Department of Orthopaedic Surgery, Mayo Clinic, Rochester, Minnesota.
J Arthroplasty. 2018 Apr;33(4):1231-1234. doi: 10.1016/j.arth.2017.11.012. Epub 2017 Nov 13.
Poor rotation of the tibial component is associated with unfavorable total knee arthroplasty outcomes. Some surgeons utilize the tibial tubercle (TT method), while others utilize the femoral cam (Box method) as a rotational landmark during total knee arthroplasty. Our purpose is to determine the reproducibility of 2 methods for establishing intra-operative tibial component rotation, while also comparing the effect of level of training.
Twelve surgeons positioned and sized a symmetric tibial component on 7 cadaver knees. Surgeons were allowed to utilize their preferred method for establishing tibial component rotation. Seven surgeons selected the TT method, 4 utilized the Box method, and 1 used both methods depending on the specimen. Repeat measurements were completed by each surgeon after a rest period. The differences between tibial tray positions were assessed using computer-assisted optoelectronic measurements. Intra-class correlation coefficients were calculated to determine inter-observer agreement (IOA) and intra-rater reliability (IRR).
Overall, both the Box method and the TT method demonstrated high IRR for tibial component rotation. Experienced surgeons were more consistent at establishing component rotation regardless of technique. Trainees were more consistent when utilizing the Box method (IRR 0.96, IOA 0.94) than the TT method (IRR 0.71, IOA 0.72).
Surgeon experience influences the agreement and reliability of tibial component position. For less experienced surgeons, the Box method was more effective than the TT method for consistently reproducing tibial component rotation.
胫骨组件的旋转不良与全膝关节置换术的不良结果有关。一些外科医生在全膝关节置换术中使用胫骨结节（TT 法），而另一些则使用股骨凸轮（Box 法）作为旋转标志。我们的目的是确定两种确定术中胫骨组件旋转的方法的可重复性，同时比较培训水平的影响。
12 名外科医生在 7 个尸体膝关节上定位和调整对称胫骨组件。外科医生可以选择他们喜欢的方法来确定胫骨组件的旋转。7 名外科医生选择 TT 法，4 名外科医生选择 Box 法，1 名外科医生根据标本选择两种方法。每位外科医生在休息一段时间后完成重复测量。使用计算机辅助光电测量评估胫骨托位置之间的差异。计算组内相关系数以确定观察者间一致性（IOA）和内部评分者可靠性（IRR）。
总体而言，Box 法和 TT 法在胫骨组件旋转方面均具有较高的 IRR。无论技术如何，经验丰富的外科医生在确定组件旋转方面更为一致。与 TT 法（IRR 0.71，IOA 0.72）相比，接受培训的医生在使用 Box 法（IRR 0.96，IOA 0.94）时更能一致地复制胫骨组件旋转。
外科医生的经验会影响胫骨组件位置的一致性和可靠性。对于经验较少的外科医生，Box 法比 TT 法更有效，可更一致地复制胫骨组件的旋转。
