Boux de Casson François, Angibaud Laurent, Kerveillant Florian, Nogaret Faustine, Ruffin Joris, Duporté Léonard, Giordano Gérard, Dagneaux Louis
Blue-Ortho Meylan France.
Exactech Inc Gainesville Florida USA.
J Exp Orthop. 2025 Jan 13;12(1):e70107. doi: 10.1002/jeo2.70107. eCollection 2025 Jan.
Gap-balanced total knee arthroplasty (TKA) technique relies on initial ligament evaluation, particularly in patient-specific implantation using computer-assisted technologies. This cadaveric study aimed to compare the reproducibility and reliability of medial and lateral gap measurements between manual stress testing and dynamic ligament balancer.
Initial gap acquisitions were assessed from eight cadaveric knees (four specimens) during the same navigated TKA procedure by five differently skilled surgeons (three seniors and two juniors). Medial and lateral gaps were sequentially acquired from extension to maximum knee flexion, applying manual stress prior to any bone cuts (conventional technique), and using intra-articular tensioning device placed between the tibial cut and the native femur (instrumented technique). Reproducibility was assessed using intraclass correlation coefficient (ICC), stratified by the measurement technique, the type of gaps and the operator experience. Differences in gaps (mm) between techniques were assessed using the Bland and Altmann method.
The instrumented technique showed higher ICCs than the conventional technique for medial and lateral gaps (0.87 vs. 0.60, = 0.002, and 0.92 vs. 0.25, < 0.0001, respectively), and showed no difference in ICCs between medial and lateral gap acquisitions (0.87 vs. 0.92, = 0.8). Senior surgeons achieved higher ICCs than juniors, while non-significant with both techniques. Differences in gaps between techniques increased with knee flexion angle (0.8, 2.8 and 3.5 mm at 10°, 45° and 90° of flexion angle, respectively) and decreased with the operator experience ( = 0.003).
The instrumented balancing technique offered better reproducibility than using manual valgus and varus stress, when measuring medial and lateral gaps. Tensioning devices may play a significant role in enhancing initial gap acquisition, disregarding the flexion angle and the operator experience.
Level IV (observational study involving cadaveric specimens).
间隙平衡全膝关节置换术（TKA）技术依赖于初始韧带评估，尤其是在使用计算机辅助技术进行患者特异性植入时。本尸体研究旨在比较手动应力测试和动态韧带平衡器在内侧和外侧间隙测量的可重复性和可靠性。
在同一导航TKA手术过程中，由五名技能水平不同的外科医生（三名资深医生和两名初级医生）对八个尸体膝关节（四个标本）进行初始间隙采集。在内侧和外侧间隙从伸直位依次采集至膝关节最大屈曲位时，在任何截骨之前施加手动应力（传统技术），并使用置于胫骨截骨处和天然股骨之间的关节内张紧装置（器械技术）。使用组内相关系数（ICC）评估可重复性，按测量技术、间隙类型和操作者经验进行分层。使用布兰德和奥特曼方法评估技术之间间隙（mm）的差异。
对于内侧和外侧间隙，器械技术显示出比传统技术更高的ICC值（分别为0.87对0.60，P = 0.002，以及0.92对0.25，P < 0.0001），并且在内侧和外侧间隙采集的ICC值之间没有差异（0.87对0.92，P = 0.8）。资深外科医生获得的ICC值高于初级医生，但两种技术均无显著差异。技术之间的间隙差异随膝关节屈曲角度增加（屈曲角度为10°、45°和90°时分别为0.8、2.8和3.5mm），并随操作者经验减少（P = 0.003）。
在测量内侧和外侧间隙时，器械平衡技术比使用手动内外翻应力具有更好的可重复性。张紧装置在增强初始间隙采集方面可能发挥重要作用，而不受屈曲角度和操作者经验的影响。
IV级（涉及尸体标本的观察性研究）
