Repair of digital volar complex soft tissue defect with heterodigital antegrade digital artery island flap innervated by digital nerve

Abstract

To investigate the effectiveness of heterodigital antegrade digital artery island flap innervated by proper digital nerve and the dorsal branch of proper digital nerve for repairing digital volar complex soft tissue defects. Between May 2014 and January 2018, 27 patients with digital volar complex soft tissue defects were treated. There were 17 males and 10 females with an average age of 37 years (range, 18-60 years). The causes included electric saw injury in 8 cases, twisted injury in 12 cases, and heavy pound injury in 7 case. There were 9 thumbs, 5 index fingers, 6 middle fingers, 3 ring fingers, and 4 little fingers. The interval between injury and admission ranged from 1 to 4 hours (mean, 2.5 hours). The defect size ranged from 2.2 cm×1.4 cm to 3.8 cm×2.3 cm. The mean length of unilateral proper digital nerve defect was 2.9 cm (range, 2-4 cm). All defects were repaired with heterodigital antegrade digital artery island flap innervated by the proper digital nerve and the dorsal branch of the proper digital nerve. The proper digital nerve and the dorsal branch of the proper digital nerve in the flap were anastomosed with the proper digital nerve stumps in the wound. The flap size ranged from 2.4 cm×1.6 cm to 4.1 cm×2.6 cm. A segment of dorsal branch of the proper digital nerve was intercalated into the defect of the proper digital nerve in donor site. And the defect of donor site was repaired with the full-thickness skin graft. All flaps and skin grafts survived, and the wounds healed by first intention. All patients were followed up 12-24 months (mean, 17 months). The appearance, color, and texture of the flaps were similar to the surrounding tissue. There was no pain and double sensibility in any flap. At last follow-up, the static two-point discrimination of the flaps ranged from 4 to 8 mm (mean, 5.3 mm). And the two-point discrimination of digital pulps of recipient and donor fingers ranged from 4 to 10 mm with the average of 6.2 mm and 6.0 mm, respectively. According to the functional assessment criteria of the upper limb formulated by the Hand Surgery Society of the Chinese Medical Association, the results were excellent in 18 cases and good in 9 cases. No scar contracture was observed in donor site. The heterodigital antegrade digital artery island flap innervated by the proper digital nerve and the dorsal branch of the proper digital nerve provides a safe and simple technique with minimal donor site cost and satisfactory effectiveness, which could be an ideal option for repairing digital volar defect, especially for the defect complicated with digital nerve defect.