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

Area of Science:

• Orthopedic Surgery
• Neurosurgery
• Hand Surgery

Background:

• Ulnar nerve injuries commonly cause paralysis of intrinsic hand muscles, leading to weakened pinch.
• The first dorsal interosseous and adductor pollicis muscles are crucial for effective pinch function.

Purpose of the Study:

• To evaluate the efficacy of transferring the opponens pollicis motor branch to the deep terminal division of the ulnar nerve for pinch reconstruction.
• To assess the impact of this nerve transfer on pinch and grasp strength.

Main Methods:

• A cohort of 16 patients with ulnar nerve injuries underwent opponens pollicis motor branch transfer.
• Patients were followed for a minimum of 14 months postoperatively.
• Preoperative and postoperative pinch and grasp strengths were measured using dynamometry.

Main Results:

• Reinnervation of the first dorsal interosseous muscle occurred in 15 of 16 patients.
• Mean grasp strength improved significantly postoperatively (57% of contralateral side).
• Subterminal key pinch strength improved to 61% of the unaffected side, with better outcomes for earlier surgical intervention.

Conclusions:

• Transferring the opponens pollicis motor branch is an effective technique for restoring pinch and grasp strength after ulnar nerve injury.
• This surgical approach improves hand function without compromising thumb function.