Development and wear testing of bi-material bearing surfaces for hip arthroplasty

描述（由申请人提供）：髋关节置换术对于患有退行性关节疾病的患者是一种非常有效和成功的治疗方法。然而，在美国，翻修手术约占髋关节植入手术的13%，每年花费30亿美元，并且显著增加了患者的发病率和并发症风险。全髋关节置换术（THA）承载面磨损和/或失效是器械失效的主要原因之一，直接原因是承载关节不良或磨损碎片的有害影响。拟议的工作将开发和测试一种用于THA设备的新轴承。这种新颖的方法将减少轴承表面的损伤和磨损，与轴承设计的最先进的方法相比。如果这个项目是成功的，THA承载面的基本设计每年可能会改变成千上万的患者。预计该产品设计将减轻美国关节置换术的翻修负担。对失败的骨科设备的实验室研究使开发团队了解到当前工业设计的缺点。临床检索的独立研究提供了令人信服的证据，硬对硬的髋关节轴承失败是由意想不到的动态头缘接触驱动的。临床上经常发生磨损、疲劳失效和表面损伤。因此，拟议项目的目标是为人工髋关节开发新的承载表面，为患者提供硬对硬承载偶的高耐磨性，并在最需要的地方提供聚合物（如超高分子量聚乙烯）的韧性和抗冲击性。拟议的工作将通过对新轴承的进一步开发、制造、测试和建模来确定可行性。该研究计划将建立可测量和可重复的方案，用于测试拟议表面的弹性和耐磨性，将在高接触应力载荷下进行验证，以反映真实的体内条件，将建立新磨损界面概念的证明，并将开发承载界面力学行为的数值模型。要回答的问题包括模拟环境的有效性，所提出的材料界面的弹性，以及在所提出的轴承设计中预测损伤的能力。

DESCRIPTION (provided by applicant): Hip replacement surgery is a tremendously effective and successful treatment for patients suffering from degenerative joint disease. However, revision surgery accounts for about 13% of hip implant surgeries in the U.S., costing $3 billion annually and presenting significantly increased morbidity and risk of complication for patients. Wear and/or failure of total hip arthroplasty (THA) bearing surfaces is one of the leading causes of device failure, either directly because of poor bearing articulation or through the detrimental effects of wear debris. The proposed work will develop and test a new bearing to be employed in a THA device. This novel approach will reduce bearing surface damage and wear when compared to state of the art approaches in bearing design. If this project is successful, the fundamental design of the bearing surface in THA could change for hundreds of thousands of patients every year. It is expected that this product design will reduce the United States arthroplasty revision burden. Laboratory research in failed orthopedic devices has informed the development team's understanding of the shortcomings of current industry designs. Independent studies of clinical retrievals provide compelling evidence that hard-on-hard hip bearing failure is driven by unanticipated dynamic head-to-rim contact. Wear, fatigue failure, and surface damage occur clinically. Thus, the goal of the proposed project is to develop new bearing surfaces for artificial hips that offer patients the very high wear resistance of hard-on-hard bearing couples and also offer the toughness and impact resistance of polymers such as ultra-high molecular weight polyethylene where most needed. The proposed work will establish feasibility through further development, manufacture, testing and modeling of the new bearing. The research plan will establish measureable and repeatable protocols for testing resilience and wear resistance of proposed surfaces, will proceed to validation in high contact stress loading that reflects true in vivo conditions, will establish proof of concept of new wear interfaces, and will develop a numerical model of the mechanical behavior of the bearing interface. Questions to be answered include validity of the simulation environment, resilience of the proposed material interface, and the ability to predict damage in the proposed bearing designs.