Images in vascular medicine Hypothenar hammer syndrome

A 31-year-old carpenter was evaluated for the recent onset of coolness and pallor of the right fourth finger. He has used the palm of his right hand to drive tacks for many years. His family and past medical history was unremarkable. He took no medication. On physical examination, he had normal brachial, radial, and ulnar pulses in both arms. Allen’s test with right radial artery compression revealed mild slowness of capillary refill in the fourth and fifth fingers. Angiography of the right hand revealed a tortuous, redundant, and ectatic ulnar artery forming a small aneurysm (open arrows on Panels A and B), with abrupt occlusion of its distal distribution over the fourth and fifth digits and intraluminal filling defects (solid arrows in Panel A) consistent with an embolic process. This condition, hypothenar hammer syndrome, is caused by repetitive blunt trauma to the hypothenar eminence and consequently to a vulnerable portion of the ulnar artery over the