Unilateral Absence and Contralateral Communication Between Musculocutaneous and Median Nerve and Its Clinical Significance

Variations and Communications between the branches of different cords is not uncommon. Martin Gruber anastomosis, Berretini anastomosis and Cannieu and Riché anastomosis are few examples of such nerve communications. During routine anatomy dissection of axilla, in a 65 years old female cadaver, we found absence of musculocutaneous nerve in left upper limb. It was found that all the muscles of front of arm were supplied by median nerve on this side. When compared on the right side, there was one communication between musculocutaneous nerve and median nerve. This communicating branch was 75 mm long. All the muscles of anterior compartment of arm were supplied by MCN and the nerve continued afterwards as lateral cutaneous nerve of arm. The knowledge of such variations helps us in neurosurgeries like surgery for Neurofibromatosis. Orthopedic, general surgeons and neurosurgeons must consider the possibility of such variations in the surgery of arm and elbow. Surgeons who perform neurotization procedures of the musculocutaneous nerve to restore elbow flexion should be aware of these anatomical variations Cutting of such communicating branch can lead to altered mobility of limb.