The posterior humeral circumflex artery (posterior circumflex artery or posterior circumflex humeral artery[citation needed]) arises from the third part of the axillary artery at the distal border of the subscapularis.

[1] It passes posteriorward with the axillary nerve through the quadrangular space.

It winds laterally around the surgical neck of the humerus.

[1] It is distributed to the shoulder joint,[1] teres major, teres minor, deltoid,[1][2] and (long and lateral heads of) triceps brachii.

[1] This article incorporates text in the public domain from page 589 of the 20th edition of Gray's Anatomy (1918)