Objective: To investigate the short-term effectiveness of novel computer navigation system (Knee 3 software; Brainlab, Germany) assisted total knee arthroplasty (TKA).
Methods: Between July 2020 and December 2020, 19 patients underwent unilateral TKA assisted with Knee 3 software. There were 4 males and 15 females. The mean age was 66.3 years (range, 52-79 years). Eighteen patients were diagnosed with osteoarthritis and 1 patient with rheumatoid arthritis. Sixteen patients had varus knees and 3 patients had valgus knees. Preoperative Western Ontario and McMaster University Osteoarthritis Index (WOMAC) pain, stiffness, function, and total scores were 12.4±3.4, 2 (1, 4), 22 (18, 29), and 37 (29, 43), respectively. Intraoperatively, the medial and lateral gaps in knee extension and in 90° of knee flexion were recorded. The operation time, intraoperative blood loss, blood transfusion, and complications were recorded. The hip-knee-ankle angle (HKA), lateral distal femoral angle, and medial proximal tibial angle were measured to evaluate lower limb alignment and prostheses's alignment using X-ray films at 6 weeks after operation. Patient's satisfaction rate and WOMAC pain, stiffness, function, and total scores were investigated.
Results: Eighteen patients (94.7%) had medial- lateral gap balancing in knee extension, 18 patients (94.7%) had medial-lateral gap balancing in 90° of knee flexion, 19 patients (100%) had medial gap balancing between knee extension and 90° of knee flexion, and 18 patients (94.7%) had lateral gap balancing between knee extension and 90° of knee flexion. The mean operation time was 126 minutes (range, 100-200 minutes). The mean intraoperative blood loss was 205 mL (range, 100-400 mL). Patients were followed up 4-8 months, with an average of 6.2 months. Postoperative complications included 1 deep vein thrombosis of lower extremities and 1 cerebral infarction. X-ray films showed that the mean HKA, lateral distal femoral angle, and medial proximal tibial angle were 179.8° (range, 178°-182°), 83.5° (range, 80°-87°), and 89.5° (range, 87°-93°), respectively. At last follow-up, WOMAC pain, stiffness, function, and total scores were 3.6±1.9, 0 (0, 2), 4 (2, 6), and 9 (5, 10), respectively, which improved when compared with preoperative scores ( P<0.05). Twelve patients were very satisfied with the operation results and 7 patients were satisfied with the operation results. The overall satisfaction rate was 100%.
Conclusion: Knee 3 software can help to obtain good gap balancing and optimal lower limb alignment, with high patient's satisfaction and good short-term effecectiveness.
目的: 探讨新型计算机导航系统（Knee 3 软件；Brainlab 公司，德国）辅助人工全膝关节置换术（total knee arthroplasty，TKA）的早期疗效。.
方法: 2020 年 7 月—12 月，采用 Knee 3 软件辅助 19 例（19 膝）TKA。男 4 例，女 15 例；年龄 52～79 岁，平均 66.3 岁。骨关节炎 18 例，类风湿性关节炎 1 例。膝关节内翻畸形 16 例，外翻畸形 3 例。术前美国西部 Ontario 与 McMaster 大学骨关节炎指数（WOMAC）疼痛、僵硬、功能评分分别为（12.4±3.4）、2（1，4）、22（18，29）分，总分 37（29，43）分。术中测试伸膝位及屈膝 90° 位内、外侧间隙，评估是否达间隙平衡。记录手术时间、术中出血量、术后输血和手术并发症发生情况。术后 6 周 X 线片测量髋-膝-踝角（hip-knee-ankle angle，HKA）、股骨远端外侧角和胫骨近端内侧角，评价下肢力线和假体对线。采用 WOMAC 疼痛、僵硬和功能评分评价膝关节疼痛及功能，患者自评手术满意度。.
结果: 术中测量显示 18 例（94.7%）患者达伸膝位内、外侧间隙平衡，18 例（94.7%）达屈膝 90° 位内、外侧间隙平衡，19 例（100%）达伸膝位和屈膝 90° 位内侧间隙平衡，18 例（94.7%）达伸膝位和屈膝 90° 位外侧间隙平衡。手术时间 100～200 min，平均 126 min。术中出血量 100～400 mL，平均 205 mL。术后患者均获随访，随访时间 4～8 个月，平均 6.2 个月。术后发生下肢远端深静脉血栓形成 1 例，脑梗死 1 例。X 线片测量示 HKA 178°～182°，平均 179.8°；股骨远端外侧角 80°～87°，平均 83.5°；胫骨近端内侧角 87°～93°，平均 89.5°。末次随访时，WOMAC 疼痛、僵硬和功能评分分别为（3.6±1.9）、0（0，2）、4（2，6）分，总分 9（5，10）分，均较术前改善（ P<0.05）。患者自评手术满意度，12 例达非常满意、7 例满意，总体满意率达 100%。.
结论: Knee 3 软件辅助 TKA 有助于获得良好膝关节平衡和理想下肢力线，早期疗效较好，患者满意度高。.
Keywords: Computer navigation system; Knee 3 software; gap balancing; lower limb alignment; total knee arthroplasty.