The subscapular artery is the artery of the posterior wall of the axilla and follows the lower border of the subscapularis to the medial wall. It then sends a large branch, the circumflex scapular artery, to the dorsum of the scapula by way of the triangular space. Its other branches (five in number) accompany important motor nerves, ie, the first assuming the posterior humeral circumflex artery to spring from its root, which it commonly does, and passes through the quadrangular space with the circumflex (axillary) nerve; the second joins the nerves to the subscapularis; the third follows the nerve to the teres major; the fourth follows the nerve to the latissimus dorsi; and the fifth or terminal branches end on the chest wall where they meet the nerve to the serratus anterior.
November 2002. Arch Surg. 2002;137(11):1316. doi:10.1001/archsurg.137.11.1316