Retrograde-flow neurocutaneous island flaps in the forearm: anatomic basis and clinical results.

The neurocutaneous island flap is an axial flap whose arterial vascularization is provided by the vascular plexus around and inside the cutaneous nerve. In previous studies we successfully harvested neurocutaneous island flaps in the hand and in the forearm. Here we report on reverse-flow neurocutaneous island flaps for reconstructions in the distal third of the forearm. The vascularization of the cutaneous nerve of the forearm was studied in 15 fresh human upper limbs injected with polyester resin. The vascularization of the cutaneous nerve was found to be very closely connected with the vascularization of the skin. A vascular arcade followed the cutaneous nerve of the forearm. These paraneural vessels linked the neurocutaneous perforators and together with the cutaneous nerve overlay a major vascular axis. A close relationship between the cutaneous nerve and the neurocutaneous perforators was clearly identified. The cutaneous nerve crossed in every instance the point at which the neurocutaneous perforators reached the skin. Anastomosis between the paraneural vessels and the intraneural circulation was consistently found. On the basis of these anatomic findings, reverse-flow neurocutaneous island flaps were raised on the forearm of three patients and are reported on.