Exploring Variations in Median Nerve Formation: Embryological Basis and a Pathway to Improved Clinical Outcomes

Aim This study investigated the gross anatomical variability in the formation of the median nerve and evaluated its clinical and surgical implications. The research aimed to observe variations in median nerve root formation, compare differences between sides and genders, and to understand the embryological basis of these variations. Materials and methods A cadaveric investigation was conducted on 60 upper limbs (ULs) from 30 embalmed adult cadavers (15 males and 15 females). An infraclavicular approach was used for dissection, following standard dissection protocols. The number of roots forming the median nerve, along with their relationship to the axillary artery, was documented and analysed. Statistical analysis included chi-square and Fisher's exact tests to correlate findings with age, gender, and laterality. A p-value of less than 0.05 was considered statistically significant. Results Significant variations in median nerve formation were observed in 21 (35%) of specimens. The classic two‑root pattern was present in 39 (65%) of limbs. Three‑root contributions occurred in 17 (28.33%) of cases, predominantly in males. Four‑root contributions were identified in three (5%) of specimens, while single‑root formation was observed in one (1.67%). Only one (1.67%) specimen demonstrated an absent musculocutaneous nerve, with compensatory median nerve innervation to the anterior arm muscles. Gender showed a statistically significant association with root variations, with males exhibiting a higher incidence of contributions from multiple roots. Conclusion Variations in median nerve formation are relatively common and clinically significant. The diversity of morphological patterns necessitates heightened awareness among surgeons, anaesthesiologists, and neurologists. Understanding these anatomical variations is essential for preventing iatrogenic injuries during surgical procedures, ensuring successful regional anaesthesia, and for accurately interpreting atypical neurological presentations.