Design and Evaluation of Instrumented Smart Knee Implant
Design and Evaluation of Instrumented Smart Knee Implant
复制标题
DOI：
10.1109/tbme.2010.2058806
复制
发表时间：
2011-04-01
影响因子：
4.6
通讯作者：
Roux, Christian
中科院分区：
文献类型：
--
作者：
Almouahed, Shaban;Gouriou, Manuel;Roux, Christian
全膝关节置换术（TKA）中韧带平衡的目标是在对线良好的假体膝关节的内侧和外侧间室之间对称分布胫股压缩力，以及在屈曲和伸展时重建矩形和相同的胫股间隙。目前，计算机辅助全膝关节置换术（CATKA）可确保膝关节机械轴的正确对线和屈曲和伸展间隙的完美均衡。然而，手术时侧副韧带的任何残余不平衡都可能导致术后负重活动期间的过度不平衡，从而使膝关节侧副韧带承受增加的负荷。这反过来又导致聚乙烯磨损加速，从而导致TKA早期失效。本研究中提出的内固定胫骨植入物可以通过基于压力中心（COP）的方法，在术后评估和监测假体膝关节的术后残余韧带失衡的进展，由于CATKA，假体膝关节在手术期间完全对线。这种方法依赖于测量术后期间COP位置相对于该期间开始时记录的参考位置的相对位移。该测量针对代表整个步态周期的六个预定屈曲角度执行。胫骨植入物除了在监测COP位置中发挥作用外，还可以产生电力，这要归功于胫骨托内嵌入的压电陶瓷，以实现这一双重任务。已经进行了实验和有限元分析（FEA）研究，以验证用于术后评估残余膝关节松弛的方法。有关电能产生和数据传输的问题将在另一篇论文中详细讨论。
The goal of ligament balancing in total knee arthroplasty (TKA) is to distribute the tibiofemoral compressive forces symmetrically between the medial and lateral compartments of a well-aligned prosthetic knee, as well as to reestablish a rectangular and identical tibiofemoral gap in both flexion and extension. Nowadays, the proper alignment of knee mechanical axis and the perfect equalization of flexion and extension gaps are ensured by computer-assisted TKA (CATKA). Nevertheless, any residual imbalance of collateral ligaments at the time of surgery can lead to an excessive imbalance in the postoperative period during the weight-bearing activities, which subject the knee collateral ligaments to increased loading. This in turn leads to an accelerated polyethylene wear, and consequently, to early failure of TKA. The instrumented tibial implant proposed in this study can postoperatively assess and monitor the progression of residual postoperative ligament imbalance of a prosthetic knee, which is perfectly aligned during the surgery thanks to CATKA, via a center-of-pressure (COP)-based approach. This approach depends on the measurement of relative displacement of COP position during the postoperative period with respect to a reference position recorded at the beginning of this period. This measurement is performed for six predetermined flexion angles representative of an entire gait cycle. The tibial implant can also generate the electrical power in addition to their role in monitoring the COP position thanks to the piezoceramics embedded within the tibial tray to achieve this twofold task. Experimental and finite-element analysis (FEA) studies have been conducted to validate the methodology used for the postoperative assessment of residual knee laxity. The issues concerning electrical energy generation and data transmission will be thoroughly discussed in another paper.