Figure 15b. Hematoma of the obturator internus muscle. (a) CT scan of a patient with a type III urethral injury shows obvious asymmetry in the sizes and contours of the obturator internus muscles, an appearance compatible with a hematoma (h) of the left muscle. (b) CT scan of a patient with a RUG-proved type II urethral injury shows an extensive hematoma (h) of the obturator internus muscle. (c) CT scan of another patient shows fractures of the right pubic body (arrow) and left superior pubic ramus (arrowhead) with preserved fat planes, sharp medial margins, and nearly symmetrical sizes and contours of the obturator internus muscles; thus, no hematoma of the obturator internus muscle is present. Despite having significant pelvic fractures, the patient did not have a urethral injury.