Deep branch of transverse cervical artery

The dorsal scapular artery (or descending scapular artery) is a blood vessel which supplies the levator scapulae, rhomboids, and trapezius. 

It most frequently arises from the subclavian artery (the second or third part), but a quarter of the time it arises from the transverse cervical artery. In that case, the artery is also known as the deep branch of the transverse cervical artery (this explains the two different entries in the Terminologia Anatomica), and the junction of those two is called cervicodorsal trunk. It passes beneath the levator scapulae to the superior angle of the scapula, and then descends under the rhomboid muscles along the vertebral border of the scapula as far as the inferior angle.