股骨疲劳性骨折采用CT、MRI诊断的价值及影像学特点分析

Diagnostic value and imaging characteristics of CT and MRI in fatigue fracture of the femur

目的分析股骨疲劳性骨折的特点,对比采用CT、磁共振成像(MRI)诊断的价值以及影像学特点。方法80例疑似股骨疲劳性骨折患者,均进行MRI、CT检查。以关节镜检查结果作为诊断金标准,对比MRI、CT诊断的准确率、灵敏度、特异度、阳性预测值、阴性预测值;分析MRI、CT的影像学特点。结果以关节镜检查结果作为诊断金标准,80例疑似股骨疲劳性骨折患者中,阳性40例,阴性40例。MRI检查诊断阳性41例,阴性39例;CT检查诊断阳性42例,阴性38例。MRI诊断的准确率91.25%、灵敏度92.50%、特异度90.00%、阳性预测值90.24%、阴性预测值92.31%均高于CT诊断的47.50%、50.00%、45.00%、47.62%、47.37%,差异具有统计学意义(P<0.05)。影像学特点:CT检查:有明显的层状骨膜增生/花边样骨膜增生,部分患者可见骨折线、骨痂形成、不同程度髓腔密度增高。MRI检查:有低信号骨折线,呈现出不等线/片状特征,部分患者有节腔内积液,部分患者呈现出清晰骨折线,低信号T2WI,部分患者呈软组织/骨挫伤水肿,软组织高信号T2WI,骨挫伤低信号T1WI。结论股骨疲劳性骨折采取CT、MRI诊断均具有价值,对比整体诊断价值以及影像学特点,MRI检查具有更高的诊断效能,是此类骨折检查的优选方式。

Objective To analyze the characteristics of fatigue fractures of the femur and compare the diagnostic value and imaging characteristics of CT and magnetic resonance imaging(MRI).Methods MRI and CT examinations were performed in 80 patients with suspected fatigue fractures of the femur.Arthroscopic findings were used as the gold standard to compare the diagnostic accuracy,sensitivity,specificity,positive predictive value and negative predictive value of MRI and CT;the imaging characteristics of MRI and CT were analyzed.Results Using arthroscopic findings as the gold standard for diagnosis,40 cases were positive and 40 cases were negative among 80 patients with suspected fatigue fractures of the femur.MRI diagnosed 41 positive cases and 39 negative cases;CT diagnosed 42 positive cases and 38 negative cases.The diagnostic accuracy,sensitivity,specificity,positive predictive value and negative predictive value of MRI were 91.25%,92.50%,90.00%,90.24%and 92.31%,which were higher than 47.50%,50.00%,45.00%,47.62%and 47.37%of CT,and the differences were statistically significant(P<0.05).Imaging features:CT examination:there was obvious laminar periosteal hyperplasia/lace-like periosteal hyperplasia,some patients showed fracture lines,bone crust formation,and different degrees of increased density in the medullary cavity.MRI examination:there were low-signal fracture lines showing unequal linear/lamellar features,some patients had intra-segmental fluid,some patients showed clear fracture lines,low-signal T2WI,some patients showed soft tissue/bone contusion edema,soft tissue highsignal T2WI,and bone contusion low-signal T1WI.Conclusion CT and MRI diagnosis of fatigue fracture of the femur are valuable.Compared with the overall diagnostic value and imaging characteristics,MRI examination has higher diagnostic efficiency and is the preferred method for this type of fracture.