Supercharged end-to-side anterior interosseous nerve transfer to the motor branch of ulnar nerve in high ulnar nerve injuries

Abstract

Ulnar nerve injury results in denervation of the intrinsic musculature of the hand which results in significant functional deficit, including weakness in grip power and key pinch. Despite the advances in microsurgical repair, the prognosis of a high level ulnar nerve injury is usually considered poor in terms of potential for motor recovery of the distal muscles of the hand. (1) Most of the series reported only 20% of M4 muscle power when the repair is performed in a position around the level of the elbow, irrespective of the use of grafts. (2-3) Due to these limited results obtained with the nerve repair, it has been recommended that distal tendon transfers should be offered as the first-choice surgical intervention for such cases, discouraging the nerve surgery. (4-5) However, tendon transfers in this situation are considered secondary salvage procedures and have been found to give only limited results. (6,7) With such a poor recovery potential, consideration can be given to a nerve transfer from the terminal branch of the anterior interosseous nerve to the deep motor branch of the ulnar nerve. This provides an expendable donor within close