Bertugli Enrico, Zambianchi Francesco, Batailler Cécile, Bazzan Gabriele, Lustig Sébastien, Catani Fabio
Department of Orthopaedic Surgery, Azienda Ospedaliero-Universitaria Policlinico di Modena, University of Modena and Reggio-Emilia, Modena, Modena, Italy.
Orthopaedic Surgery and Sports Medicine Department, Croix-Rousse Hospital, Lyon University Hospital, Lyon, France.
Knee Surg Sports Traumatol Arthrosc. 2025 May;33(5):1773-1783. doi: 10.1002/ksa.12561. Epub 2024 Dec 12.
The purpose of this study was to assess the impact of post-operative coronal plane alignment of the knee (CPAK) class change on functional outcomes and determine the rate and type of CPAK class change after image-based robotic arm-assisted (RA)-total knee arthroplasty (TKA) performed with functional alignment (FA) at two different centres.
The present retrospective, observational, multicentre study included 201 patients treated with RA-TKA between October 2020 and April 2022 at two different centres. The radiographic CPAK classification was adapted using CT images to achieve pre- and post-operative knee categorization into CPAK classes. At a minimum of 1 year post-operatively, patients were administered the Forgotten Joint Score-12 (FJS-12) and surveyed about their post-operative satisfaction level using a 5-level Likert scale (5-LLS).
The most common preoperative overall CPAK classes were: Types II, I, III, IV and V. Implant positioning after RA-TKA with FA within the alignment boundaries, determined distribution in the CPAK classification, predominantly maintaining classes I, II, IV, and V. No statistically significant FJS-12 differences were detected between subjects who maintained and changed their preoperative CPAK class. The mean 5-LLS for satisfaction in patients where the preoperative CPAK class was maintained intraoperatively was 4.4 ± 1.1 (range = 1-5), while subjects having the CPAK class changed had a mean 5-LLS of 4.4 ± SD 1.0 (range 1-5).
In the setting of image-based RA-TKA with FA, CPAK can be changed within a 'functional safe-zone', without compromising functional outcomes. Good functional outcomes are the result of a stable and balanced knee with soft-tissue preservation, regardless of the maintenance of the preoperative CPAK class.
Level III.
本研究旨在评估膝关节术后冠状面排列（CPAK）类别变化对功能结局的影响，并确定在两个不同中心进行基于影像的机器人手臂辅助（RA）全膝关节置换术（TKA）并采用功能对线（FA）后CPAK类别变化的发生率和类型。
本回顾性、观察性、多中心研究纳入了2020年10月至2022年4月期间在两个不同中心接受RA-TKA治疗的201例患者。使用CT图像采用放射学CPAK分类法，对术前和术后膝关节进行CPAK类别分类。术后至少1年，对患者进行遗忘关节评分-12（FJS-12）评估，并使用5级李克特量表（5-LLS）调查其术后满意度水平。
术前最常见的总体CPAK类别为：II型、I型、III型、IV型和V型。在对线边界内采用FA的RA-TKA术后植入物位置决定了CPAK分类中的分布，主要维持I、II、IV和V类。在术前CPAK类别维持不变和发生变化的受试者之间，未检测到FJS-12有统计学意义的差异。术中维持术前CPAK类别的患者满意度平均5-LLS为4.4±1.1（范围=1-5），而CPAK类别发生变化的受试者平均5-LLS为4.4±标准差1.0（范围1-5）。
在采用FA的基于影像的RA-TKA中，CPAK可在“功能安全区”内改变，而不影响功能结局。良好的功能结局是膝关节稳定、平衡且保留软组织的结果，无论术前CPAK类别是否维持不变。
III级。
