[Effects of modified proper digital artery island flap in repairing complex fingertip defects]

Objective: To investigate the surgical method and clinical effects of the modified proper digital artery island flap in repairing complex fingertip defects. Methods: A retrospective observational study was conducted. From January 2017 to December 2021, 15 patients (15 fingers) with complex fingertip defects, involving the pulp, nail bed, and lateral wall of the nail, who met the inclusion criteria were admitted into General Hospital of Northern Theater Command, including 11 males and 4 females, aged from 18 to 55 years. The area of the post debridement wound was from 2.5 cm×2.0 cm to 3.5 cm×3.5 cm, and all the wounds were repaired by using modified proper digital artery island flap (including 3 parts: main flap, tongue-shaped flap, and triangular flap), of which the main flap was used to cover the finger pulp defect, the tongue-shaped flap was used to cover the nail bed and the nail lateral wall defect, and the triangular flap was inserted into the edge of the finger pulp wound to cover the vessel pedicle. The range of the flap ranged from 3.0 cm×2.0 cm to 4.5 cm×3.0 cm. The wound at the donor site was repaired with full-thickness skin graft of the groin, and the donor site of the skin graft was sutured directly. After operation, the survival of the flap and skin graft as well as and the appearance of the affected finger were observed. During the follow-up, the fingertip morphology of the affected finger was observed, two-point discrimination distance of the affected finger pulp was measured, and the patients' satisfaction with the efficacy (including very satisfied, satisfied, and dissatisfied) was asked, and the affected finger function was evaluated by the total active movement (TAM) system evaluation standard recommended by American Academy for Surgery of Hand. Results: After operation, the main flaps and skin grafts in 15 patients all survived; but the incision at the edge of tongue-shaped flap in one patient healed poorly, and one patient developed venous stasis at the distal end of the tongue-shaped flap; the triangular flap at the pedicle was slightly bloated in the early postoperative period and became smooth after 2 to 3 months. Overall, two patients developed subcutaneous hematoma in their flaps. All the complications were healed by appropriate dressing change, suture removal, or compression bandaging. After operation, the appearance of the flap was full and formed a prominent fingertip shape. During the follow-up of 6 months to 5 years, the fingertips of the affected fingers were prominent and full; the two-point discrimination distance of the affected finger pulp was (8.6±1.4) mm; 8 patients were very satisfied with the efficacy, 6 patients were satisfied, and one patient was dissatisfied; the functional assessment of the affected fingers were all excellent. Conclusions: The modified proper digital artery island flap can repair complex fingertip defects involving the pulp, nail bed, and lateral wall of the nail. The operation is simple, and the shape and function of the fingertip are good after surgery.