This article determines the accuracy and reliability of dual-energy computed tomography (DECT) with metal artifact reduction (MAR) in the evaluation of femoral component rotation after total knee arthroplasty (TKA), in comparison with conventional CT images. A total of 49 patients (mean age, 69 years; 42 women) who underwent TKA between January 2019 and March 2020 were retrospectively enrolled. Femoral component rotation, including the anatomic and surgical transepicondylar axes, was evaluated with preoperative conventional CT and postoperative conventional CT and DECT with MAR. Surgical femoral component rotation was also assessed as a reference standard. Accuracy was assessed using paired t-test, and inter- and intraobserver reliability using intraclass correlation coefficients (ICCs) based on postoperative conventional CT and DECT with MAR. Clinical outcomes were evaluated using the Knee Society objective and functional scores. Accuracy of femoral component rotation was not significantly different from that of surgical rotation with both conventional CT and DECT with MAR. However, inter- and intraobserver reliability were better for DECT with MAR (ICC: 0.953–0.966) than for conventional CT (ICC: 0.641–0.749). The Knee Society objective and functional scores improved 1 year postoperatively.

Conclusion DECT with MAR showed accurate and more reliable results than did conventional CT in the evaluation of femoral component rotation after TKA.

本文与传统 CT 图像相比，确定了双能计算机断层扫描 (DECT) 和金属伪影减少 (MAR) 在评估全膝关节置换术 (TKA) 后股骨假体旋转方面的准确性和可靠性。回顾性纳入 2019 年 1 月至 2020 年 3 月期间接受 TKA 的 49 例患者（平均年龄 69 岁；42 名女性）。股骨假体旋转，包括解剖和手术经上髁轴，通过术前常规 CT 和术后常规 CT 和 DECT with MAR 进行评估。外科股骨假体旋转也作为参考标准进行评估。使用配对t评估准确性-使用基于术后常规 CT 和 DECT 与 MAR 的组内相关系数 (ICC) 进行测试以及观察者间和观察者内的可靠性。使用膝关节协会目标和功能评分来评估临床结果。股骨假体旋转的准确性与传统 CT 和 DECT with MAR 的手术旋转没有显着差异。然而，DECT 与 MAR 的观察者间和观察者内部可靠性（ICC：0.953-0.966）优于传统 CT（ICC：0.641-0.749）。术后一年膝关节协会客观和功能评分有所改善。

结论 DECT 结合 MAR 在评估 TKA 后股骨假体旋转方面比常规 CT 具有更准确、更可靠的结果。