Waanders Daan, Janssen Dennis, Bertoldi Katia, Mann Kenneth A, Verdonschot Nico
Orthopaedic Research Laboratory, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
Comput Methods Biomech Biomed Engin. 2011 Feb;14(2):145-55. doi: 10.1080/10255842.2010.535814.
While including the cement-bone interface of complete cemented hip reconstructions is crucial to correctly capture their response, its modelling is often overly simplified. In this study, the mechanical mixed-mode response of the cement-bone interface is investigated, taking into account the effects of the well-defined microstructure that characterises the interface. Computed tomography-based plain strain finite element analyses models of the cement-bone interface are built and loaded in multiple directions. Periodic boundaries are considered and the failure of the cement and bone fractions by cracking of the bulk components are included. The results compare favourably with experimental observations. Surprisingly, the analyses reveal that under shear loading no failure occurs and considerable normal compression is generated to prevent interface dilation. Reaction forces, crack patterns and stress fields provide more insight into the mixed-mode failure process. Moreover, the cement-bone interface analyses provide details which can serve as a basis for the development of a cohesive law.
虽然纳入全骨水泥型髋关节重建的骨水泥-骨界面对于正确获取其反应至关重要，但其建模往往过于简化。在本研究中，考虑到表征该界面的明确微观结构的影响，对骨水泥-骨界面的机械混合模式反应进行了研究。构建了基于计算机断层扫描的骨水泥-骨界面平面应变有限元分析模型，并在多个方向上加载。考虑了周期性边界，并包括了由于大块部件开裂导致的骨水泥和骨部分的破坏。结果与实验观察结果相比具有优势。令人惊讶的是，分析表明在剪切载荷下不会发生破坏，并且会产生相当大的法向压缩以防止界面扩张。反作用力、裂纹模式和应力场为混合模式破坏过程提供了更多见解。此外，骨水泥-骨界面分析提供的细节可为内聚定律的发展提供基础。
