Faculty of Medicine, Department of Orthopaedics and Traumatology, Mugla Sitki Kocman University, 48000, Mentese, Mugla, Turkey.
Skeletal Radiol. 2019 Sep;48(9):1427-1434. doi: 10.1007/s00256-019-03212-1. Epub 2019 Apr 10.
The aim of this study was to evaluate the sensitivity and specificity of radiographs in identifying incomplete atypical femoral fractures and to determine interobserver and intra-observer reliability.
Anterior-posterior and lateral radiographs of 10 femurs with incomplete atypical femoral fractures confirmed using bone scintigraphy and magnetic resonance imaging, and 40 femurs without incomplete atypical femoral fractures confirmed using bone scintigraphy, were reviewed by 4 orthopedic surgeons and 4 radiology specialists. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were calculated to determine a diagnosis of incomplete atypical femoral fractures. Interobserver reliability was measured using Fleiss' kappa value, and intra-observer reliability was ascertained using Cohen's kappa statistic.
Mean sensitivity, specificity, accuracy, and the positive and negative predictive values were found to be 89, 89, 89, 67, and 97% respectively, in diagnosing incomplete atypical femoral fractures using radiographs. Interobserver reliability was found to be at a good level (Fleiss' kappa = 0.66, standard error = 0.03, 95% confidence interval = 0.61-0.71). Intra-observer Cohen's kappa values ranged from 0.53 to 0.91.
The use of radiography was satisfactory in identifying incomplete atypical femoral fractures, and the level of interobserver agreement was found to be good. As radiographs are associated with low positive predictive values, an advanced imaging method should be used when an increase in femoral cortical thickness is the only contributory factor to suspicion of an incomplete atypical femoral fracture.
本研究旨在评估 X 线片在识别不完全型股骨骨折中的敏感性和特异性，并确定观察者间和观察者内的可靠性。
回顾性分析 10 例经骨闪烁成像和磁共振成像证实的不完全型股骨骨折和 40 例经骨闪烁成像证实的无不完全型股骨骨折的股骨的前后位和侧位 X 线片，由 4 名骨科医生和 4 名放射科专家进行阅片。计算诊断不完全型股骨骨折的敏感性、特异性、准确性、阳性预测值和阴性预测值。采用 Fleiss'kappa 值评估观察者间可靠性，采用 Cohen's kappa 统计量评估观察者内可靠性。
X 线片诊断不完全型股骨骨折的平均敏感性、特异性、准确性、阳性预测值和阴性预测值分别为 89%、89%、89%、67%和 97%。观察者间可靠性较好（Fleiss'kappa=0.66，标准误=0.03，95%置信区间=0.61-0.71）。观察者内 Cohen's kappa 值范围为 0.53-0.91。
X 线片在识别不完全型股骨骨折方面表现令人满意，观察者间的一致性水平较好。由于 X 线片的阳性预测值较低，当股骨皮质增厚是唯一提示不完全型股骨骨折的因素时，应使用高级影像学方法。
