Direct End-to-End Neurorrhaphy for Wrist-Level Long Nerve Defect with Fixation of the Wrist in Flexion: Technique Note

Background For a nerve gap, end-to-end neurorrhaphy would either be difficult or would include tension. The use of a nerve graft or conduit could be a solution, but it might compromise the reinnervation. We describe a method for wrist-level ulnar and/or median long nerve injury by fixing the wrist in the flexion position with K-wire (s) to make possible an end-to-end and tension-free neurorrhaphy. Patients and Methods Two patients had wrist-level ulnar nerve injury for 2 and 3 months and nerve gaps of 2.5 cm and 3.5 cm, respectively, after the neuroma excision. K-wires were used to transfix from the radius to carpal bones, in order to keep their wrists in flexion of 45 and 65 degrees, respectively, with which the tension-free end-to-end neurorrhaphy could be achieved. The K-wires were removed in 6 weeks after surgery, and their wrists were kept in the splint for a progressive extension program. Results Both patients were noted to have an improved claw hand deformity 4 months after the surgery. The ulnar nerve motor and sensory function could be recovered mostly in the 12-month follow-up. The wrist flexion and extension motion arc both achieved, at least, 150 degree in the 12-month follow-up. There were no complications related to the K-wire fixation. Conclusion With the wrist fixed in a flexed position, maintaining a longer nerve gap to achieve a direct end-to-end and tension-free neurorrhaphy would be more likely and safer. Without the use of nerve graft, innervation of the injured nerve would be faster.