Aydin Abdurrahman, Gürsu Sarper, Yapici Furkan, Gür Volkan
Department of Orthopedics and Traumatology, Düzce Akçakoca State Hospital, Düzce, TUR.
Department of Orthopedics and Traumatology, University of Health Sciences, M. S. (Metin Sabancı) Baltalimani Bone and Joint Diseases Research Hospital, Istanbul, TUR.
Cureus. 2023 Feb 16;15(2):e35066. doi: 10.7759/cureus.35066. eCollection 2023 Feb.
Traditionally, in total knee arthroplasty (TKA), it is aimed to keep the mechanical axis of the lower extremity neutral (mechanical alignment: 3° varus-valgus in the coronal plane) to improve long-term outcomes. This study aimed to assess the mid-term radiological and clinical results of patients with postoperative residual varus (more than 3° of varus) after mechanically-aligned TKA.
A total of 616 individuals who had undergone TKA for primary knee osteoarthritis between 2008 and 2013 in our tertiary care hospital were retrospectively examined. All TKAs were performed with the mechanical alignment strategy. For radiological evaluation, hip-knee-ankle (HKA) angle, knee alignment angle (KAA), mechanical medial proximal tibial angle (mMPTA), knee inclination (KI), joint line orientation angle relative to ground (JLOA-G), posterior tibial slope (PS), joint line convergence angle (JLCA) were measured. Besides, patients' latest radiographs were screened for any clue of aseptic loosening or mechanical failure. Knee Society Score (KSS) (knee and functional subgroups), and Lysholm, Oxford, and Tegner scores were used for clinical evaluation. In addition, knee flexion and extension limitations were assessed.
After applying the exclusion criteria, a minimum of five-year follow-up result of 110 patients was demonstrated. There were 101 females (92%) and nine males (8%). The mean follow-up time was 65.8 ± 6.3 months (range: 60.8-75.8 years). The mean age was 65.9 ± 7.7 years (range: 39 to 89 years). The preoperative mean mechanical axis angle of the lower extremity was 17.3° ± 7.8° (range: 13.4-43.9°), whereas it was 8.3° ± 3.6° (range: 3.2-19.8°) postoperatively. The preoperative mean flexion angle was 90.7° ± 23.8° (range: 40-130°), and the extension limitation was -2.5° ± 7.4° (range: -40-0°), whereas, postoperatively, they were 102.8° ± 15.4° (range from 40° to 150°) and -3.7° ± 7.5° (range from -40° to 0°), respectively. The latest follow-up's mean KSS knee subgroup was 67 ± 18.4 (range: 12-93), the mean KSS functional subgroup was 74 ± 23.6 (range: 20-100), the mean Lysholm score was 81.7 ± 15.7 (range:25-100), the mean Tegner score was 3.65 ± 0.99 (range: 1-5), the mean Oxford score was 37.4 ± 6.5 (range: 9-48). There was no patient with aseptic loosening or mechanical failure.
In the mid-term follow-up of patients with residual varus after mechanically-aligned TKA, satisfactory clinical and radiological results were obtained without aseptic loosening or implant failure.
传统上，在全膝关节置换术（TKA）中，目标是使下肢的机械轴保持中立（机械对线：冠状面内3°内翻-外翻）以改善长期效果。本研究旨在评估机械对线TKA术后残留内翻（内翻超过3°）患者的中期影像学和临床结果。
回顾性研究了2008年至2013年间在我们三级医疗中心因原发性膝关节骨关节炎接受TKA的616例患者。所有TKA均采用机械对线策略。对于影像学评估，测量髋-膝-踝（HKA）角、膝关节对线角（KAA）、机械性胫骨近端内侧角（mMPTA）、膝关节倾斜度（KI）、关节线相对于地面的方向角（JLOA-G）、胫骨后倾（PS）、关节线汇聚角（JLCA）。此外，对患者最新的X线片进行筛查，寻找无菌性松动或机械故障的任何线索。采用膝关节协会评分（KSS）（膝关节和功能亚组）、Lysholm评分、牛津评分和Tegner评分进行临床评估。此外，评估膝关节屈伸受限情况。
应用排除标准后，展示了110例患者至少五年的随访结果。有101名女性（92%）和9名男性（8%）。平均随访时间为65.8±6.3个月（范围：60.8 - 75.8年）。平均年龄为65.9±7.7岁（范围：39至89岁）。术前下肢平均机械轴角度为17.3°±7.8°（范围：13.4 - 43.9°），而术后为8.3°±3.6°（范围：3.2 - 19.8°）。术前平均屈曲角度为90.7°±23.8°（范围：40 - 130°），伸展受限为-2.5°±7.4°（范围：-40 - 0°），而术后分别为102.8°±15.4°（范围：40°至150°）和-3.7°±7.5°（范围：-40°至0°）。最新随访时，平均KSS膝关节亚组评分为67±18.4（范围：12 - 93），平均KSS功能亚组评分为74±23.6（范围：20 - 100），平均Lysholm评分为81.7±15.7（范围：25 - 100），平均Tegner评分为3.65±0.99（范围：1 - 5），平均牛津评分为37.4±6.5（范围：9 - 48）。没有患者出现无菌性松动或机械故障。
在对机械对线TKA术后残留内翻患者的中期随访中，获得了满意的临床和影像学结果，且无无菌性松动或植入物故障。
