Corin Ltd, Raynham, MA, USA.
Gundersen Health System, Viroqua, WI, USA.
Knee Surg Sports Traumatol Arthrosc. 2022 Mar;30(3):939-947. doi: 10.1007/s00167-021-06482-2. Epub 2021 Feb 12.
Achieving a balanced knee is accepted as an important goal in total knee arthroplasty; however, the definition of ideal balance remains controversial. This study therefore endeavoured to determine: (1) whether medio-lateral gap balance in extension, midflexion, and flexion are associated with improved outcome scores at one-year post-operatively and (2) whether these relationships can be used to identify windows of optimal gap balance throughout flexion.
135 patients were enrolled in a multicenter, multi-surgeon, prospective investigation using a robot-assisted surgical platform and posterior cruciate ligament sacrificing gap balancing technique. Joint gaps were measured under a controlled tension of 70-90 N from 10°-90° flexion. Linear correlations between joint gaps and one-year KOOS outcomes were investigated. KOOS Pain and Activities of Daily Living sub-scores were used to define clinically relevant joint gap target thresholds in extension, midflexion, and flexion. Gap thresholds were then combined to investigate the synergistic effects of satisfying multiple targets.
Significant linear correlations were found throughout extension, midflexion, and flexion. Joint gap thresholds of an equally balanced or tighter medial compartment in extension, medial laxity ± 1 mm compared to the final insert thickness in midflexion, and a medio-lateral imbalance of less than 1.5 mm in flexion generated subgroups that reported significantly improved KOOS pain scores at one year (median ∆ = 8.3, 5.6 and 2.8 points, respectively). Combining any two targets resulted in further improved outcomes, with the greatest improvement observed when all three targets were satisfied (median ∆ = 11.2, p = 0.002).
Gap thresholds identified in this study provide clinically relevant and achievable targets for optimising soft tissue balance in posterior cruciate ligament sacrificing gap balancing total knee arthroplasty. When all three balance windows were achieved, clinically meaningful pain improvement was observed.
Level II.
在全膝关节置换术中，实现膝关节平衡被认为是一个重要目标；然而，理想平衡的定义仍然存在争议。因此，本研究旨在确定：（1）在伸直、中弯和屈膝位时，内外侧间隙平衡是否与术后 1 年的改善结果评分相关；（2）这些关系是否可以用于确定整个屈膝过程中最佳间隙平衡的窗口。
本研究共纳入了 135 例患者，这些患者来自多中心、多外科医生的前瞻性研究，使用机器人辅助手术平台和后交叉韧带牺牲间隙平衡技术。在 70-90 N 的受控张力下，从 10°-90°屈膝位测量关节间隙。研究了关节间隙与术后 1 年 KOOS 结果之间的线性相关性。使用 KOOS 疼痛和日常生活活动亚量表来定义伸直、中弯和屈膝位的临床相关关节间隙目标阈值。然后将关节间隙阈值结合起来，以研究满足多个目标的协同作用。
在整个伸直、中弯和屈膝位都发现了显著的线性相关性。在伸直位时，内侧间隙的平衡或更紧、内侧松弛度±1mm 与最终插入厚度相比、屈膝位时的内外侧间隙不平衡小于 1.5mm 时，可产生报告在术后 1 年时 KOOS 疼痛评分显著改善的亚组（中位数差异分别为 8.3、5.6 和 2.8 分）。组合任何两个目标都会进一步改善结果，当满足所有三个目标时，观察到的改善最大（中位数差异为 11.2 分，p=0.002）。
本研究确定的间隙阈值为后交叉韧带牺牲间隙平衡全膝关节置换术中优化软组织平衡提供了具有临床意义和可实现的目标。当达到所有三个平衡窗口时，观察到了有临床意义的疼痛改善。
2 级。
