Comparative Study of Elbow-Flexion Gain in Patients with Upper Brachial Plexus Injury Using the Oberlin Neurotization Technique versus Free Gracilis Muscle Transplantation Neurotized with an Ulnar Nerve Fascicle.

INTRODUCTION: There is a consensus in the literature regarding the excellent outcomes achieved with the Oberlin procedure for the treatment of upper brachial plexus injuries (C5-C6 and/or C7) in restoring elbow flexion. However, some limitations exist when this procedure is performed long after the initial trauma. An alternative is the free gracilis muscle transfer, using a fascicle of the ulnar nerve as the donor nerve. The aim of this study was to compare the Oberlin procedure and free functional gracilis muscle transfer in terms of elbow flexion strength recovery. METHODS: A non-randomized retrospective cohort study was conducted comparing these two techniques in 69 patients with upper brachial plexus injuries, evaluating postoperative elbow flexion strength. The minimum follow-up period was 12 months. RESULTS: With regard to elbow flexion recovery, there was no statistically significant difference in the proportion of good results (M4 strength) between the two groups (60.4% for the Oberlin group and 61.9% for the free gracilis group). When subdividing the Oberlin group according to the maximum time interval between injury and surgery (≤6, ≤9, and ≤12 months), the rates of good results (M4) were 65.2%, 60.4%, and 58.3%, respectively. No statistically significant differences were found either among these subgroups or between any of them and the free muscle transfer group. CONCLUSION: The Oberlin procedure provides elbow flexion strength comparable to that achieved with free functional muscle transfer when performed within 12 months after the initial brachial plexus injury.