Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan.
Department of Orthopaedic Surgery, Kobe Kaisei Hospital, Kobe, Japan.
Knee Surg Sports Traumatol Arthrosc. 2018 Nov;26(11):3468-3473. doi: 10.1007/s00167-018-4935-1. Epub 2018 Apr 16.
This study aimed to determine the correlation between the change in joint line height calculated from the resected bone and insert thickness during surgery and the change in limb alignment following unicompartmental knee arthroplasty (UKA). It was hypothesized that joint line elevation is correlated with the change in limb alignment.
A total of 74 consecutive patients diagnosed with either isolated medial compartmental osteoarthritis (38 patients) or spontaneous osteonecrosis of the knee (36 patients) were included. The thickness of the proximal tibial and distal femoral bony cuts was measured during surgery; using these values, the medial joint line elevation of the tibia (MJLET) and medial joint line reduction of the femur (MJLRF) were defined. The correlation between the amount of change in the hip-knee-ankle (HKA) angle before and after surgery (δHKA) and the thickness of the tibial insert (TI), MJLET, or MJLRF were evaluated.
The mean values of δHKA, TI, MJLET, and MJLRF were 5.0° ± 2.6°, 8.5 ± 0.8, 4.4 ± 1.3, and 0.0 ± 1.1 mm, respectively. The δHKA had a significant, but weak-positive correlation with the TI (P = 0.02), and moderate-positive correlation with MJLET (P < 0.001). However, no correlation was observed between δHKA and MJLRF.
The MJLET measured during surgery had a significant moderate-positive correlation with the change in limb alignment following medial UKA. For clinical relevance, the surgeon can predict postoperative limb alignment after UKA by considering, intraoperatively, both the insert thickness and the depth of resection at the proximal tibia thus minimizing technical error to obtain an optimal alignment after UKA.
Diagnostic study, level II.
本研究旨在确定手术中从切除骨和插入物厚度计算得出的关节线高度变化与单髁膝关节置换术后下肢对线变化之间的相关性。假设关节线抬高与下肢对线的变化相关。
共纳入 74 例连续患者，诊断为孤立性内侧间室骨关节炎（38 例）或自发性膝关节坏死（36 例）。术中测量胫骨近端和股骨远端骨切的厚度；使用这些值，定义胫骨内侧关节线抬高（MJLET）和股骨内侧关节线减少（MJLRF）。评估手术前后髋关节-膝关节-踝关节（HKA）角度变化量（δHKA）与胫骨插入物（TI）、MJLET 或 MJLRF 厚度之间的相关性。
δHKA、TI、MJLET 和 MJLRF 的平均值分别为 5.0°±2.6°、8.5±0.8、4.4±1.3 和 0.0±1.1mm。δHKA 与 TI 呈显著的正相关（P=0.02），与 MJLET 呈中度正相关（P<0.001）。然而，δHKA 与 MJLRF 之间没有相关性。
术中测量的 MJLET 与内侧 UKA 后下肢对线的变化有显著的中度正相关。从临床相关性来看，外科医生可以通过考虑术中插入物厚度和胫骨近端切除深度来预测 UKA 后的下肢对线，从而将技术误差最小化，以获得 UKA 后的最佳对线。
诊断研究，II 级。
