Computed tomography (CT) is considered the gold standard for femoral version measurement. However, recent data have shown magnetic resonance imaging (MRI) as another modality to measure femoral version. This study aimed to correlate MRI and CT femoral version measurements in patients presenting with a femoroacetabular impingement (FAI)-related complaint. Patients (18–35 years old) who presented to the hip preservation clinic and radiology department with a suspected FAI diagnosis from 26 December 2018 to 4 March 2020 were included. All patients had a CT and MRI of the hip, with images including both hips and knees, as per our institution’s protocol for possible hip preservation surgery. Patients were excluded if they were missing views of the knees, or if they had a history or imaging appearance of any condition affecting femoral version at the femoral head (e.g. slipped capital femoral epiphysis). Femoral version was measured by three reviewers. Fifty-eight patients were included, and 36 (62%) were female. Femoral version averaged 6.1° ± 11.8° on CT and 6.5° ± 10.8° on MRI. A strong positive correlation was reported between the two imaging modalities (r: 0.81; P < 0.001). Inter-rater reliability among the three reviewers was excellent and statistically significant for measurements on both MRI [intraclass correlation coefficient (ICC): 0.95; 95% CI: 0.85, 0.99; P < 0.001] and CT (ICC: 0.97; 95% CI: 0.92, 0.99; P < 0.001). Our finding suggests that MRI is a sufficient method for measuring femoral version to determine disease etiology and treatment progression. To avoid exposing patients to ionizing radiation, physicians should not obtain CT scans to evaluate femoral version.

中文翻译：

---

股骨髋臼撞击相关主诉患者的 CT 和磁共振成像研究股骨倒角测量的相关性

计算机断层扫描 (CT) 被认为是股骨前倾测量的金标准。然而，最近的数据显示磁共振成像 (MRI) 是另一种测量股骨前倾的方式。本研究旨在关联股骨髋臼撞击 (FAI) 相关主诉患者的 MRI 和 CT 股骨倒角测量值。纳入了 2018 年 12 月 26 日至 2020 年 3 月 4 日期间到髋关节保护门诊和放射科诊断为疑似 FAI 的患者（18-35 岁）。根据我们机构可能进行的髋关节保留手术方案，所有患者均进行了髋关节 CT 和 MRI 检查，图像包括髋关节和膝关节。如果患者无法看到膝盖，则被排除在外，或者他们是否有任何影响股骨头处股骨前倾的病症的病史或影像学表现（例如股骨头骨骺滑脱）。股骨版本由三位评论者测量。纳入了 58 名患者，其中 36 名 (62%) 为女性。股骨版本在 CT 上平均为 6.1° ± 11.8°，在 MRI 上平均为 6.5° ± 10.8°。据报道，两种成像方式之间存在很强的正相关性 (r: 0.81；P < 0.001)。三位评价者之间的评分者间可靠性非常好，并且对于两个 MRI [组内相关系数 (ICC)：0.95；95% 置信区间：0.85、0.99；P < 0.001] 和 CT（ICC：0.97；95% CI：0.92、0.99；P < 0.001）。我们的发现表明，MRI 是测量股骨前倾角以确定疾病病因和治疗进展的充分方法。