Improving the long-term performance of modular connections in artificial joints

自上个世纪中期以来，越来越多地使用人工关节来治疗患有关节疾病的患者。早期，主要治疗髋关节和膝关节，很少在60岁以下的人群中植入器械，因为植入物的存活率通常低于15年。人工关节在过去的50年里已经有了很大的改进，因此，尽管越来越多的年轻和更活跃的患者被植入人工关节，但预计15年后的存活率为90%或更高。在过去几年中引入的改进包括更多的组配式设计，这使得外科医生能够在术中最佳地调整关节、几何特征和对个体患者的固定。尽管使用计算机建模和精细的近生理测试进行了巨大的努力，但这些新设计中的一些似乎在其模块化连接处出现了问题。更常见的情况是，髋关节组配式股骨头-颈部界面处的腐蚀增加，尤其是在股骨头较大的髋关节中，这可能导致不良组织反应，如囊肿形成、假瘤和肌肉损伤。这项行业独立研究的长期目标是改善人工关节中组配式连接的性能，以减少因骨折、腐蚀和不良组织反应而导致的翻修。拟议的工作将着眼于模块化连接，通过故障分析的连接，计算机建模和体外测试的模块化连接的改进，从这个研究计划。一个关键的结果将是开发一种新型疲劳测试，包括大股骨头和髋关节植入物颈部之间的组配式连接的腐蚀。预期的翻修减少将提高人工关节的成功长期性能，使患者受益，并降低医疗保健成本。在马尼托巴大学和Concordia髋关节和膝关节研究所对HQP进行这一专业领域的培训，将支持加拿大医疗器械行业的发展。

Artificial joints have been used in increasing numbers since the middle of the last century to treat patients with diseased joints. Early on, mainly hip and knee joints were treated, and the devices were rarely implanted in persons younger than 60 years, as the implant survival rate was typically less than 15 years. Artificial joints have improved much in the last 50 years, so that a survival rate of 90% or more can be expected after 15 years, in spite of the fact that they are increasingly being implanted in younger and more active patients. Improvements that were introduced in the last few years included more modular designs, which allow surgeons intra-operatively to optimally adjust the articulation, geometric features and fixation to an individual patient. Despite enormous efforts using computer modeling and elaborate near physiological testing, it appears that some of these new designs develop problems at their modular connections. More frequently, there is an increase in corrosion at the modular head-neck interface of hip joints, especially in hips with larger heads that can lead to adverse tissue reactions such as the formation of cysts, pseudotumors and muscle damage. The long term goal of this industry independent research is to improve the performance of modular connections in artificial joints to achieve a reduction of revisions due to fractures, corrosion and adverse tissue reactions. The proposed work will look at modular connections through the failure analysis of explanted joints, computer modeling and in vitro testing of improvements of modular connections resulting from this research program. A key outcome will be the development of a novel fatigue test that includes corrosion of modular connections between large heads and the neck of hip implants. The expected reduction of revisions will increase the successful long-term performance of artificial joints benefiting the patients, and reduce the costs to health care. Training of HQP in this area of expertise at the University of Manitoba and the Concordia Hip and Knee Institute will support the growth of the medical device industry in Canada.