Outcomes after Anterior Interosseous Nerve to Ulnar Motor Nerve Transfer

Abstract

Background Ulnar nerve lesions proximal to the elbow can result in loss of intrinsic muscle function of the hand. The anterior interosseous nerve (AIN) to deep motor branch of the ulnar nerve (DBUN) transfer has been demonstrated to provide intrinsic muscle reinnervation, thereby preventing clawing and improving pinch and grip strength. The purpose of this study was to evaluate the efficacy of the AIN to DBUN transfer in restoring intrinsic muscle function for patients with traumatic ulnar nerve lesions. Methods We performed a prospective, multi-institutional study of outcomes following AIN to DBUN transfer for high ulnar nerve injuries. Twelve patients were identified, nine of which were enrolled in the study. The mean time from injury to surgery was 15 weeks. Results At final follow-up (mean postoperative follow-up 18 months + 15.5), clawing was observed in all nine patients with metacarpophalangeal joint hyperextension of the ring finger averaging 8.9 degrees (+ 10.8) and small finger averaging 14.6 degrees (+ 12.5). Grip strength of the affected hand was 27% of the unaffected extremity. Pinch strength of the affected hand was 29% of the unaffected extremity. None of our patients experienced claw prevention after either end-to-end (n = 4) or end-to-side (n = 5) AIN to DBUN transfer. Conclusion We conclude that, in traumatic high ulnar nerve injuries, the AIN to DBUN transfer does not provide adequate intrinsic muscle reinnervation to prevent clawing and normalize grip and pinch strength.

Reconstructing Pinch Strength after Ulnar Nerve Injury by Transferring the Opponens Pollicis Motor Branch

“…Both values are greater than the 27% and 29% for grasp and terminal key pinch obtained after distal anterior interosseous nerve transfers to the deep terminal division of the ulnar nerve at the wrist. 19 It is possible that reconstruction of the muscles of the first web space by Opp transfer contributed to the improvement in grasping and key pinch strength our patients experienced. However, because of dependence on thumb and finger flexors, grasping and key pinch improvement could result from natural adaptation, or from the ulnar nerve repair performed in our patients.…”

Updates in peripheral nerve surgery of the upper extremity: diagnosis and treatment options

“…Despite encouraging results on the MRC grading scale, however, nerve transfers for proximal ulnar nerve lesions are not effective in preventing clawing and do not come close to normalizing grip and pinch strength when compared to the contralateral unaffected limb ( 79 ).…”

A Systematic Review of Registered Clinical Trials for Peripheral Nerve Injuries

“…Although existing studies have explored a range of management strategies for PNI, including surgical techniques (such as end-to-end repair, end-to-side repair, reverse end-to-side repair, nerve grafting, and nerve transfers) 4–7 and nonsurgical interventions like targeted physical therapy and medication, 8–11 there remains a significant gap in our comprehensive understanding of optimal treatments for upper extremity PNIs. This gap is exacerbated by various research challenges, such as difficulties with retrospective data collection, reporting biases, inconsistent application of outcome measures, and suboptimal data sharing practices.…”