Radiographically Occult and Subtle Fractures: A Pictorial Review
Figure 12
Right sacral alar insufficiency fracture in a 29-year-old woman with a 9-year history of corticosteroid therapy for systemic lupus erythematous. Conventional radiographs showed normal appearance (not shown). Coronal inversion recovery MRI shows an area of hyperintensity in the right sacral ala (white arrows), centered on a linear hypointensity corresponding to the fracture line (black arrowhead).