Bilateral variation in origin of thoracodorsal artery along with non-piercing variant of musculocutaneous nerve on left side

Abstract

Subclavian artery continues as axillary artery in the axilla and is the principal source of blood supply of the lateral thoracic wall, axilla, scapular region, and upper limb. Thoracodorsal artery is one of the terminal branches of subscapular artery, which in turn is branch from the third part of axillary artery. Musculocutaneous nerve, a branch from lateral cord of brachial plexus, is the chief nerve supply of anterior compartment of arm, commonly seen piercing the coracobrachialis muscle before continuing as lateral cutaneous nerve of forearm. In the current case report, thoracodorsal arteries on both sides were arising from lateral thoracic artery, branch of second part of axillary artery and the left musculocutaneous nerve was not piercing the coracobrachialis muscles. Also, there was a communication between left musculocutaneous nerve and left median nerve. The knowledge about normal and variant pattern of origin and course of branches of axillary artery is very important as it may help the surgeons to identify the source of bleeding during surgeries in region of shoulder or axilla. Also, post-surgical complication or symptoms of nerve repair can be explained by the variation in course of musculocutaneous nerve and its communication with median nerve.