Computed tomography of traumatic abdominal wall hernias: recognition, associated injuries, and impact on management...

Traumatic abdominal wall hernias are seen following abdominal trauma, in the setting of blunt injuries. Due to the nature of presentation, their assessment and treatment is frequently deferred until threats to life are managed surgically and the patient has made a sustained postoperative recovery, often extending beyond the period of rehabilitation. There can be an underappreciation of the substantial force required to create a hernia, which occur following blunt trauma secondary to shearing forces and sudden increase in intra-abdominal pressure. Traumatic abdominal wall hernias are a rare occurrence, most commonly occurring in the inferior lumbar triangle, typically following a road traffic collision. Prompt identification of traumatic abdominal wall hernias is critical as these injuries are commonly associated with severe internal injuries and complications. One of the most commonly associated injuries is to the mesentery/bowel. Other acute injuries associated with traumatic abdominal wall hernias include axial skeleton fractures, vascular injury, and solid organ injury including pancreatic injuries. Thus, identifying traumatic abdominal wall hernias on initial trauma imaging is essential to guide surgical management and the need for repeat imaging in the acute setting. Computed tomography (CT) is a highly sensitive imaging modality for detecting traumatic abdominal wall hernias and their associated acute complications and is the mainstay of acute imaging assessment. This pictorial review will describe the normal anatomy of the abdominal wall on CT; illustrate findings of traumatic abdominal wall hernias along with important concomitant, but potentially subtle, injuries on a number of complex polytrauma patients; and demonstrate the role of CT in the later definitive management of traumatic abdominal wall hernias.