Use of a vascularized dorsal sensory branch of an ulnar nerve flap for repairing a proper digital nerve with coverage of a volar soft tissue defect: Report of two cases.

To repair a short nerve gap, autograft, allograft, autogenous, or synthetic conduits are selected, but a vascularized nerve autograft is preferred to obtain a reliable postoperative outcome in the case of an unfavorable wound bed. The purpose of this report is to describe and evaluate two cases of repair of a proper digital nerve and volar soft tissue defect with a vascularized dorsal sensory branch of an ulnar nerve flap. The cases of two men, 40 and 20 years old, who suffered index finger defects due to crush lacerations that required a flap and a nerve graft, are presented. A 4.0 cm × 2.0 cm and a 3.2 cm × 1.6 cm flap, which were nourished by the perforators from the ulnar proper digital artery of the little finger, were elevated from the ulnar side of fifth metacarpal bone head and transferred for coverage of the soft tissue defect. A 4.6-cm and a 3.0-cm vascularized nerve graft was interposed in the nerve gap. The patients' postoperative courses were uneventful, and both patients had no complaints related to the donor site. Static and moving two-point discrimination were 8 and 6 mm, respectively, at 6 months after surgery in the first case and 5 and 3 mm, respectively, at 9 months after surgery in the second case. This flap, which could be elevated in the same operative field with a nerve having similar diameter to that of the proper digital nerve, was useful for repair of a finger volar tissue defect.