Presence of extraluminal air and free fluid after blunt abdominal trauma have a high sensitivity and specificity of bowel perforation. Thickened bowel loop with adjacent extraluminal air focus can point to the site of perforation. 

At least one-half of injuries to hollow viscera involve the small bowel, followed in frequency by the colon and stomach. The segments affected most commonly are the proximal jejunum (distal to the ligament of Treitz) and the distal ileum (proximal to the ileocecal valve).