长骨应力性骨折的MR诊断及鉴别诊断

目的 分析长骨应力性骨折的MR表现,提高对长骨应力骨折的MR诊断和鉴别诊断. 资料与方法 回顾性分析经临床病理或追踪复查证实的12例长骨应力骨折患者的MR图像. 结果 12例中股骨颈1例,股骨下段4例,胫骨上段6例,腓骨下段1例.MR均可见骨髓腔内大片长T1、长T2信号骨髓水肿,范围远较平片广泛,DWI像骨髓水肿区较T2WI更明显;并可见骨膜水肿,表现为骨皮质周围环形长T1、长T2信号;9例可见骨折线,矢状位和轴位PDWI和T2WI表现为局部骨皮质中断呈稍长T2信号,冠状位T2WI和PDWI髓腔内与骨皮质相连的横行低信号带;软组织肿胀呈弥漫性长T1、长T2信号. 结论 MRI能够更敏感地发现早期应力性骨折,为诊断和判断骨折愈合情况提供更多信息.

MR Findings in the Diagnosis of Stress Fractures of Long Bone

Objective To evaluate the role of MR imaging findings in the diagnosis of stress fracture of long bone. Methods MR imaging findings in 12 cases with stress fractures of long bone confirmed by pathology and follow-up results were reviewed respectively. Results The stress fracture was observed in the femoral neck in 1 case, in the distal femur in 4 patients, in the proximal tibia in 6 cases, and in the distal fibula in 1 case. On MR imaging, all 12 patients demonstrated diffuse long T1 and long T2 signal in the medullary cavity suggesting marrow edema, which showed more extensive on diffusion weighted imaging. Periosteoedema was seen displaying ring-shaped long T1 and long T2 signal intensity around the cortex. Fracture line found in 9 cases showed disruption of the bony cortex, which was slightly long T2 signal intensity on sagittal and axial proton density weighted imaging and T2-weighted imaging. Soft tissue swelling was also identified showing diffuse long T1 and long T2 signal intensity. Conclusions MR imaging could be a more sensitive method in the detection of the early stress fracture and provide more information for diagnosis and follow-up.