行比较。结果表明，对解剖模型进行的简化并没有显著改变模块化金属对聚乙烯全髋关节置换接触力学的预测结果（接触应力和接触面积的变化小于12%）。简化模型的有限元预测结果与实验测量的接触面积之间取得了良好的一致性，在所有考虑的条件下最大差异为14%。这表明解剖模型中所做的简化和假设是合理的，简化模型的有限元预测结果是有效的。
