gms | German Medical Science

Objectives/Interrogation: The vascularized half-big toenail flap was originally developed by Kuroshima in 1990. This flap is a short-pedicled free vascularized flap of approximately 30 mm in size that contains a fibular half nail with a 5 mm skin edge and partial distal phalanx bone. The fingertip skin of the amputated finger is reflected to cover the skin deficiency. The sensation and function of the donor site are maintained, and primary wound closure of the donor site is possible. We herein report cases of thumb and finger reconstruction using this flap.

Methods: We assessed 16 patients (11 cases of single-digit amputation, 5 cases [8 digits] of multiple-digit amputation) who underwent this procedure among 108 (85 cases of single-digit amputation; 23 cases [47 digits] of multiple-digit amputation) who were indicated for reconstructive surgery between 2007 and 2017. We evaluated the following parameters: digits, amputated level, survival rate, elongated length, feeding artery, vein distribution, width and length of nails, longitudinal and axial convexity of nails before surgery/final follow-up and complications. We used the Mann-Whitney U test to evaluate the significance of differences.

Results and Conclusions: The reconstructed digits were three thumbs, five index fingers, five middle fingers and six ring fingers. The amputated levels were Tamai Zone II to IV. The flap survival was obtained in all cases, including one atrophic case. The elongated length was 14.1 mm (range, 0 to 30), including 4 cases of iliac bone graft. The feeding artery to the flap was the digital artery in 15 toes, anonymous artery in 3, and a branch of the digital artery in 1. We harvested the vein in the first web in 16 toes. The mean width and length and the longitudinal/axial convexity of the transferred nail before surgery and final follow-up were as follows: 8.0 to 9.2 mm (p<0.01), 14.2 to 11.7 mm (p<0.01), 10.8° to 23.1° (p<0.05) and 32.9° to 61.1° (p<0.01), respectively. Complications were partial necrosis of the skin graft and delayed wound healing of the donor site. Multiple-digit defects were more unacceptable to our patients than a single-digit defect, and they preferred cosmetic improvement to functional improvement. This flap restored the thumb's availablity to grasp and made the middle finger longer than other fingers with no functional deficits at the donor site. Morphological adjustment of the transferred nail at surgery was unnecessary, as the donor site nail ultimately resembles the finger nail.