Circumflex scapular artery

At a glance

English

Circumflex scapular artery

Latin (TA2)

Arteria circumflexa scapulae

System

Artery

Region

Trunk

Side

Paired, left and right

About the circumflex scapular artery

The circumflex scapular artery, also called the scapular circumflex or dorsal scapular branch in older texts, is the larger of the two branches into which the subscapular artery divides; the other is the thoracodorsal artery. The subscapular artery itself is the largest branch of the axillary artery, arising from its third part at the lower border of subscapularis.

From its origin the vessel turns backwards and passes through the triangular space, a small gap on the back of the axilla bounded above by teres minor, below by teres major and laterally by the long head of triceps. It then curls round the lateral (axillary) border of the scapula, grooving the bone, and comes to lie in the infraspinous fossa beneath teres minor and infraspinatus.

During its course it gives a branch to the subscapular fossa, which runs under subscapularis and supplies it, and a branch that continues down the scapula's lateral border between the two teres muscles to the inferior angle. Small twigs go to the back of the deltoid and to the long head of triceps, and these meet ascending twigs of the deep brachial artery. In the infraspinous fossa its branches link with the suprascapular artery and with the dorsal scapular artery (the deep branch of the transverse cervical artery when that is present).

These connections form the scapular anastomosis, a ring of vessels round the shoulder blade joining the first part of the subclavian artery with the third part of the axillary artery. When the axillary or subclavian artery is slowly blocked between these points, blood can still reach the arm through this ring. The vessel also supplies the skin of the back over the scapula and is the basis of the scapular and parascapular skin flaps used in reconstructive surgery.

Course and supply

Arises from

Arises from the subscapular artery, a branch of the third part of the axillary artery, together with the thoracodorsal artery.

Ends in

Ends in the infraspinous fossa, where it joins the suprascapular and dorsal scapular arteries in the scapular anastomosis.

Supplies

Supplies subscapularis, teres major and minor, infraspinatus, the posterior deltoid, the long head of triceps and the skin over the scapula.