Ferlic Peter Wilhelm, Runer Armin, Seeber Christopher, Thöni Maria, Seitlinger Gerd, Liebensteiner Michael Christian
Department of Orthopaedic Surgery, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria.
Department of Radiology, Medical University of Innsbruck, Innsbruck, Austria.
Int Orthop. 2018 Jun;42(6):1227-1231. doi: 10.1007/s00264-017-3598-8. Epub 2017 Aug 14.
De-rotational osteotomies are indicated in patients with pathologic femoral torsion. However, there is disagreement whether an osteotomy should be performed proximally or distally. Conventionally only the total torsion is measured, which does not allow differentiation between a torsional deformity located in the proximal or distal metaphysis or the diaphysis. The aim of this study is to validate a new multi-level measurement protocol for evaluation of the magnitude of torsion of the respective femoral segments in CT.
The torsional profile of 30 femora was evaluated in CT scans. For separate measurements of the torsion of the metaphysis and the diaphysis, four axes where determined: one through the femoral neck, a second determined by the midpoint of the femoral shaft and the lesser trochanter, a third determined by a tangent dorsal to the popliteal surface, and a fourth axis posterior to the condyles. The total femoral torsion was measured between the first and the fourth axis, proximal torsion between the first and the second, mid torsion between the second and the third, and distal torsion between the third and the fourth axis. Four investigators performed all measurements independently and intra-class correlation coefficients (ICC) were calculated to evaluate intra- and inter-rater reliability.
Average total femoral torsion was 22.6 ± 8.7°, proximal torsion 47.7 ± 10.6°, mid torsion -33.4 ± 9.9°, and distal torsion 8.3 ± 3.2°. Intra-rater ICC ranged between 0.504 and 0.957 and inter-rater ICC between 0.643 and 0.992. The majority of the ICC were graded as "almost perfect" and some as "substantial" agreement.
Evaluation of the segmental torsion of the femur allows in-depth analysis of femoral alignment. High reliability was shown for this measuring method in computed tomography, which can be deployed when studying interdependencies between joint pathologies and torsional deformities or when planning the site for an osteotomy.
Level III.
病理性股骨扭转患者需要进行去旋转截骨术。然而，对于截骨术应在近端还是远端进行存在分歧。传统上仅测量总扭转度，这无法区分位于近端或远端干骺端或骨干的扭转畸形。本研究的目的是验证一种新的多层次测量方案，用于评估CT中各股骨段的扭转程度。
在CT扫描中评估30个股骨的扭转情况。为分别测量干骺端和骨干的扭转，确定了四个轴：一个通过股骨颈，第二个由股骨干中点和小转子确定，第三个由腘面背侧切线确定，第四个轴位于髁后方。测量第一和第四轴之间的总股骨扭转度，第一和第二轴之间的近端扭转度，第二和第三轴之间的中段扭转度，以及第三和第四轴之间的远端扭转度。四名研究人员独立进行所有测量，并计算组内相关系数（ICC）以评估评分者内和评分者间的可靠性。
平均总股骨扭转度为22.6±8.7°，近端扭转度为47.7±10.6°，中段扭转度为-33.4±9.9°，远端扭转度为8.3±3.2°。评分者内ICC在0.504至0.957之间，评分者间ICC在0.643至0.992之间。大多数ICC被评为“几乎完美”，有些被评为“实质性”一致。
评估股骨的节段性扭转有助于深入分析股骨对线情况。该测量方法在计算机断层扫描中显示出高可靠性，可在研究关节病变与扭转畸形之间的相互关系或规划截骨部位时使用。
三级。
