Anatomical study of Variations of Median Nerve and Musculocutaneous Nerve in the Arm

Abstract

Background: The variations related to the median nerve and musculocutaneous nerve are relatively less

common. The variations may have potential clinical implications especially during surgeries and nerve

blocks.

Materials and Method: The routine dissection of 50 adult cadavers including 42 males and 8 females in

the Department of Anatomy during undergraduate training was carried out to detect the variations in the

structure, formation and relation of Median nerve and musculocutaneous nerve.

Results and Findings: There was a variation observed in the formation of median nerve in three adult

cadavers. In three male cadaver, there was unilateral variation in the formation of the median nerve by more

than two roots . However, in each of these cadavers the distribution of the median nerve was normal in arm,

forearm and palm. There was normal pattern of formation, relation and course of Median nerve in rest of the

cadavers. Absence of musculocutaneous nerve, and nerve not piercing coracobrachialis, and communication

between median and musculocutaneous nerve was found. Photographs of abnormalities were taken for

proper documentation of the variations.

Conclusion: These variations have been explained by some embryological flats available. These variations

of formation of median nerve are clinically important for physicians, surgeons and anesthetists because

symptoms of median nerve compression due to these variations are often confused with radiculopathy

and carpal tunnel syndrome. The knowledge of variations of musculocutaneous nerve is important to the

surgeons and anesthetists’ for carrying out surgical procedures and nerve blocks in axilla and arm.