Real Time, In Vivo Mapping of Tibiofemoral Contact Pressures in Knee Arthroplasty

膝关节置换术中胫股接触压力的实时体内测绘

• 批准号: 7893935
• 负责人: Keat Ghee Ong
• 金额: $ 7.39万
• 依托单位: MICHIGAN TECHNOLOGICAL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-01 至 2012-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7893935
• 关键词: Address; Algorithms; Ambulatory Monitoring; Animal Model; Animals; Arthroplasty; Biocompatible; Ceramics; Detection; Development; Effectiveness; Electronics; Ensure; Failure; Figs - dietary; Funding; Future; Grant; Human; Implant; In Vitro; Information Systems; Knee; Knee joint; Knowledge; Long-Term Care; Magnetism; Maps; Measurement; Measures; Metals; Monitor; Movement; Patients; Phase; Polyethylenes; Process; Property; Research Project Grants; Speed; Stress; Surface; System; Techniques; Technology; Testing; Time; Work; biomaterial compatibility; computerized data processing; design; feeding; human subject; implantation; improved; in vitro testing; in vivo; knee replacement arthroplasty; pressure; prototype; public health relevance; response; sensor; tibia

DESCRIPTION (provided by applicant): A new sensor system is proposed for real time, in vivo monitoring of tibiofemoral contact pressures at knee arthroplasty implants for prediction of implant failure and understanding the real time dynamic of the implants when the user carries out his/her daily activities. The proposed sensor system will consist of a pressure-sensitive magnetic layer embedded under the top surface of the polyethylene insert of a knee arthroplasty implant for mapping the contact pressures between the polyethylene insert and femoral components. The pressure-sensing layer will consist of a grid of pressure/stress-sensitive magnetoelastic thin strips that change their magnetic properties with applied forces. Pressures will be measured at the pressure points, which are at the crossings of the grid. The magnetization of each sensing strip will be remotely measured by monitoring its magnetic higher-order harmonic fields. The responses of these sensing strips will be fed into an algorithm to determine the pressure loading at all pressure points, which allows real-time, in vivo determination of pressure profiles across the top surface of the polyethylene insert. Preliminary studies have demonstrated the remote detection of pressure across a surface with an array of magnetoelastic sensing strips. Prior to applying this technology to animal models or human trials, however, several issues will be addressed including the fabrication of reproducible and biocompatible sensing layer, development of a reliable detection system and data processing algorithm, and characterizing the response of the sensing layer ensuring its effectiveness. PUBLIC HEALTH RELEVANCE: There is a need to measure contact pressures at the femoral component of a knee arthroplasty implant to determine the wear and tear of the polyethylene insert of the implant. Today, most pressure monitoring systems for knee arthroplasty implants are either limited for in vitro or intraoperative uses, or cannot measure contact pressures across the surfaces of the femoral component and tibia plate. Development of a new technique for continuous, ambulatory monitoring of tibiofemoral contact pressures would be an enormous advance both in the detection of the implant failure and understanding the causes of the failure. While there are sensor systems that can either map the tibiofemoral contact pressures or provide continuous monitoring of the total pressure at the knee joint, to the PIs' knowledge there is no sensor system that can provide ambulatory mapping of tibiofemoral contact pressures. Therefore, the proposed sensor system, when successfully developed, will have a significant impact on the long term care of patients who receive knee arthroplasty implantation.

描述（由申请人提供）：提出了一种新的传感器系统，用于膝关节置换术植入物处胫股接触压力的真实的体内实时监测，以预测植入物失效并了解用户进行日常活动时植入物的真实的时间动态。申报的传感器系统将包括嵌入膝关节置换术植入物聚乙烯衬垫顶面下的压敏磁性层，用于标测聚乙烯衬垫和股骨部件之间的接触压力。压力传感层将由压力/应力敏感磁致弹性薄条的网格组成，这些薄条随着施加的力而改变其磁特性。压力将在网格交叉处的压力点处测量。将通过监测其高次谐波磁场来遥测每个感应条的磁化强度。这些传感条的响应将被输入到算法中，以确定所有压力点处的压力载荷，这允许实时、体内确定聚乙烯衬垫顶面上的压力分布。初步研究表明，用磁致弹性传感条阵列可以远程检测表面上的压力。然而，在将该技术应用于动物模型或人体试验之前，将解决几个问题，包括可再现和生物相容性传感层的制造，可靠检测系统和数据处理算法的开发，以及表征传感层的响应以确保其有效性。 公共卫生相关性：需要测量膝关节置换术植入物的股骨部件处的接触压力，以确定植入物的聚乙烯衬垫的磨损和撕裂。目前，用于膝关节置换术植入物的大多数压力监测系统要么局限于体外或术中使用，要么无法测量股骨部件和胫骨板表面的接触压力。开发一种用于胫股接触压力连续、动态监测的新技术，将是检测植入物失效和了解失效原因的巨大进步。虽然有传感器系统可以标测胫股接触压力或提供膝关节总压力的连续监测，但据PI所知，没有传感器系统可以提供胫股接触压力的动态标测。因此，所提出的传感器系统在成功开发后，将对接受膝关节置换术植入的患者的长期护理产生重大影响。