Loddo Glauco, An Jae-Sung, Claes Steven, Jacquet Christophe, Kley Kristian, Argenson Jean-Noël, Sharma Akash, Ollivier Matthieu
Department of Orthopaedics and Traumatology, University of Turin, Turin, Italy.
Orthopedic Surgery Department, Institut du Mouvement et de l'appareil locomoteur, Hôpital Sainte-Marguerite, Aix-Marseille Université, Marseille, France.
Knee Surg Sports Traumatol Arthrosc. 2024 Jun;32(6):1557-1570. doi: 10.1002/ksa.12168. Epub 2024 Apr 21.
While the coronal plane alignment of the knee (CPAK) classification serves as a useful guide in personalising total knee arthroplasty (TKA), the extent of its correlation with segmental coronal extra-articular knee deformities remains uncertain. This study aims to investigate the potential correlation between CPAK matrix groups and segmental coronal extra-articular deformities in prearthritic knees, shedding light on the relationship between these two factors that seems to be both essential to perform personalised TKA.
A radiological assessment of 1240 nonarthritic knees was performed by evaluating lower limb measurements following the protocol established by Paley et al. Subsequently, all knees were classified into their respective CPAK matrix groups. In our quest to discern any correlation between the CPAK matrix groups and the presence of segmental coronal extra-articular knee deformities, nine potential coronal extra-articular deformity phenotype (CEDP) groupswere identified based on medial proximal tibial angle (MPTA) and mechanical lateral distal femoral angle (mLDFA). Neutral values for MPTA and mLDFA were set at 90.0° ± 3.0° and then at 87.0° ± 2.0°. Each CPAK matrix group underwent detailed coronal morphology analysis and then, segmental coronal extra-articular deformities were assessed by comparing them with the CEDP groups.
The study revealed a mean hip-knee-ankle angle (HKA) of 178.6° ± 4.4°, mLDFA of 86.9° ± 2.5°, MPTA of 85.4° ± 2.4°, arithmetic HKA of -1.4° ± 3.2° and joint line obliquity of 172.5° ± 3.7°. The varus CPAK groups (I/IV/VII) included 435 patients, the neutral groups (II/V/VIII) comprised 630 patients and the valgus groups (III/VI/IX) had 175 patients. Notably, CPAK matrix groups were not distinctly associated with specific coronal extra-articular deformity phenotype (CEDP) groups. Particularly among the most common CPAK matrix groups (I/II/III/IV/V), there was a significant variation in segmental coronal extra-articular deformity patterns. Moreover, when neutral MPTA/mLDFA values were set at 87.0° ± 2.0°, the CPAK matrix groups exhibited even greater variability in coronal extra-articular deformities.
The CPAK matrix groups do not exhibit a direct correlation with a specific extra-articular deformity pattern (CEDP), thus rendering them unsuitable for determining segmental coronal extra-articular knee deformities.
Level III, retrospective diagnostic study.
虽然膝关节冠状面排列（CPAK）分类在全膝关节置换术（TKA）个体化方面是一个有用的指导，但它与节段性冠状面关节外膝关节畸形的相关程度仍不确定。本研究旨在探讨CPAK矩阵组与关节炎前期膝关节节段性冠状面关节外畸形之间的潜在相关性，以阐明这两个因素之间的关系，这两个因素似乎对进行个体化TKA都至关重要。
按照Paley等人制定的方案，通过评估下肢测量值对1240例非关节炎膝关节进行放射学评估。随后，将所有膝关节分类到各自的CPAK矩阵组中。为了确定CPAK矩阵组与节段性冠状面关节外膝关节畸形的存在之间的任何相关性，基于胫骨近端内侧角（MPTA）和股骨远端外侧机械角（mLDFA）确定了九个潜在的冠状面关节外畸形表型（CEDP）组。MPTA和mLDFA的中性值设定为90.0°±3.0°，然后设定为87.0°±2.0°。对每个CPAK矩阵组进行详细的冠状面形态分析，然后通过与CEDP组比较来评估节段性冠状面关节外畸形。
研究显示平均髋-膝-踝角（HKA）为178.6°±4.4°，mLDFA为86.9°±2.5°，MPTA为85.4°±2.4°，算术HKA为-1.4°±3.2°，关节线倾斜度为172.5°±3.7°。内翻CPAK组（I/IV/VII）包括435例患者，中性组（II/V/VIII）包括630例患者，外翻组（III/VI/IX）有175例患者。值得注意的是，CPAK矩阵组与特定的冠状面关节外畸形表型（CEDP）组没有明显关联。特别是在最常见的CPAK矩阵组（I/II/III/IV/V）中，节段性冠状面关节外畸形模式存在显著差异。此外，当中性MPTA/mLDFA值设定为87.0°±2.0°时，CPAK矩阵组在冠状面关节外畸形方面表现出更大的变异性。
CPAK矩阵组与特定的关节外畸形模式（CEDP）没有直接相关性，因此不适合用于确定节段性冠状面关节外膝关节畸形。
III级，回顾性诊断研究。
