The subclavian artery is so called because it is located beneath the clavicle. It is the main source of blood supply to the upper limb and hence called artery of the upper limb. However, the subclavian artery also supplies considerable part of the thoracic wall, head, neck, and brain through its branches.
Dorsal Scapular Artery
It appears from the 3rd part of the subclavian artery (but may be the deep branch of the transverse cervical artery). As a direct branch of the subclavian artery, it enters laterally and backwards between the trunks of brachial plexus to reach underneath the levator scapulae. Now it descends along the medial border of the scapula in business with dorsal scapular nerve deep to rhomboids and takes part in the formation of arterial anastomosis around the scapula.
In total there are two common carotid arteries: right and left. They are the main arteries of the head and neck.
Common Carotid Artery
The common carotid artery has only two terminal branches which are external and internal carotid arteries.
External Carotid Artery
It is one of the two terminal branches of the common carotid artery and supplies the structures external to the head and in front of the neck.
Internal Carotid Artery
The internal carotid artery is one of the two terminal branches of the common carotid artery but it is more direct. It is considered as an upward continuation of the common carotid artery.