Variations in the Branching Pattern and Course of the Left Axillary Artery: A Cadaveric Case Report

The axillary artery is the primary arterial supply of the upper limb and functions as a key landmark in the region of the axilla. Anatomical variations in the axillary artery may arise from abnormal angiogenesis in the upper limb bud during embryological development. The routine dissection of the upper limb of an 88-year-old male cadaver revealed unilateral variations in the left axillary artery, including an abnormal anteromedial course with respect to the divisions and cords of the brachial plexus, while no variations were observed in the right axillary artery. Variations in branching were observed in each part of the artery. In the first part of the artery, variations included an accessory branch coursing towards the clavicle and another to the subscapularis muscle. A total of four branches arose from the second part of the artery: a thoracoacromial artery, an accessory pectoral branch, and two common trunks. The first common trunk gave off the alar thoracic artery, an accessory lateral thoracic artery, and the subscapular artery, which further gave off the thoracodorsal and lateral thoracic arteries, prior to continuing as the circumflex scapular artery. The second common trunk yielded the anterior and posterior circumflex humeral arteries prior to continuing as the profunda brachii artery. No branches arose from the third part of the artery. Awareness of variations in the course and branching patterns of the axillary artery as observed in this cadaveric donor is essential for anesthetic, radiographic, surgical, and other interventional procedures of the upper limb.