State Key Laboratory of Pharmaceutical Biotechnology, Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, 321 Zhongshan Road, Nanjing, 210008, Jiangsu, PR China.
Branch of National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, Nanjing, Jiangsu, PR China.
BMC Surg. 2024 Aug 14;24(1):232. doi: 10.1186/s12893-024-02524-x.
Gap tension is an important factor influencing the clinical outcomes of total knee arthroplasty (TKA). Traditional mechanical alignment (MA) places importance on neutral alignment and often requires additional soft tissue releases, which may be related to patient dissatisfaction. Conversely, the functional alignment requires less soft tissue release to achieve gap balance. Conventional gap tension instruments present several shortcomings in practice. The aim of this study is to introduce a new gap balancing technique with FA using the modified spacer-based gap tool and the MAKO robotic arm system.
A total of 22 consecutive patients underwent primary TKA using the MAKO robotic arm system. The gap tension was assessed and adjusted with the modified spacer-based gap tool during the operation. Patient satisfaction was evaluated post-operatively with a 5-point Likert scale. Clinical outcomes including lower limb alignment, Knee Society Score (KSS) and Western Ontario and McMaster Universities Arthritis Index (WOMAC) were recorded before surgery, 3 months and 1 year after surgery.
The range of motion (ROM) was significantly increased (p < 0.001) and no patients presented flexion contracture after the surgery. KSS and WOMAC score were significantly improved at 3 months and 1 year follow-up (p < 0.001 for all). During the surgery, the adjusted tibial cut showed more varus than planned and the adjusted femoral cut presented more external rotation than planned (p < 0.05 for both). The final hip-knee-ankle angle (HKA) was also more varus than planned (p < 0.05).
This kind of spacer-based gap balancing technique accompanied with the MAKO robotic arm system could promise controlled lower limb alignment and improved functional outcomes after TKA.
间隙张力是影响全膝关节置换术（TKA）临床效果的一个重要因素。传统的机械对线（MA）重视中立对线，通常需要额外的软组织松解，这可能与患者不满意有关。相反，功能对线需要较少的软组织松解来实现间隙平衡。传统的间隙张力仪器在实际应用中存在一些缺点。本研究旨在介绍一种新的间隙平衡技术，即使用改良的基于间隔器的间隙工具和 MAKO 机器人臂系统进行 FA。
共 22 例连续患者接受 MAKO 机器人臂系统行初次 TKA。在手术过程中，使用改良的基于间隔器的间隙工具评估和调整间隙张力。术后采用 5 分 Likert 量表评估患者满意度。记录术前、术后 3 个月和 1 年的下肢对线、膝关节协会评分（KSS）和西部安大略省和麦克马斯特大学关节炎指数（WOMAC）。
术后患者的活动范围（ROM）明显增加（p<0.001），无患者出现膝关节屈曲挛缩。术后 3 个月和 1 年随访时，KSS 和 WOMAC 评分均显著改善（均 p<0.001）。在手术过程中，调整后的胫骨截骨面显示出比计划更大的内翻，调整后的股骨截骨面显示出比计划更大的外旋（均 p<0.05）。最终的髋膝踝角（HKA）也比计划更内翻（p<0.05）。
这种基于间隔器的间隙平衡技术与 MAKO 机器人臂系统相结合，可以保证 TKA 后下肢对线的控制和功能结果的改善。
