Sex Differences in Recovery of Brachial Plexus Injuries: Anatomical and Physiological Basis and Clinical Study
Abstract
Introduction: Brachial plexus injuries (BPIs) are severe, disabling, and impose a high socioeconomic burden. Restoring elbow flexion is paramount to functional recovery. Anatomical and physiological characteristics of peripheral nerves in males and the peripheral effects of testosterone may contribute to better recovery in men than in women. Materials and Methods: Observational, retrospective case series. Thirty-nine patients with BPI who underwent musculocutaneous nerve neurotization were included. Results: In males, the mean BMRC score was 4; the functional reinnervation rate (BMRC ≥3) was 89%, and the surgical failure rate (BMRC <3) was 11%. In females, the mean BMRC score was 3.5; functional reinnervation was achieved in 67%, with a surgical failure rate of 33%, and there was a greater tendency to failure with increasing patient age. Differences in strength achieved by subgroup according to the BMRC scale were statistically significant (p = 0.05). Conclusions: Men show a greater capacity for motor recovery than women after musculocutaneous nerve neurotization. Additionally, the risk of surgical failure increases with age in females. These findings may be explained by sex-related differences in peripheral nerve anatomy and physiology and by testosterone-related mechanisms acting on the nervous system and muscle.Downloads
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