Ceramic Tibia for Mobile Bearing Knee

描述(申请人提供)：移动式轴承TKA植入物是首选，因为它们有可能更好地恢复自然的膝关节运动学，如果与增加磨损相关的重要临床问题得到解决，可能会得到更多的接受。同样，长期克服聚乙烯(PE)胫骨植入物的材料疲劳失效将是延长更受欢迎的固定轴承TKA植入物的寿命、活动范围和功能的重要一步。在第一阶段，我们成功地证明了一种用于TKA植入物的新型超低磨损轴承的可行性，方法是开发一种针对现有CoCr合金进行低摩擦连接的新型陶瓷并进行磨损测试。标准测试表明，这种新型陶瓷材料具有最高的强度、韧性和威布尔模数组合，比Biolox Delta的当前状态有了显著的提高。我们还在销盘测试中证明，在接触应力提高3倍的情况下，与CoCrPE轴承相比，多向磨损减少了10倍。这一成功表明了一种新型替代TKA植入轴承的临床潜力，该轴承具有超低磨损和高安全特性：带陶瓷胫骨植入件的COCR股骨髁。如果成功，这种新型的TKA轴承具有消除PE材料失效的潜力，并有望将TKA植入物的寿命提高2-3倍。事实上，这种轴承有可能首次为TKA植入物引入一种独特、安全和有效的替代轴承。在第二阶段，我们的目标是通过开发和展示实际TKA植入组件的磨损性能、机械和生物安全性来扩展这些结果，这些组件在生理/临床上具有更相关的几何形状。在第二阶段，我们建议通过开发、优化和体外演示一系列全面的、统计上严格的实验设计来扩展这些有希望的结果，包括磨损性能、机械安全性和功能。我们还建议在膝关节模拟器上对移动和固定轴承设计的实际TKA轴承部件进行1000万次磨损测试，使用与生理相关的测试参数，以证实新提出的轴承的优越性。主要的整形外科植入物制造商已经表示对我们的技术感兴趣，并在评估新型TKA轴承方面进行合作。

DESCRIPTION (provided by applicant): Mobile bearing TKA implants are preferred owing to their potential to better restore natural knee kinematics, and could find increased acceptance if the important clinical concern related to increased wear is addressed. Equally, overcoming the materials fatigue related failures of polyethlylene (PE) tibial inserts over the long term would be a significant step forward in extending the life, range of motion and function of the more popular fixed bearing TKA implants. In Phase I, we successfully demonstrated the feasibility of a novel, ultra-low wear bearing for TKA implants by developing and wear testing of a new ceramic optimized for low friction articulation against established CoCr alloys. The novel ceramic material was shown in standard tests to possess the highest combination of strength, toughness and Weibull modulus, with a significant enhancement over current state of the art Biolox Delta. We have also demonstrated in pin on disc tests a 10 fold reduction in multidirectional wear compared to CoCr-PE bearings, under a 3X higher contact stress. This success points to the clinical potential of a novel alternate TKA implant bearing with ultra-low wear and high safety characteristics: a CoCr femoral condyle/ with a ceramic tibia insert. If successful, this novel TKA bearing offers the potential to eliminate PE material failure and promises to increase the life of TKA implants by a factor of 2 - 3X. Indeed, this bearing has the potential to introduce a unique, safe and effective alternative bearing for the first time, for TKA implants. In Phase II, we aim to extend these results by developing and demonstrating the wear performance, mechanical and biological safety of actual TKA implant components in a physiologically / clinically more relevant geometry. In Phase II, we propose to extend these promising results by developing, optimizing and demonstrating in vitro, the wear performance, mechanical safety and function in a set of comprehensive, statistically rigorous experimental designs. We also propose to conduct wear tests to 10 million cycles in a knee simulator on actual TKA bearing components of both mobile and fixed bearing designs, using physiologically relevant test parameters, to confirm the superiority of the novel proposed bearings. Major orthopedic implant manufacturers have expressed interest in our technology and collaborating on the evaluation of the novel TKA bearings.