Forchelet David, Simoncini Matteo, Arami Arash, Bertsch Arnaud, Meurville Eric, Aminian Kamiar, Ryser Peter, Renaud Philippe
Microsystems Laboratory (LMIS4), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
Laboratory of Microengineering for Manufacturing (LPM), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
Sensors (Basel). 2014 Aug 14;14(8):15009-21. doi: 10.3390/s140815009.
Total knee arthroplasty is a widely performed surgical technique. Soft tissue force balancing during the operation relies strongly on the experience of the surgeon in equilibrating tension in the collateral ligaments. Little information on the forces in the implanted prosthesis is available during surgery and post-operative treatment. This paper presents the design, fabrication and testing of an instrumented insert performing force measurements in a knee prosthesis. The insert contains a closed structure composed of printed circuit boards and incorporates a microfabricated polyimide thin-film piezoresistive strain sensor for each condylar compartment. The sensor is tested in a mechanical knee simulator that mimics in-vivo conditions. For characterization purposes, static and dynamic load patterns are applied to the instrumented insert. Results show that the sensors are able to measure forces up to 1.5 times body weight with a sensitivity fitting the requirements for the proposed use. Dynamic testing of the insert shows a good tracking of slow and fast changing forces in the knee prosthesis by the sensors.
全膝关节置换术是一种广泛应用的外科技术。手术过程中的软组织力平衡在很大程度上依赖于外科医生平衡侧副韧带张力的经验。在手术和术后治疗期间，关于植入假体中的力的信息很少。本文介绍了一种用于在膝关节假体中进行力测量的仪器化插入物的设计、制造和测试。该插入物包含一个由印刷电路板组成的封闭结构，并为每个髁间室集成了一个微加工的聚酰亚胺薄膜压阻应变传感器。该传感器在模拟体内条件的机械膝关节模拟器中进行测试。为了进行特性描述，将静态和动态载荷模式应用于仪器化插入物。结果表明，这些传感器能够测量高达体重1.5倍的力，其灵敏度符合拟用要求。对该插入物的动态测试表明，传感器能够很好地跟踪膝关节假体中缓慢和快速变化的力。
