Figure 4b. Increasing pain and fever in a 5-year-old boy with a 2-week history of gastrointestinal distress. CT was performed to "r/o [rule out] appy [appendectomy] vs. abscess." (a) CT scan shows an ill-defined mass (H) within the mesentery. The abnormality extends to the mesenteric root. A large amount of free fluid (F) is present, mainly within the pelvis. The anterior ends of several ribs were irregular and probably fractured. (b) CT scan shows a fracture of the left anterior sixth rib (arrow). The slight expansion of the right anterior sixth rib (?) distinguishes this rib from the adjacent ribs and was likely due to previous fracture. At surgery, a mesenteric tear with a large hematoma was found. Child abuse was subsequently substantiated.