Tominaga Yusuke, Kinoshita Tomofumi, Hino Kazunori, Kutsuna Tatsuhiko, Watamori Kunihiko, Tsuda Takashi, Horita Yusuke, Takao Masaki
Department of Orthopaedic Surgery Minamimatsuyama Hospital Matsuyama Ehime Japan.
Department of Orthopaedic Surgery Ehime University Graduate School of Medicine Toon Ehime Japan.
J Exp Orthop. 2024 Nov 14;11(4):e70093. doi: 10.1002/jeo2.70093. eCollection 2024 Oct.
This study investigated the tibiofemoral contact point (CP) on standing lateral radiographs in knee osteoarthritis and assessed the relationship between CP and pre- and postoperative knee kinematics in total knee arthroplasty (TKA).
The intraoperative knee status of 46 knees with varus deformity that underwent bicruciate stabilized TKA using a navigation system was investigated. The intraoperative anteroposterior (AP) position of the femur relative to the tibia at maximum extension, 15°, 30°, 45°, 60° and 90° was evaluated by the navigation system before and after TKA. The CP, defined as the CP between the femur and tibia, was assessed on standing lateral radiographs at the maximum extension of the knee before and 1 year after TKA. CP was expressed as the ratio of tibial plateau distance on a scale of 0-1, with 0 indicating the most anterior position of the femur relative to the tibia.
The mean CP on standing lateral radiographs was 0.54 ± 0.12 and 0.46 ± 0.08 before and after TKA, respectively. The postoperative CP was significantly more anterior than the preoperative CP ( = 0.0002). The mean AP position of the femur relative to the tibia moved anteriorly during early knee flexion both before and after TKA, representing nonanatomical AP movement. The preoperative posterior CP group (CP > 0.54) showed more nonanatomical AP movement from 15° to 60° before and after TKA compared with the preoperative anterior CP group (CP < 0.54).
Preoperative posterior deviation of the femur relative to the tibia in the standing position was a predictive factor for nonanatomical AP knee kinematics. Biomechanical analysis of postoperative knees will be necessary; however, surgeons should focus on preoperative tibiofemoral CP on standing lateral radiographs to predict knee kinematics.
Level Ⅲ.
本研究调查了膝关节骨关节炎站立位侧位X线片上的胫股接触点（CP），并评估了CP与全膝关节置换术（TKA）术前和术后膝关节运动学之间的关系。
研究了46例使用导航系统进行双交叉韧带稳定TKA的内翻畸形膝关节的术中膝关节状态。通过导航系统评估TKA前后，在最大伸展、15°、30°、45°、60°和90°时股骨相对于胫骨的术中前后（AP）位置。CP定义为股骨与胫骨之间的接触点，在TKA术前和术后1年膝关节最大伸展时的站立位侧位X线片上进行评估。CP表示为胫骨平台距离的比值，范围为0至1，0表示股骨相对于胫骨的最前位置。
TKA术前和术后站立位侧位X线片上的平均CP分别为0.54±0.12和0.46±0.08。术后CP明显比术前CP更靠前（P = 0.0002）。TKA前后，在膝关节早期屈曲时，股骨相对于胫骨的平均AP位置均向前移动，表现为非解剖学的AP运动。与术前前侧CP组（CP < 0.54）相比，术前后侧CP组（CP > 0.54）在TKA前后从15°至60°时表现出更多的非解剖学AP运动。
站立位时股骨相对于胫骨的术前后侧偏移是膝关节非解剖学AP运动学的预测因素。虽然术后膝关节的生物力学分析是必要的；然而，外科医生应关注站立位侧位X线片上的术前胫股CP，以预测膝关节运动学。
Ⅲ级。
