Zhao Yuhu, Liu Xin, Tao Huaqiang, Liang Xiaolong, Zheng Kai, Zhou Jun, Geng Dechun, Xu Yaozeng
Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, 215006, China.
Department of Orthopaedics, The First Affiliated Hospital of Xiamen University, Xiamen, 361000, China.
Arch Orthop Trauma Surg. 2024 Dec 27;145(1):97. doi: 10.1007/s00402-024-05730-7.
Lateral unicompartmental knee arthroplasty (UKA) is relatively less common than medial UKA. There has been no comparative analysis of the constitutional phenotypes of knees that underwent medial and lateral UKA. Therefore, this study aimed to compare the Coronal Plane Alignment of the Knee (CPAK) classification of knees that underwent medial and lateral UKA. Furthermore, the study analyzed whether CPAK phenotypes were maintained or altered after medial or lateral UKA.
We retrospectively analyzed consecutive patients who underwent UKA. A radiological analysis was conducted using an EOS imaging system, and demographic data of patients undergoing UKA were collected. Performed measurements included the mechanical hip-knee-ankle angle (mHKA), lateral distal femur angle (LDFA), and medial proximal tibia angle (MPTA), which were analyzed both before and after UKA. The CPAK classification was used to classify knee alignment phenotypes.
A total of 310 knees of 244 patients were included in the study that underwent non-robotically assisted, fixed-bearing UKA (279 medial; 31 lateral). Preoperatively, the most common categories for knees were Type I (varus mechanical axis, 53.8%) in medial UKA and Type III (valgus alignment, 77.4%) in lateral UKA. Postoperatively, Type II (neutral mechanical axis) became the most common type for both groups, accounting for 34.1% in the medial UKA group and 25.8% in the lateral UKA group. Only 31.3% preserved their preoperative CPAK classification after the surgery (32.3% and 22.6%, respectively).
The CPAK classification differs significantly between knees that underwent medial and lateral UKA. While 31.3% of knees maintained their native knee phenotype, there is a tendency towards a neutrally aligned classification after surgery for both medial and lateral UKA. The CPAK classification optimizes preoperative categorization and may assist surgeons in tailoring personalized therapies to improve clinical outcomes.
Level III.
外侧单髁膝关节置换术（UKA）相对内侧UKA较少见。目前尚无对接受内侧和外侧UKA的膝关节结构表型进行的比较分析。因此，本研究旨在比较接受内侧和外侧UKA的膝关节的冠状面排列（CPAK）分类。此外，该研究分析了内侧或外侧UKA后CPAK表型是否保持或改变。
我们回顾性分析了连续接受UKA的患者。使用EOS成像系统进行放射学分析，并收集接受UKA患者的人口统计学数据。进行的测量包括机械髋-膝-踝角（mHKA）、股骨远端外侧角（LDFA）和胫骨近端内侧角（MPTA），在UKA前后均进行分析。CPAK分类用于对膝关节排列表型进行分类。
本研究共纳入244例患者的310个膝关节，均接受非机器人辅助的固定平台UKA（279个内侧；31个外侧）。术前，内侧UKA中最常见的类别是I型（内翻机械轴，53.8%），外侧UKA中最常见的类别是III型（外翻排列，77.4%）。术后，II型（中立机械轴）成为两组中最常见的类型，内侧UKA组占34.1%，外侧UKA组占25.8%。术后只有31.3%的患者保持术前的CPAK分类（分别为32.3%和22.6%）。
接受内侧和外侧UKA的膝关节之间CPAK分类存在显著差异。虽然31.3%的膝关节保持其原始膝关节表型，但内侧和外侧UKA术后均有向中立排列分类转变的趋势。CPAK分类优化了术前分类，可能有助于外科医生制定个性化治疗方案以改善临床结果。
III级。
