Abstract: Hand Transplantation in Patients with Extensive Burns of the Upper Extremities: Anatomical Study on Feasibility

Abstract

INTRODUCTION: Hand transplantation in patients with severe burns of the upper extremity presents unique challenges because of extensive skin and soft tissue deficit. In skin grafted recipient limbs there is an increased risk of exposure of vascular anastomosis, tendons and nerves. The aim of this anatomical study was to evaluate how to reliably transfer increased amounts of skin from the upper extremity based on the perforators of the main axial vessels to replace the scarred recipient skin. METHODS: 25 upper limbs were studied. Based on the vascular anatomy of the perforators, forearm based hand allografts were harvested with 3 different patterns: A) volar and dorsal forearm flaps based only on distal perforators of Radial (RA), Ulnar (UA) and Posterior Interosseous (PIA) arteries and islanded medial arm flap based on Brachial and/or Superior Ulnar Collateral (SUCA) arteries; B) volar and dorsal forearm flaps with preservation of proximal RA perforators with only distal UA perforators and the islanded medial arm flap C) dorsal forearm flap and extended medial arm-volar forearm skin flap. 16 samples were injected with latex to map the perforating branches of the BA, SUCA, RA, UA and PIA. 3 samples for each group were dissected and injected with blue ink from the proximal BA to assess the retained perfusion of the flaps. RESULTS: The medial arm flap was constantly supplied by perforators from the BA and the SUCA (respectively 4.35 ± 1.64, diameter 1.03 ± 0.34mm and 2.6 ± 0.76, diameter 0.90 ± 0.34mm) and adequately perfused when the perforators from the BA or SUCA were preserved (90.8% stained). Perforators from RA (9.3 ± 1.62) if preserved, proved to be adequate to supply the total volar forearm skin (87.6% stained). The harvesting of the PIA with its perforators (5.25 ± 0.95) provided vascularization to the proximal half of the posterior flap. CONCLUSION: The medial arm flap should be safely based on perforators from the BA and/or SUCA. The design of the specimens in group B proved higher vascularization reliability and versatility as they provided adequate vascularization to the skin flaps with minimal interference with the dissection and repair of vessels, tendons and nerves.