Complex Joint Reconstruction Center, Hospital for Special Surgery, New York City, NY.
J Arthroplasty. 2018 Jul;33(7):1989-1993. doi: 10.1016/j.arth.2018.01.027. Epub 2018 Jan 31.
Computer-assisted surgical (CAS) navigation has been developed with the aim of improving the accuracy and precision of total knee arthroplasty (TKA) component positioning and therefore overall limb alignment. The historical goal of knee arthroplasty has been to restore the mechanical alignment of the lower limb by aligning the femoral and tibial components perpendicular to the mechanical axis of the femur and tibia. Despite over 4 decades of TKA component development and nearly 2 decades of interest in CAS, the fundamental question remains; does the alignment goal and/or the method of achieving that goal affect the outcome of the TKA in terms of patient-reported outcome measures and/or overall survivorship? The quest for reliable and reproducible achievement of the intraoperative alignment goal has been the primary motivator for the introduction, development, and refinement of CAS navigation. Numerous proprietary systems now exist, and rapid technological advancements in computer processing power are stimulating further development of robotic surgical systems. Three categories of CAS can be defined: image-based large-console navigation; imageless large-console navigation, and more recently, accelerometer-based handheld navigation systems have been developed.
A review of the current literature demonstrates that there are enough well-designed studies to conclude that both large-console CAS and handheld navigation systems improve the accuracy and precision of component alignment in TKA. However, missing from the evidence base, other than the subgroup analysis provided by the Australian Orthopaedic Association National Joint Replacement Registry, are any conclusive demonstrations of a clinical superiority in terms of improved patient-reported outcome measures and/or decreased cumulative revision rates in the long term. Few authors would argue that accuracy of alignment is a goal to ignore; therefore, in the absence of clinical evidence, many of the arguments against the use of large-console CAS navigation center on the prohibitive cost of the systems. The utilization of low-cost, handheld CAS navigation systems may therefore bridge this important gap, and over time, further clinical evidence may emerge.
计算机辅助手术（CAS）导航的发展旨在提高全膝关节置换术（TKA）组件定位的准确性和精度，从而实现整体肢体对线。膝关节置换术的历史目标是通过使股骨和胫骨组件垂直于股骨和胫骨的机械轴来恢复下肢的机械对线。尽管 TKA 组件的发展已经超过 40 年，CAS 的兴趣也已经近 20 年，但基本问题仍然存在；对线目标和/或实现该目标的方法是否会影响 TKA 的结果，从患者报告的结果测量和/或整体生存率方面来看？实现术中对线目标的可靠和可重复的追求一直是引入、开发和完善 CAS 导航的主要动力。现在存在许多专有系统，计算机处理能力的快速技术进步正在刺激机器人手术系统的进一步发展。可以定义三类 CAS：基于图像的大型控制台导航；无图像的大型控制台导航，以及最近开发的基于加速度计的手持式导航系统。
对当前文献的回顾表明，有足够数量的精心设计的研究可以得出结论，即大型控制台 CAS 和手持式导航系统都可以提高 TKA 中组件对线的准确性和精度。然而，除了澳大利亚矫形协会国家关节置换登记处提供的亚组分析之外，证据基础中缺少任何关于在改善患者报告的结果测量和/或长期降低累积翻修率方面具有临床优势的明确证据。很少有作者会认为对线的准确性是一个可以忽略的目标；因此，在缺乏临床证据的情况下，许多反对使用大型控制台 CAS 导航的论点都集中在系统成本过高。因此，低成本的手持式 CAS 导航系统的利用可能会填补这一重要空白，随着时间的推移，可能会出现更多的临床证据。
