摘要：探讨骶骨衰竭骨折的影像学特点及其鉴别诊断。方法：回顾性分析45例经随访证实的骶骨机能不全性骨折的影像学表现。45例中42例行MRI检查，45例行CT检查，16例行X线检查，12例行ECT检查。结果：平片检查共16例，发现阳性仅6例。阳性率37.5%。阳性表现为线样透亮影伴边缘骨质硬化。CT检查45例，发现阳性骨折线共25例，骨折线边缘骨质呈条带状硬化表现，阳性率55.6%。另外影像特点表现为局部显示为不均匀骨质密度，或者混杂密度。 MRI检查42例，均表现为大片状长T1长T2骨髓水肿信号，无明确的边界，范围较广，阳性率达100%。其中34例可见线样骨折线影，阳性率达81%，26例为T1WI和T2WI均为低信号。8例T1WI呈线样低信号，T2WI呈线样高信号特点。骨折线均平行于骶髂关节面。结论：骶骨机能不全性骨折有明显的影像特征，尤其是MRI检查，可显著提高影像诊断准确率， 避免不必要的过度检查和过度治疗。
Objective: To investigate the imaging features and differential diagnosis of sacral insufficiency fractures. Methods: The imaging findings of 45 patients with sacral insufficiency fractures confirmed by imaging examination and follow-up were analyzed retrospectively. Among the 45 patients, 42 underwent MRI, 45 underwent CT, 16 underwent X-ray, and 12 underwent ECT. Results: The positive rate of X-ray was 37.5% featured by linear radiolucency accompanying by osteosclerosis. The positive rate of CT was 55.6% featured by linear radiolucency combined with marginal sclerosis. Other cases showed sacrum inhomogeneous or mixed bony density. The positive rate of MRI was 100% with the character of massive patchy bone marrow edema in sacrum. Among them, 81% of cases showed typical fracture line, 26 cases showed low signal fracture line on both T1WI and T2WI. 8 cases showed low signal fracture line on T1WI and high signal on T2WI. Conclusion: The imaging diagnosis of sacral insufficiency fracture has certain characteristics, especially MRI , which can improve the accurate diagnosis rate obviously and to avoid the excessive examination and thearpy.