INTERFACE FAILURE IN TOTAL JOINT REPLACEMENTS

全关节置换术中的接口故障

• 批准号: 6769322
• 负责人: KENNETH A. MANN
• 金额: $ 21.66万
• 依托单位: UPSTATE MEDICAL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-07-15 至 2006-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6769322
• 关键词: arthroplasty; biomaterial development /preparation; biomaterial evaluation; biomaterial interface interaction; biomechanics; hip prosthesis; mechanical stress; medical implant science; medical rehabilitation related tag

Aseptic loosening continues to be a problem with total hip replacements. In cemented total hip replacement, mechanically induced loosening most often initiates at the stem-cement or cement-bone interface. Improving the outcomes of cemented total hip replacement is limited by our lack of understanding of the actual mechanical conditions that cause loosening, and the multifactorial nature of the failure process that depends on stem design, stem surface conditions, and cementing technique. In this work, a research program is described to investigate: (1) the specific mechanical fatigue conditions under which the stem-cement and cement-bone interfaces fail; (2) the manner in which stem design, stem surface, and cementing process contribute to the fatigue failure process at the interfaces and in the bulk cement; and (3) the interactions between these three design factors in affecting the fatigue failure process. The end goal of this research is to define design guidelines that will reduce the revision rates of cemented hip replacements due to implant loosening. It is the hypothesis of this work that stem design, stem surface, and cementing conditions can each effect the overall failure (loosening) of the implant system. In the proposed research, fracture mechanics-based approaches will be used to characterized the fatigue behavior and failure of the stem-cement and cement-bone interfaces. Models for interface response will be developed from a combination of experimental and theoretical methods, and these models will be verified by comparison of predicted to observed results for experiments that are different than those used for model development. Cyclic fatigue experiments of cemented stem construct will be performed with an aggressive stair climbing loading regime for each of the design conditions. These experiments will directly test the hypothesis stated above through use of a 23 factorial experimental design. Finally, fully 3-D fatigue models of each of the eight design cases will be performed to elucidate the failure mechanisms found in the experiments. When combined, the experimental and computational approaches will provide design guidelines that could significantly reduce revision rates of cemented hip replacements due to implant loosening.

无菌性松动仍然是全髋关节置换术的一个问题。 在骨水泥型全髋关节置换术中，机械性松动最常发生在股骨柄-骨水泥或骨水泥-骨界面。 由于我们缺乏对导致松动的实际力学条件的了解，以及取决于股骨柄设计、股骨柄表面条件和骨水泥固定技术的失效过程的多因素性质，因此，改善骨水泥型全髋关节置换术的结局受到限制。在这项工作中，描述了一项研究计划，以调查：（1）股骨柄-骨水泥和骨水泥-骨界面失效的特定机械疲劳条件;（2）股骨柄设计、股骨柄表面和骨水泥过程对界面和散装骨水泥中疲劳失效过程的影响方式;以及（3）这三个设计因素之间的交互作用对疲劳破坏过程的影响。 本研究的最终目标是确定设计指南，以降低因植入物松动导致的骨水泥型髋关节置换术的翻修率。这项工作的假设是，股骨柄设计、股骨柄表面和骨水泥条件均会影响植入物系统的整体失效（松动）。在拟议的研究中，将使用基于断裂力学的方法来表征股骨柄-骨水泥和骨水泥-骨界面的疲劳行为和失效。 界面响应的模型将开发从实验和理论方法相结合，这些模型将通过比较预测的观察结果的实验是不同于那些用于模型开发。 对于每种设计条件，将采用积极的爬楼梯载荷方案对骨水泥型股骨柄结构进行循环疲劳实验。 这些实验将通过使用23析因实验设计直接检验上述假设。 最后，全三维疲劳模型的八个设计案例中的每一个将被执行，以阐明在实验中发现的故障机制。当结合使用时，实验和计算方法将提供设计指南，可以显著降低由于植入物松动导致的骨水泥型髋关节置换术的翻修率。