Traumatic ulnar artery aneurysm and the hypothenar hammer syndrome

Ulnar artery aneurysms are uncommon and have been linked with traumatic injuries to the hand. These aneurysms are most commonly seen in workers who use the hypothenar eminence of their hands as a hammer and can be accompanied by a constellation of symptoms. Both penetrating and blunt trauma have been documented as sources of ulnar artery aneurysms and its subsequent sequela. In this case report, we describe a 45-year-old gentleman who presented with digital ischemia of his 4^th and 5^th digits and other clinical symptoms of the hypothenar hammer syndrome after performing manual labor. His initial management, method of diagnosis, operative intervention, and perioperative management are discussed. Ulnar artery aneurysms, while uncommon, can lead to a limb-threatening event. A high index of suspicion for ulnar artery aneurysms must be considered in patients with an antecedent history of acute or repetitive trauma. While there are multiple diagnostic modalities and minimally invasive alternatives to treatment, operative exploration is the definitive method of diagnosing and treating ulnar artery aneurysms.