The Retrograde Ulnar Dorsal Flap: Surgical Technique and Experience as Island Flap in Coverage of Hand Defects

Flaps from the forearm are often used to reconstruct soft-tissue defects in the hand. The retrograde ulnar dorsal flap has the advantage that it does not sacrifice a major vascular axis. The anatomic bases of this flap are the proximal and distal branch of the ulnar dorsal artery. The distal branch is partially accompanied with the dorsal branch of the ulnar nerve, and arrives under the abductor digiti quinti muscle making anastomoses with the deep branch of the ulnar artery. The proximal branch reaching the proximal third of the forearm, and anastomose with perforating branches of the ulnar artery. I used this island flap in 12 patients with coverage defects on the hand. The biggest flap was 13×6 cm. Only 1 flap had partial necrosis which did not lead to problems. The retrograde ulnar dorsal flap is a flap designed with reverse flow from the distal branch of the ulnar dorsal artery, and which does not sacrifice the ulnar artery. The donor defect on the forearm ulnar side had a greater esthetic acceptance. Knowing other distal anastomoses, described by other authors later, dorsal at the base of the fourth interdigital space grant greater security to the retrograde ulnar dorsal flap. It is worth highlighting the importance of preserving the adipofascial tissue around the pedicle. Experience with this flap permits us to state that it is a safe and reproducible flap to cover any defect on the dorsal of the hand as well as the first web space.