Distal Neurotization of the Anterior Interosseous Nerve to Recover Hand Grasping

Abstract

Lower trunk lesions are uncommon, representing about 3 to 5% of brachial plexus lesions in adults. One of the functions lost by patients who suffer this type of injury is the flexion of the fingers, with important harming of palmar grip. This series of cases proposes the transfer of a branch of the radial nerve to the anterior interosseous nerve (AIN), presenting a new alternative for the treatment of these lesions with highly satisfactory results. Objective: To demonstrate our strategy, technique, and results in the reinnervation of the AIN in lesions isolated from the lower trunk of the brachial plexus in four cases of high lesion of the median nerve. Method: Prospective cohort study in which four patients underwent neurotizations. The treatment was directed to the recovery of the fingers’ flexors of the hand and the grip. Results: All patients presented reinnervation of the flexor pollicis longus (FPL) and deep flexors of the 2nd, 3rd, and 4th fingers. The deep flexor of the 5th finger also showed reinnervation but with reduced strength (M3/4) comparing to the others (M4+). Conclusion: Despite the limited number of cases in this and other studies, the results are uniformly good, allowing to consider this treatment predictable. Level of Evidence IV, Case Series.