MRI Patterns in the Acute or Subacute Stage of Osteoporotic Vertebral Fractures / 대한척추외과학회지

ABSTRACT

STUDY DESIGN: This is a retrospective radiologic study OBJECTIVES: The aim of this study is to analyze the signals and configurations of the MRI findings of osteoporotic vertebral fractures and the clinical consequences of each type of the MRI findings. SUMMARY OF THE LITERATURE REVIEW There have been some reports that have focused on the MR findings for the differentiation of osteoporotic and metastatic fractures, but there are few reports on the characteristics of the early stage of osteoporotic vertebral fractures. MATERIALS AND METHODS: From July 2002 to April 2008, the MRI findings and medical records of 97 patients who were diagnosed with acute or subacute osteoporotic vertebral fractures and who were followed-up for more than 1 year were analyzed. The patients with minor trauma within 3 months before obtaining MRIs and they had decreased bone density were included in this study. Those with fractures due to severe trauma or pathologic causes or normal bone density were excluded. Three spine surgeons evaluated, at three times per each surgeon, the T1-weighted, T2-weighted and fat suppression T1-enhanced sagittal images for the signal of the vertebral body bone marrow and the type of the intravertebral body lesion shape. The relationships between the type of MRI findings and the time from the trauma and the follow up clinical consequences were analyzed. RESULTS: The MRI patterns of 97 patients with 111 fractures of the vertebrae were divided into three types. There were 56 cases of Type I (50.5%), which was defined as diffuse typical signal intensity in the vertebral body, 39 cases (35.1%) of Type II, which was defined as geographic low signal in the center of the vertebral body with typical signal changes, and 16 cases (14.4%). of type III, which was defined as atypical signal intensity or a shape of lesion that did not correspond to type 1 nor type 2. The average time from trauma was 10.8+/-19.0days (0~90) for type I, 19.1+/-24.9days (0~90) for type III and 37.5+/-31.1days (0~90) for type III, which showed differences among each types (p<0.001). CONCLUSIONS: The analysis of the relationship between the time from trauma and the signal intensity and the type of lesion on MRI examination revealed that the low signal intensity in the typical vertebral body signal or an atypical signal or shape were poor prognostic factors of osteoporotic vertebral fracture