Department of Clinical, Jining Medical University, Jining, Shandong, China.
Department of Operating Room, Affiliated Hospital of Jining Medical University, Jining, Shandong, China.
Int Orthop. 2023 Mar;47(3):735-743. doi: 10.1007/s00264-023-05689-x. Epub 2023 Jan 16.
The purpose was to investigate the effect of different degrees of valgus deformity correction on patellar position and clinical outcome in patients with valgus knees after total knee arthroplasty (TKA).
We retrospectively analyzed and followed 118 patients with valgus knees. Based on the post-operative hip-knee-ankle (HKA), patients were divided into three groups: neutral (±3°), mild (3-6°), and severe (> 6°). Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), range of motion (ROM), and Knee Society Score (KSS) were used to evaluate post-operative clinical efficacy. Also, the patellar tilt angle (ε-angle), congruence angle (θ-angle), and Insall-Salvati index (ISI) were used to represent the patellar position. Post-operative observation indicators included HKA, angle of the femur (α-angle), tibial angle (β-angle), femoral component flexion angle (γ-angle), and tibial component posterior slope angle (δ-angle).
All patients showed significant improvements in HKA, ROM, WOMAC, and KSS after operation (P < 0.001). Regarding patellar position, the ISI values decreased to varying degrees (P < 0.05). The patellar tilt angle was significantly increased in the severe valgus group compared to that in the mild valgus and neutral groups (P < 0.001). Univariate analysis showed that the degree of post-operative residual valgus was significantly affected by WOMAC, KSS, α-, ε-, and θ-angles.
Minor valgus undercorrection did not affect the short-term outcome after TKA; however, when the residual valgus angle was > 6°, the post-operative scores were significantly reduced. Inadequate valgus correction does not result in significant changes in patellar height but may increase the risk of poor patellar tracking.
探讨全膝关节置换术（TKA）后膝内翻患者不同程度外翻畸形矫正对髌骨位置和临床结果的影响。
回顾性分析 118 例膝内翻患者，根据术后髋-膝-踝角（HKA）将患者分为三组：中立位（±3°）、轻度（3-6°）和重度（>6°）。采用 Western Ontario 和 McMaster 大学骨关节炎指数（WOMAC）、关节活动度（ROM）和膝关节学会评分（KSS）评估术后临床疗效。同时，采用髌骨倾斜角（ε 角）、髌骨吻合角（θ 角）和 Insall-Salvati 指数（ISI）来表示髌骨位置。术后观察指标包括 HKA、股骨角（α 角）、胫骨角（β 角）、股骨组件屈曲角（γ 角）和胫骨组件后倾角度（δ 角）。
所有患者术后 HKA、ROM、WOMAC 和 KSS 均明显改善（P<0.001）。髌骨位置方面，ISI 值均有不同程度的降低（P<0.05）。重度内翻组的髌骨倾斜角明显高于轻度内翻组和中立组（P<0.001）。单因素分析显示，术后残余内翻角度主要受 WOMAC、KSS、α 角、ε 角和 θ 角的影响。
TKA 术后轻微的外翻未矫正不影响短期结果；但当残余外翻角度>6°时，术后评分显著降低。外翻矫正不足不会导致髌骨高度明显变化，但可能增加髌骨跟踪不良的风险。
