For the past three decades, total knee replacement has become the main solution for progressed knee injuries and diseases. Due to a lack of postoperative in vivo data, a universal correlation between intra- and postoperative soft tissue balance in the knee joint has not been established. In this work, an instrumented knee implant design with six piezoelectric transducers embedded in the tibial bearing is proposed. The aim of the presented device is to measure the total and compartmental forces as well as to track the location of contact points on the medial and lateral compartments of the bearing. A numerical analysis using finite element software is first performed to obtain the best sensory system arrangement inside the bearing. The chosen design is then used to fabricate a prototype of the device. Several experiments are designed and performed using the prototype, and the ability of the proposed system to track the location and magnitude of applied compartmental forces on the bearing is evaluated. The experimental results show that the instrumented knee bearing is able to accurately measure the compartmental force quantities with a maximum error of 2.6% of the peak axial load, and the contact point locations with a maximum error of less than 1 mm.

在过去的三十年中，全膝关节置换术已成为进展性膝关节损伤和疾病的主要解决方案。由于缺乏术后体内数据，膝关节内和术后软组织平衡之间的普遍相关性尚未建立。在这项工作中，提出了一种在胫骨轴承中嵌入六个压电换能器的仪器化膝关节植入物设计。本装置的目的是测量总力和隔室力，并跟踪轴承内侧和外侧隔室上接触点的位置。首先使用有限元软件进行数值分析，以获得轴承内部的最佳传感系统布置。然后使用选定的设计来制造设备的原型。使用原型设计和执行了几个实验，并评估了所提出的系统跟踪轴承上施加的隔室力的位置和大小的能力。实验结果表明，仪表化膝关节轴承能够准确测量隔室力量，最大误差为峰值轴向载荷的 2.6%，接触点位置的最大误差小于 1 mm。