Fig. 5

Twenty-two-year-old female long distance runner with sacral stress fracture which initially mimicked radicular pain (lower lumbar pain with pain/numbness in buttock) and later the pain was localized over the right sacroiliac joint. a Coronal SPECT image of the pelvic region shows intense uptake in the right lateral aspect of the sacrum. b, c Sagittal T2 STIR MR sequences left and right, respectively, performed 1 month prior to bone scan for “radicular type lumbar pain” was read as negative, but coronal pelvic T2-weighted images were not obtained. In retrospect sagittal T2 STIR image right (c) showed edema in the right sacrum (seen at the edge of the field of view only). Repeat MRI of the pelvis 1 day after bone scan showed nondisplaced right lateral sacral fracture on coronal T1 weighted images (d) with associated bone marrow edema seen in coronal T2-weighted SPAIR image (e). Athletes with lower lumbar pain and negative lumbar spine MRI would benefit from additional coronal pelvis images to exclude referred lumbar pain caused by pelvic injuries