Correlation between intelligence, level of formal education, and nerve transfers for elbow flexion recovery outcomes following brachial plexus reconstructive surgery

Abstract

Background: Several factors have been shown to influence post-surgical recovery for elbow flexion repair after nerve transfers for brachial plexus surgery. The brain´s impact on surgical outcomes has garnered considerable attention, prompting an investigation into the influence of various cortical functions, including intelligence and academic achievement. The aim of this study is to investigate whether intelligence is correlated with functional outcomes of elbow flexion following nerve transfer.Methods: We conducted a retrospective study of patients who underwent nerve transfers to restore elbow flexion. Intelligence was assessed using the WAT BA and Matrix Reasoning subtest (MRT) of the WAIS-III, and the grade of scholarship was evaluated based on the years and levels of education completed. Motor recovery was assessed through the British Medical Research Council (BRMC) scale and strength index scores.Results: A total of 71 patients were included, with a mean Intelligence score of 89 (range 67-114). Intelligence correlated with BRMC motor outcomes (p = 0.023, r = 0.270). Additionally, patients with lower intelligence scores (<85) experienced a prolonged time from trauma to surgery (p = 0.017) and lower rehabilitation quality scores (p = 0.001, CC = 0.398). Notably, patients with ≤7 years of education and lower scholarship levels demonstrated significantly lower BRMC scores (p = 0.049).Conclusion: A positive association was found between higher Intelligence, and motor recovery following nerve transfer surgery. This relationship may be attributed to direct differences in cortical abilities and to indirect factors, such as delayed surgery and suboptimal adherence to rehabilitation.