Double Nerve Transfer Versus Triple Nerve Transfer for Elbow Flexion Restoration in C5-C6 Traumatic Brachial Plexus Injuries.

Objectives: This preliminary study compares two nerve transfer techniques for restoring elbow function in patients with C5-C6 brachial plexus injuries. The double nerve transfer (Oberlin II) involves the transfer of fascicles from the ulnar and median nerves to the biceps and brachialis muscles. In contrast, the triple nerve transfer (Oberlin III) includes an additional transfer from the radial nerve to the brachioradialis muscle. Methods: Nine patients with C5-C6 traumatic brachial plexus injuries were included in the study and followed for five years after nerve transfer surgery. Four patients underwent the Oberlin III technique, while five received the Oberlin II procedure. Outcomes assessed included the range of motion in the elbow and shoulder joints, hand grip strength, elbow flexion strength, elbow flexion velocity, and brachioradialis muscle bulk. Results: All patients achieved an MRC grade of 4 for elbow flexion strength. Brachioradialis muscle bulk was recovered in the Oberlin III group, which also demonstrated a higher elbow flexion velocity (P = 0.032). Additionally, higher mean values were observed in the Oberlin III group for elbow flexion strength (in both supination and pronation) and QuickDASH scores. However, no statistically significant differences were found for these outcomes. Conclusion: The Oberlin III technique was associated with the recovery of brachioradialis muscle bulk and improved elbow flexion velocity. These preliminary findings suggest potential functional benefits, highlighting the need for further investigation in larger cohorts.