Department of Orthopedics and Traumatology, Institute of Movement and Locomotion, St. Marguerite Hospital, Marseille, France.
Department of Orthopaedic Surgery, Reims Teaching Hospital, Hôpital Maison Blanche, Reims, France.
J Arthroplasty. 2024 Dec;39(12):2970-2976. doi: 10.1016/j.arth.2024.06.012. Epub 2024 Jun 14.
Mechanical alignment after total knee arthroplasty (TKA) is still widely used in the surgical community, but the alignment finally obtained by conventional techniques remains uncertain. The recent Coronal Plane Alignment of the Knee (CPAK) classification distinguishes 9 knee phenotypes according to constitutional alignment and joint line obliquity (JLO). The aim of this study was to assess the phenotypes of osteoarthritic patients before and after TKA using mechanical alignment and to analyze the influence of CPAK restoration on functional outcomes.
This retrospective multicenter study included 178 TKAs with a minimum follow-up of 2 years. Patients were operated on using a conventional technique with the goal of neutral mechanical alignment. The CPAK grade (1 to 9), considering the arithmetic Hip-Knee-Ankle angle (aHKA) and the JLO, was determined before and after TKA. Functional results were assessed using the following patient-reported outcome measures: Knee Injury and Osteoarthritis Outcome Score, the Simple Knee Value, and the Forgotten Joint Score.
A true neutral mechanical alignment was obtained in only 37.1%. Isolated restoration of JLO was found in 31.4%, and isolated restoration of the aHKA in 44.9%. Exact restoration of the CPAK phenotype was found in 14.6%. Restoration of the CPAK grade was associated with an improvement in the "daily living": 79.2 ± 5.3 versus 62.5 ± 2.3 (R = 0.05, P < .05) and "Quality of life" Knee Injury and Osteoarthritis Outcome Score subscales: 73.8 ± 5.0 versus 62.9 ± 2.2 (R = 0.02, P < .05).
This study shows that few neutral mechanical alignments are finally obtained after TKA by conventional technique. A major number of patients present a postoperative modification of their constitutional phenotype. Functional results at 2 years of follow-up appear to be improved by the restoration of the CPAK phenotype, JLO, and aHKA.
III, Retrospective Cohort Study.
全膝关节置换术后（TKA）的机械对线仍在外科领域广泛应用，但传统技术最终获得的对线结果并不确定。最近的膝关节冠状面对线（CPAK）分类根据固有对线和关节线倾斜（JLO）将 9 种膝关节表型区分开来。本研究旨在使用机械对线评估 TKA 前后骨关节炎患者的表型，并分析 CPAK 恢复对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线对线的影响因素分析及其对运动训练的启示。
本研究采用回顾性队列研究方法，纳入 178 例接受 TKA 治疗且随访时间至少 2 年的患者。患者均采用传统技术进行手术，以获得机械对线。通过测量手术前后的股胫角（HKA）和关节线倾斜角（JLO），评估患者的膝关节对线情况，并使用 CPAK 分类系统对患者进行分类。同时，使用膝关节功能评分量表（KSS）评估患者的膝关节功能。
仅有 37.1%的患者获得了真正的机械对线。31.4%的患者仅恢复了 JLO，44.9%的患者仅恢复了 HKA。只有 14.6%的患者恢复了准确的 CPAK 表型。CPAK 表型的恢复与患者的膝关节功能改善相关，尤其是在“日常生活活动”和“生活质量”方面。
本研究表明，通过传统技术进行 TKA 后，仅有少数患者获得了真正的机械对线。大多数患者术后膝关节表型发生了改变。CPAK 表型的恢复与患者的膝关节功能改善相关。
