Department of Biomedical Sciences for Health, Laboratory of Applied Biomechanics, Università degli Studi di Milano, Milan, Italy; 1° Clinica Ortopedica, ASST Centro Specialistico Ortopedico Traumatologico Gaetano Pini-CTO, Milan, Italy.
Divisione di Ortopedia e Traumatologia, IRCCS Ospedale Classificato Equiparato Sacro Cuore - Don Calabria, Negrar, Italy.
J Arthroplasty. 2019 Jul;34(7):1374-1381.e1. doi: 10.1016/j.arth.2019.03.018. Epub 2019 Mar 13.
Proposed aims of patient-specific instrumentation (PSI) for total knee arthroplasty (TKA) are to improve accuracy of component alignment, while reducing blood loss and surgical time. The primary goal of this prospective, randomized, controlled, clinical trial is to verify whether PSI improves the rotational alignment of the femoral component in comparison to conventionally implanted TKA.
One-hundred thirty-three consecutive patients were assessed for eligibility. Block randomization was performed to allocated patients in the treatment (PSI) or control group. During hospital stay, surgical times were recorded, and total blood volume loss and estimated red blood cell were calculated. Two months after surgery, a computed tomography of the knee was obtained to measure femoral component rotation to the transepicondylar axis and tibial component slope.
Sixty-nine patients were enrolled. PSI did neither result in a significant improvement in femoral component rotation nor result in a reduction of outliers, as compared with conventional instrumentation. No significant improvement in terms of tibial slope, blood loss, total surgical time, and ischemia time could be identified. The number of tibial recuts required in the PSI group was significantly higher than in the control group (P = .0003).
PSI does not improve the accuracy of femoral component rotation in TKA in comparison to conventional instrumentation. Moreover, PSI did not appear to influence any of the other variables investigated as secondary goals by this study. The results of this study do not support its routine use during standard TKA.
Level I, randomized, controlled trial.
个体化截骨（PSI）在全膝关节置换术（TKA）中的目的是提高假体对线的准确性，同时减少失血量和手术时间。本前瞻性、随机、对照、临床试验的主要目的是验证PSI 是否比传统植入的 TKA 更能改善股骨假体的旋转对线。
对 133 例连续患者进行了入选评估。采用区组随机化将患者分配到治疗（PSI）或对照组。在住院期间，记录手术时间，并计算总失血量和估计的红细胞量。术后 2 个月，对膝关节进行 CT 扫描，以测量股骨假体相对于髁间轴和胫骨假体斜率的旋转。
69 例患者入组。与传统器械相比，PSI 既没有显著改善股骨假体的旋转，也没有减少离群值。在胫骨斜率、失血量、总手术时间和缺血时间方面也没有显著改善。PSI 组需要胫骨再截骨的数量明显高于对照组（P=0.0003）。
与传统器械相比，PSI 并不能提高 TKA 中股骨假体旋转的准确性。此外，PSI 似乎也没有影响本研究作为次要目标调查的其他任何变量。本研究结果不支持其在标准 TKA 中的常规使用。
I 级，随机对照试验。
