A sudden deceleration causes bruising of the chest and abdominal walls by the seatbelt. As well as being visible on clinical examination, the seatbelt sign is visible as fat stranding on trauma CT. A careful inspection of signs of small bowel and mesenteric injury secondary to blunt trauma should follow. The signs seen in this particular study include:

• free fluid with a gradient indicating hemoperitoneum
• fluid within the leaves of the mesentery
• bowel wall thickening and hypoenhancement - likely due to bowel ischemia because of shearing of mesenteric vessels

In this case, a conservative management path was followed with no clinical deterioration and no requirement for operative intervention.