Structure passes through upper triangular space:
Profunda brachii
Anterior circumflex humeral aery
Posterior circumflex humeral aery
Circumflex scapular aery
Upper Quadrangular spaceIt has the following boundaries:- the teres major inferiorly- the long head of the triceps laterallyFor the superior border, some sources list the teres minor, while others list the subscapularis.It contains the scapular circumflex vessels.