Thesubscapular arteryis the largest branch of the axillary artery. It distributes blood to the muscles of the scapular and shoulder regions. The subscapular artery branches off posteriorly into two stems, approximately four centimeters from its origin; its first branch is the circumflex scapular artery and its second is the thoracodorsal artery. The circumflex scapular artery supplies the clavicle and scapula, collectively known as the pectoral girdle, which help connect the upper limbs to the axial skeleton. The axial skeleton consists of the skull, vertebral column, and the thoracic cage. The thoracodorsal artery supplies the latissimus dorsi, the broadest muscle of the back.