Origin: Transverse process of C3-C6
Insertion: First rib
Artery: Ascending cervical artery (branch of inferior thyroid artery)
Nerve: Ventral ramus of C5, C6
The Scalenus anterior (Scalenus anticus) lies deeply at the side of the neck, behind the Sternocleidomastoideus.
It arises from the anterior tubercles of the transverse processes of the third, fourth, fifth, and sixth cervical vertebrae, and descending, almost vertically, is inserted by a narrow, flat tendon into the scalene tubercle on the inner border of the first rib, and into the ridge on the upper surface of the rib in front of the subclavian groove.