Nerve Transfer for Triceps Reinnervation in Obstetrical Brachial Plexus Injury: Long-Term Functional Results

Restoration of elbow extension in obstetric brachial plexus injury (OBPI) with triceps paralysis is essential for optimizing upper limb function, although often considered a secondary objective.

To assess long-term functional outcomes of triceps reinnervation via nerve transfers in pediatric OBPI patients with persistent triceps paralysis.

This retrospective cohort included 16 patients who underwent triceps reanimation between 2007 and 2018. Inclusion criteria were the absence of active elbow extension and a minimum 4-year follow-up. Depending on the lesion level, nerve transfers involved motor branches of the ulnar nerve to the flexor carpi ulnaris (FCUm) and intercostal nerves. Descriptive notes of these procedures are provided in the text. Outcomes were evaluated using the Medical Research Council (MRC) scale for strength and Gilbert's Elbow Scale (GES) for function.

Mean age at surgery was 48.9 months (range: 8-96), with a minimum follow-up of 4 years. At final evaluation, triceps strength improved significantly (mean MRC: 3.75, median: 4) as did elbow function (mean: GES 3.75, median: 4) compared with preoperative values ( p  < 0.01). Triceps recovery contributed to a mean 35-degree reduction in elbow flexion contracture, suggesting a preventive role against progressive deformity. No complications or donor site morbidity were observed.

Delayed nerve transfers for triceps reinnervation-performed up to 8 years of age-yielded satisfactory long-term results without compromising recovery. These findings support including elbow extension restoration among surgical priorities in OBPI management, even for complete brachial plexus palsies when suitable donor nerves remain available after primary reconstructions.