Collateral circulation in a patient with combined traumatic radial and ulnar artery injuries.

Combined radial and ulnar artery injuries are associated with a >35% amputation rate when not revascularized promptly. We describe a patient who suffered a penetrating injury to both the radial and ulnar arteries. Despite the ulnar artery being ligated and the radial artery primary repair becoming occluded after the index operation, his hand remained salvageable, likely because of collateral arterial pathways. The patient obtained a delayed radial-radial artery bypass and afterward achieved meaningful neuromotor function. This case emphasizes the importance of forearm vascular anatomy variability and the need for prompt management of arterial injuries to reduce limb loss and disability.