Comparing Flap Advancement and Wound Coverage of Anterograde Homodigital Neurovascular Island Flap Designs: A Cadaveric Model

Abstract

Anterograde homodigital neurovascular island flaps are a reconstructive option for volar fingertip injuries and confer the advantage of preserving fingertip sensation after surgery. However, the amount of flap advancement and wound coverage provided by stepwise and triangular flap designs remains unknown. This study sought to investigate how incremental proximal dissection of the pedicle influences flap advancement and whether advancement and/or coverage differ between the triangular and stepwise flap designs using 22 paired cadaveric digits. Flap advancement and wound coverage were evaluated in a pairwise design such that each pair of digits received 1 stepwise flap and 1 triangular flap. After creating a standardized injury to the volar fingertip, pedicled flaps were dissected from the middle phalanx and advanced distally under consistent tension. Advancement was measured for each 5 mm of proximal mobilization of the pedicle to a maximum of 30 mm. On average, 2.6 ± 0.2 mm of flap advancement could be achieved for every 10 mm of pedicle mobilization. With 30 mm of proximal mobilization of the pedicle, 11.8 ± 2.8 mm of advancement and 57.2% ± 16.1% of wound coverage could be expected. There were no significant differences between the flap designs. The stepwise and triangular anterograde homodigital neurovascular island flaps offer comparable and consistent reconstructive outcomes for volar fingertip injuries. The findings in this study suggest that the choice of flap design need not be influenced by the considerations of advancement or coverage; rather, surgeon preference or technical differences between the 2 flap designs may be of more importance.