Axillary Artery Injury in Proximal Humeral Fractures: Displacement Medial to the Coracoid on X-ray as a Risk Sign of Vascular Injury

Axillary artery injury is a rare but serious complication of proximal humeral fractures that can threaten both life and limb. The artery lies in close proximity to the glenoid and humerus, making it susceptible to laceration, thrombosis, or pseudoaneurysm during trauma or surgical fixation. Medial translation of the humeral shaft under the coracoid on a radiograph may help surgeons predict arterial injury and prepare accordingly. A retrospective review of cases in a large UK shoulder unit covering a million patients identified five cases over the last three years where proximal humeral fractures were complicated by vascular injury during surgery. The arterial injuries ranged from axillary artery tears with catastrophic bleeding, branch lacerations, and the formation of pseudoaneurysms. Treatment required vascular surgical repair of tears, bypass grafting, and embolization through interventional radiology for a pseudoaneurysm. While there was no loss of life, brachial plexus injury occurred in the catastrophic bleed cases. Avoiding vessel tearing may have been achieved by first approaching the artery in cases where the humeral shaft lies beneath the coracoid. Early computed tomography angiography with a coordinated orthopedic-vascular multidisciplinary approach may facilitate preoperative recognition and management of this uncommon injury.