VARIATION IN FORMATION OF MEDIAN NERVE AND PROFUNDA BRACHI ARTERY

INTRODUCTION: Median nerve is formed in axilla by the union of medial root of median nerve and lateral root of median nerve. The medial root crosses downward and laterally in front of the third part of axillary artery and joins with lateral root. Profunda brachii artery  is a large branch arising from the posterior surface of the proximal part of the brachial artery and follow the radial nerve to enter the spiral groove. AIM AND OBJECTIVE: To study the variation in formation of median nerve and anatomical variations in arterial  formations – profunda brachii artery because knowledge of such variations is important in clinical practice for evaluation of injuries without misinterpretation of clinical symptoms and during surgeries of limbs to prevent accidental injuries to nerves and vessels . MATERIAL AND METHODS: This study was conducted in Department of Anatomy of Osmania medical college ,koti, Hyderabad. During routine undergraduate dissection on 22 formalin fixed human  cadaver  20 males & 2 female (44 upper limbs); were dissected for the study. The cadavers with visible trauma, pathology or prior surgeries were excluded from the study. Routine dissection of the axilla and upper limb was followed. After removal of skin, loose connective tissue, fat and lymph nodes of axilla the cords of  brachial plexus were identified and the median nerve was identified & carefully dissected, and also axillary artery and brachial artery identified and dissected. At first, the origin is confirmed and then they were  traced  down . Any variations found were noted and photographed. The results were analysed and compared to previous studies. RESULTS: Low level of formation of median nerve in arm , profunda brachii artery arising from third part of axillary artery and its passage between medial root of median nerve and lateral root of mediannerve was identified in one cadaver on right side.The percentage of low level formation of median nerve in arm and passage of profunda brachii artery in between medial root of median nerve and lateral root of median nerve is 2% among 44 upper limbs. CONCLUSION: The knowledge on median nerve variations and upper extremity vasculature variations is essential for medical practitioners, anatomists, radiologists, anaesthetist, neurosurgeons and orthopaedic surgeons during surgical operation of the upper limb and is essential to prevent injury and post operative complications particularly in patients requiring  dialysis or undergoing arteriography. Also, it is also important for those patients who need arteriovenous bypass .