The anterior scalene (also anterior scalene muscle, latin: musculus scalenus anterior) is a deep muscle of the lateral part of the neck that lies behind the sternocleidomastoid.
The anterior scalene originates from the anterior tubercles of the transverse processes of the 3rd to 6th cervical vertebrae (C3 - C6). The insertion site of the anterior scalene is the scalene tubercle on the inner border of the first rib.
By contracting on both sides the anterior scalene flexes the neck forward. By contracting on one side it bends the neck laterally.
The anterior scalene is innervated by the anterior rami of the 4th to 7th cervical spinal nerves (C4 - C7).