A Cadaver Study of the Feasibility of Multidigit Allotransplantation for Reconstruction of the Metacarpal Hand.

Abstract

Amputation of all fingers (metacarpal hand) can be functionally equivalent to hand amputation. Multidigit allotransplantation can benefit patients who require a full complement of fingers to return to their preinjury activities. The authors investigated the feasibility of the transfer of four fingers and thumb as a single allograft. Four fingers and the thumb were harvested from 16 hands as an allograft based on the radial and ulnar arteries. Dorsal digital veins were dissected until confluent in the major veins. The common digital nerves were divided at the origin. The flexor and extensor tendons were transected, respectively, in zones V and VI. The fingers were disarticulated at the metacarpophalangeal joint. After harvest, ulnar and radial arteries were injected with red and blue India ink, respectively, followed by injection of lead gel in the ulnar artery to study the perfusion of the fingers. Digital radiographs and computed tomographic scans were obtained. A bilateral mock transplantation was performed. The ulnar artery perfused the small, ring, long, and ulnar half of the index finger, whereas the radial artery vascularized the thumb. The index finger represented a watershed area. The presence of contrast in the four fingers, decreasing toward the radial fingers, was confirmed by computed tomography. The mock transplantation procedure was performed successfully. Multidigit transplantation is an anatomically feasible procedure. Although the ulnar artery can supply the entire allograft, the variable anatomy of the palmar arches should be considered and the flap based on both ulnar and radial arteries.