Tortuous Ulnar Artery in the Distal Forearm.

Vascular anomalies of the upper extremity are rare and often challenging to diagnose. The ulnar artery, a terminal branch of the brachial artery, typically traverses the forearm and enters the hand through Guyon's canal, where vascular pathologies have been implicated in ulnar tunnel syndrome. However, vascular anomalies occurring outside Guyon's canal, such as a tortuous ulnar artery in the distal forearm, are seldom reported and remain poorly understood. We report the case of a 57-year-old male with a palpable mass on the volar/ulnar aspect of his distal forearm, which was associated with intermittent pain during hand use. Surgical exploration of the suspected mass revealed a tortuous ulnar artery without evidence of vascular malformations. To alleviate symptoms and reduce palpability, the artery was buried beneath the fascia. Postoperatively, the patient experienced complete symptom resolution with no recurrence of the mass or symptoms at three months postoperatively. This case represents the third reported instance of a palpable, tortuous ulnar artery as a distal forearm mass. This highlights a rare clinical entity that resulted in symptomatic resolution with both diagnostic and therapeutic surgical intervention. This also exemplifies the need for a broad differential diagnosis, a step-wise approach, and intimate knowledge of anatomy when treating masses of the forearm.