Mukherjee Kaushik, Gupta Sanjay
Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721 302, West Bengal, India.
Professor Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721 302, West Bengal, India e-mail:
J Biomech Eng. 2017 Sep 1;139(9). doi: 10.1115/1.4037223.
Bone ingrowth and remodeling are two different evolutionary processes which might occur simultaneously. Both these processes are influenced by local mechanical stimulus. However, a combined study on bone ingrowth and remodeling has rarely been performed. This study is aimed at understanding the relationship between bone ingrowth and adaptation and their combined influence on fixation of the acetabular component. Based on three-dimensional (3D) macroscale finite element (FE) model of implanted pelvis and microscale FE model of implant-bone interface, a multiscale framework has been developed. The numerical prediction of peri-acetabular bone adaptation was based on a strain-energy density-based formulation. Bone ingrowth in the microscale models was simulated using the mechanoregulatory algorithm. An increase in bone strains near the acetabular rim was observed in the implanted pelvis model, whereas the central part of the acetabulum was observed to be stress shielded. Consequently, progressive bone apposition near the acetabular rim and resorption near the central region were observed. Bone remodeling caused a gradual increase in the implant-bone relative displacements. Evolutionary bone ingrowth was observed around the entire acetabular component. Poor bone ingrowth of 3-5% was predicted around the centro-inferio and inferio-posterio-superio-peripheral regions owing to higher implant-bone relative displacements, whereas the anterio-inferior and centro-superior regions exhibited improved bone ingrowth of 35-55% due to moderate implant-bone relative displacement. For an uncemented acetabular CoCrMo component, bone ingrowth had hardly any effect on bone remodeling; however, bone remodeling had considerable influence on bone ingrowth.
骨长入和骨重塑是两个不同但可能同时发生的演化过程。这两个过程均受局部机械刺激的影响。然而，很少有关于骨长入和骨重塑的联合研究。本研究旨在了解骨长入与适应性之间的关系及其对髋臼部件固定的综合影响。基于植入骨盆的三维（3D）宏观有限元（FE）模型和植入物-骨界面的微观有限元模型，开发了一个多尺度框架。髋臼周围骨适应性的数值预测基于基于应变能密度的公式。在微观模型中使用机械调节算法模拟骨长入。在植入骨盆模型中观察到髋臼边缘附近的骨应变增加，而髋臼中心部分则出现应力屏蔽。因此，观察到髋臼边缘附近有渐进性的骨附着，而中心区域附近有骨吸收。骨重塑导致植入物与骨之间的相对位移逐渐增加。在整个髋臼部件周围观察到渐进性骨长入。由于植入物与骨之间的相对位移较大，预计在髋臼中心下和下后上周边区域的骨长入较差，为3%-5%，而由于植入物与骨之间的相对位移适中，前下和中心上区域的骨长入改善，为35%-55%。对于非骨水泥型髋臼钴铬钼部件，骨长入对骨重塑几乎没有影响；然而，骨重塑对骨长入有相当大的影响。
