Traumatic subperiosteal pseudoaneurysm: rare cause of subperiosteal hematoma

Subperiosteal hematoma arises usually after blunt trauma to the bone. It is due to disinsertion or rupture of a muscle tendon or injury of nutrient artery of bone. Subperiosteal hematoma is a rare condition and develops mainly in the orbit because the periosteum is more loosely attached to the bone. Thus, few cases of subperiosteal hematoma in iliac bone are reported. Traumatic pseudoaneurysm develops mainly after penetrating or blunt trauma. It can be easily diagnosed by intravenous contrast computed tomography or magnetic resonance imaging by seen extravasation of contrast dye. We present a case of subperiosteal hematoma with subperiosteal pseudoaneurysm after blunt pelvic trauma in a 17-year-old adolescent boy. The pseudoaneurysm arose from a branch of superior gluteal artery, but it was not seen in the initial contrast computed tomography scan.