The appearance of the piriformis muscle syndrome in computed tomography and magnetic resonance imaging. A case report and review of the literature. The piriformis syndrome (PS) is a controversial cause of hip pain because of the lack of objective findings to support the diagnosis. Computed tomography (CT) and magnetic resonance (MR) imaging revealed PS in a 27-year-old woman. This case may be one of the first reports in the literature on a piriformis muscle enlargement documented by CT and MR imaging. 