Yang Jae-Hyuk, Dahuja Anshul, Kim Jin-Kak, Yun Se-Hyeok, Yoon Jung-Ro
Department of Orthopedic Surgery, Veterans Health Service Medical Center, 6-2 Dunchon Dong, Kangdong Ku, Seoul, Republic of Korea.
Knee Surg Sports Traumatol Arthrosc. 2016 Aug;24(8):2422-9. doi: 10.1007/s00167-015-3589-5. Epub 2015 Apr 9.
The aim of this study was to demonstrate the lower limb alignment in knee flexion position after navigation-assisted total knee arthroplasty using the gap technique and to identify the correlative factors.
One hundred and twenty consecutive osteoarthritic knees (120 patients) were prospectively enrolled for intraoperative data collection. All TKA surgeries were performed using the navigation system (OrthoPilot™, version 4.0; B. Braun Aesculap, Tuttlingen, Germany). Before and after final prosthesis implantation, the lower limb navigation alignment in both knee extension (0°) and knee flexion (90°) position was recorded. The knee flexion alignment was divided into three groups: varus, neutral and valgus alignment. To determine the factors of the alignment in knee flexion position, preoperative demographics, radiologic and intraoperative data were obtained. Pearson's correlation (r) analysis was performed to find the correlation. The Knee Society Score and Western Ontario and McMaster Universities Osteoarthritis Index were compared between groups.
Although all postoperative extension alignment was within neutral position (between -2° and +2°), postoperative knee flexion alignment was divided into three groups: varus (≤-3°), 24 cases (20 %); neutral (between -2° and +2°), 85 cases (70.8 %) and valgus (≥+3°) alignment, 11 cases (9.2 %). There were a good correlation of alignment in knee flexion position with the rotation of femoral component relative to posterior condylar axis (r = -0.502, p = 0.000) and weak correlations with posterior femoral cut thickness (lateral condyle) (r = 0.207, p = 0.026), medial flexion (90°) gap after femoral component rotation adjustment (r = 0.276, p = 0.003). Other variables did not show correlations. There were no statistical clinical differences between varus, neutral and valgus knee flexion alignment groups.
About 30 % of the cases showed malalignment of more than 3° in knee flexion position although with neutral alignment in extension position. The knee flexion alignment had a good correlation with the rotation of femoral component relative to posterior condylar axis. Neutral alignment in knee flexion position may be adjusted by femoral component rotation especially by the use of navigation system.
IV.
本研究旨在展示采用间隙技术的导航辅助全膝关节置换术后膝关节屈曲位的下肢对线情况，并确定相关因素。
前瞻性纳入120例连续的骨关节炎膝关节患者（120例）进行术中数据收集。所有全膝关节置换手术均使用导航系统（OrthoPilot™，版本4.0；德国图特林根市贝朗蛇牌）。在最终假体植入前后，记录膝关节伸直位（0°）和膝关节屈曲位（90°）的下肢导航对线情况。膝关节屈曲对线分为三组：内翻、中立和外翻对线。为确定膝关节屈曲位对线的因素，获取术前人口统计学、放射学和术中数据。进行Pearson相关性（r）分析以找出相关性。比较各组间的膝关节协会评分和西安大略和麦克马斯特大学骨关节炎指数。
尽管所有术后伸直位对线均在中立位（-2°至+2°之间），但术后膝关节屈曲对线分为三组：内翻（≤-3°），24例（20%）；中立（-2°至+2°之间），85例（70.8%）；外翻（≥+3°）对线，11例（9.2%）。膝关节屈曲位对线与股骨组件相对于后髁轴的旋转具有良好的相关性（r = -0.502，p = 0.000），与股骨后髁截骨厚度（外侧髁）具有较弱的相关性（r = 0.207，p = 0.026），与股骨组件旋转调整后的内侧屈曲（90°）间隙具有较弱的相关性（r = 0.276，p = 0.003）。其他变量未显示相关性。内翻、中立和外翻膝关节屈曲对线组之间无统计学临床差异。
尽管伸直位对线中立，但约30%的病例在膝关节屈曲位显示超过3°的对线不良。膝关节屈曲对线与股骨组件相对于后髁轴的旋转具有良好的相关性。膝关节屈曲位的中立对线可通过股骨组件旋转进行调整，尤其是使用导航系统时。
IV级。
