Neurovascular pulp island flaps from the lateral half of the large toe provide glabrous skin similar to that of the fingertips. They are ideally suited for resurfacing the tactile pad of the thumb or fingers and small critical weight-bearing areas on the soles of the feet. The donor defect on the toe can usually be closed primarily if flaps of I and 1.5 cm or less are needed. Larger flaps require a skin graft on the toe, which considerably prolongs the recovery.

Flaps can extend from the nail margin to the midline and must be mobilized on the lateral digital neurovascular pedicle. The plantar digital nerve supplying this island has the potential to provide two-point discrimination of 3 to 4 mm in young people, making it the best free sensory island flap available. Insensate skin surrounding this small island at the recipient site becomes neurotized by the flap so that protective sensation can be expanded to an area two to three times the size of the island. This effect becomes important when the island is used as a pressure sensor in areas around the weight-bearing surfaces of the sole of the foot. When used in this manner, the island can be transplanted on an intact vascular pedicle, mobilizing the nerve proximally by splitting it from the common digital nerve. The digital artery to the medial aspect of the second toe must be ligated and divided if only the lateral skin of the great toe is to be used. This maneuver creates a pedicle long enough to allow transfer of the flap to the weight-bearing area over the heel. A large flap can be fabricated by carrying the medial side of the second toe and the first web space on this common vascular pedicle. Occasionally, with a dominant dorsal circulation, it is possible to use the first dorsal metatarsal artery to perfuse the web space flap. In this situation, the deep peroneal nerve can also be used to provide sensation to the skin on the dorsum of the web space; however, the dissection must also include the plantar nerves because they provide sensation to much of the skin on the lateral aspect of the toes.

Clinical Cases

CASE 1

This case illustrates surgery performed on April 22, 1974. (From Buncke, H.J.: Free toe-to-hand transplantation by microvascular anastomosis. Transactions of 6th International Symposium of Plastic and Reconstructive Surgery, Masson, Paris 1975.)

FIG. 2-01. The distal phalanx and pulp of the right thumb have been resurfaced with an abdominal tube after an avulsive injury. The pad was insensate, floppy, and subject to constant trauma.

FIG. 2-02. A neurovascular island flap was planned from the lateral aspect of the large toe, carrying the digital artery and nerve and a dorsal vein.

FIG. 2-03. The large island flap from half of the toe is completely isolated on the neurovascular pedicle,

FIG. 2-04. The thumb is amputated when the recipient area is ready.

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