Thomaz Leonardo Dalla Giacomassa Rocha, Geist João Guilherme Brochado, Lucena Rafael De Luca De, Schwartsmann Carlos Roberto, Freitas Geraldo Luiz Schuck de, Spinelli Leandro de Freitas
Serviço de Ortopedia e Traumatologia, Santa Casa de Misericórdia de Porto Alegre, Porto Alegre, RS, Brasil.
Serviço de Ortopedia e Traumatologia, Hospital Regina, Novo Hamburgo, Porto Alegre, RS, Brasil.
Rev Bras Ortop (Sao Paulo). 2021 Apr 19;57(4):656-660. doi: 10.1055/s-0041-1726061. eCollection 2022 Aug.
To demonstrate the greater accuracy of panoramic radiographs of the lower limbs (long) in relation to short radiographs of the knee in the measurement of the mechanical axis of the lower limb after total knee arthroplasty (TKA). A retrospective study was conducted to evaluate the accuracy of long and short postoperative radiographic images of 70 patients submitted to TKA in our service. The images were analyzed at random, at different times, by three orthopedists. In all images, the mechanical axis of the limb, femur and tibia were traced and femorotibial angles (FTAs) were calculated. The intraclass correlation coefficient (ICC) was calculated to evaluate the agreement of the measurement of the inter- and intra-observer mechanical axis. It was observed that there was high intra and interobserver agreement when panoramic radiographs were used, with minimum intra and interobserver ICC of 0.89, equivalent to a very strong agreement. On short radiographs in the anteroposterior incidence (AP) of the knee, the ICC showed moderate agreement, obtaining a maximum value of 0.75. There is a significant difference in accuracy for the measurement of the mechanical axis of the lower limb, comparing long and short radiographs of the lower limb. Thus, for the proper measurement of the mechanical axis of the lower limb, we suggest the performance of long radiography in the postoperative period of TKA.
为了证明在全膝关节置换术（TKA）后测量下肢机械轴时，下肢全景（长）X线片相对于膝关节短X线片具有更高的准确性。 我们进行了一项回顾性研究，以评估在我们科室接受TKA的70例患者术后长、短X线影像的准确性。由三名骨科医生在不同时间对影像进行随机分析。在所有影像中，描绘出肢体、股骨和胫骨的机械轴，并计算股胫角（FTA）。计算组内相关系数（ICC）以评估观察者间和观察者内机械轴测量的一致性。 结果发现，使用全景X线片时，观察者间和观察者内一致性较高，观察者间和观察者内ICC最小值为0.89，相当于非常强的一致性。在膝关节前后位（AP）的短X线片上，ICC显示为中度一致性，最大值为0.75。 比较下肢长、短X线片，下肢机械轴测量的准确性存在显著差异。因此，为了正确测量下肢机械轴，我们建议在TKA术后进行长X线摄影。
