University of Florence, Orthopaedic Clinic CTO, Florence, Italy.
J Arthroplasty. 2019 Apr;34(4):676-681. doi: 10.1016/j.arth.2018.12.042. Epub 2019 Jan 5.
Total knee arthroplasty (TKA) in patients with post-traumatic extra-articular deformity (EAD) is difficult to manage using conventional instrumentation techniques. In this study, we evaluate whether accelerometer navigation system can be a valuable option to make accurate bone resections and restore the neutral mechanical axis in complex TKA patients with EAD.
From May 2015 to June 2017, 18 consecutive TKA were performed in 18 patients with knee osteoarthritis with associated EAD. An accelerometer-based navigation system was used to guide tibial and femoral resection in the coronal and sagittal plane. Postoperative lower limb alignment in coronal plane and component position in coronal and sagittal plane was measured through full-leg weight-bearing X-ray. Clinical score were recorded using the Knee Society Score at the final follow-up.
The mean hip-knee-ankle angle was 0.9° ± 1.4° varus alignment. The coronal alignment of the femoral component was 89.2° ± 1.9°, and the coronal alignment of the tibial component was 89.4° ± 2.1°. The sagittal alignment of the femoral component was 93.2°± 1.9°, and the sagittal alignment of the tibial component was 84.4° ± 3.1°. At the final follow-up, the Knee Society Score was 89 points (range, 82-100), and the functional score was 86.7 points (range, 60-100). No intraoperative and postoperative surgical complications were reported using this technology.
Accelerometer-based navigation is accurate in achieving neutral mechanical alignment and optimal implant position after TKA in patients with EAD. This system should be considered a valuable option to the more complex technique of computer navigation or robotic surgery.
对于患有创伤后关节外畸形（EAD）的患者，全膝关节置换术（TKA）的处理较为困难，使用传统的器械技术难以进行。本研究评估了在患有 EAD 的复杂 TKA 患者中，加速度计导航系统是否可以成为一种准确进行骨骼切除并恢复中立机械轴的有价值的选择。
2015 年 5 月至 2017 年 6 月，对 18 例膝关节骨关节炎合并 EAD 的患者进行了 18 例 TKA。使用基于加速度计的导航系统在冠状面和矢状面引导胫骨和股骨的切除。通过下肢全长负重 X 线测量术后冠状面下肢对线和冠状面及矢状面的组件位置。最终随访时采用膝关节学会评分记录临床评分。
平均髋膝踝角为 0.9°±1.4°的内翻对线。股骨组件的冠状面排列为 89.2°±1.9°，胫骨组件的冠状面排列为 89.4°±2.1°。股骨组件的矢状面排列为 93.2°±1.9°，胫骨组件的矢状面排列为 84.4°±3.1°。最终随访时，膝关节学会评分为 89 分（范围，82-100），功能评分为 86.7 分（范围，60-100）。使用该技术未报告术中及术后手术并发症。
基于加速度计的导航系统在 EAD 患者的 TKA 后能够准确实现中立机械对线和最佳植入物位置。该系统应被视为计算机导航或机器人手术等更复杂技术的有价值的选择。
