Parish Cooper R, Lovro Luke R, Deckard Evan R, Meneghini R Michael
Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN, USA.
Indiana Joint Replacement Institute, Indianapolis, IN, USA.
Arthroplast Today. 2025 Jul 29;34:101782. doi: 10.1016/j.artd.2025.101782. eCollection 2025 Aug.
Instability remains a leading cause of revision total knee arthroplasty (TKA). However, whether a full component revision (FCR) or an isolated tibial insert exchange (ITIE) is indicated remains complicated with conflicting evidence. This study compared the outcomes of patients undergoing ITIE vs FCR for instability.
A retrospective review was performed on 172 consecutive revision TKAs for global or isolated flexion instability. Diagnosis of symmetric global instability vs isolated flexion instability was based on pre-revision examination in the clinic and confirmed by rigorous numerical flexion and extension gap measurements intraoperatively. Patient-reported outcome measures and associated clinically relevant thresholds were evaluated using a significance level of 0.05.
There were 144 patients who underwent FCR for flexion instability, while 28 underwent ITIE for global instability. While not statistically significant, a greater percentage of FCR patients met the minimal clinically important difference threshold for the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (69 vs 38%; = .11); while there was no difference in minimal clinically important difference between FCR and ITIE in other patient-reported outcome measures ( ≥ .28). Patients were "very satisfied or satisfied" in 58% of the ITIE group vs 56% of the FCR group ( = .51).
Study results demonstrate that ITIE can be successful after revision TKA given the specific indication of symmetric global instability with well-fixed and well-positioned components. However, FCR is preferred in the case of flexion instability and the surgeon must be vigilant in their specific instability etiology within each patient.
III.
膝关节置换术后不稳定仍然是翻修手术的主要原因。然而，对于是进行全组件翻修（FCR）还是单独进行胫骨衬垫置换（ITIE），由于证据相互矛盾，情况仍然复杂。本研究比较了因不稳定而接受ITIE与FCR的患者的治疗结果。
对172例连续的因整体或单纯屈曲不稳定而进行翻修的全膝关节置换术进行回顾性研究。对称的整体不稳定与单纯屈曲不稳定的诊断基于术前临床检查，并通过术中严格的屈伸间隙数值测量得以证实。使用0.05的显著性水平评估患者报告的结局指标及相关的临床相关阈值。
144例患者因屈曲不稳定接受了FCR，28例患者因整体不稳定接受了ITIE。虽然无统计学意义，但FCR患者中达到关节置换膝关节损伤和骨关节炎结局评分最小临床重要差异阈值的比例更高（69%对38%；P = 0.11）；而在其他患者报告的结局指标中，FCR和ITIE之间的最小临床重要差异无差异（P≥0.28）。ITIE组58%的患者“非常满意或满意”，FCR组为56%（P = 0.51）。
研究结果表明，对于组件固定良好且位置良好的对称整体不稳定的特定指征，翻修全膝关节置换术后ITIE可以成功。然而，在屈曲不稳定的情况下，FCR是首选，并且外科医生必须对每个患者的特定不稳定病因保持警惕。
III级。
