Blunt Innominate Artery Injury

Traumatic injury to the innominate artery is a rare occurrence. A literature review reveals that penetrating wounds account for the overwhelming majority of these injuries. Fewer than 90 cases of innominate artery injury caused by blunt trauma have been documented. Over the past 12 months the trauma service successfully treated two patients with blunt injury to the innominate artery. Both cases involved high-speed motor vehicle crashes with sudden deceleration. Both patients were wearing lap and shoulder restraints and had similar associated bruising following the line of the shoulder harness. The first patient presented with a wide mediastinum on chest X-ray. Angiography revealed an innominate artery injury at the aortic arch. The second patient had a normal chest X-ray. Given the extent of soft tissue bruising from the shoulder harness he underwent a magnetic resonance angiography, which was suspicious for an innominate artery injury. Arch aortography confirmed a disruption of the innominate artery midway between its origin and its bifurcation. Both were repaired through a median sternotomy with cervical extension as necessary. Given the present technology of safety restraint devices this injury may occur with greater frequency. A “shoulder strap sign” should prompt a search for more extensive injuries.