Abstract： Objective:To investigate the clinical efficacy of dorsal thumb neurocutaneous vascular flap pedicled with digital arterial dorsal branch for the repair of the soft tissue defect of ulnar thumb.Methods:From July 2015 to May 2023, our department used dorsal thumb neurocutaneous vascular flap pedicled with digital arterial dorsal branch to repair the soft tissue defect of thumb, and applied microsurgical techniques to expose, separate, and rotate the pedicle. There were 29 patients in this group, 19 males and 10 females. The age range was 21 to 57 years old, with an average of 32.6 years old. There were 13 cases of machine strangulation injury, 10 cases of crushing injury, 4 cases of chainsaw injury, and 2 cases of cutting injury. There were 9 cases on the left and 20 cases on the right. The flap was cut from a range of 1.0 cm×1.5 cm to 1.5 cm×3.0 cm, and the donor site wound was directly pulled and sutured.Results:All 29 skin flaps survived after surgery, and the wounds achieved primary healing. The postoperative follow-up was 11 to 21 months, with an average of 17.5 months. The last follow-up showed satisfactory appearance and texture of the skin flap, and good recovery of finger function. The patient was satisfied with the postoperative efficacy.Conclusion:The nutrient vessel pedicle of the radial nerve superficial branch of the intrinsic artery perforating branch of the finger flap is constant, carrying nerves that can reconstruct the sensation of the thumb, making it easy to cut. The application of microsurgical techniques makes the blood supply of the flap more reliable, the damage to the donor area is small, the postoperative recovery is fast, the hospital stay is reduced, the repair and treatment of the thumb ulnar defect wound is satisfactory, and it is convenient for clinical promotion.