Anterior Scalene, Posterior View

Description

Positioned on the lateral aspect of the cervical spine, the anterior scalene (musculus scalenus anterior) is shown from a posterior perspective in an adult male, with its muscle belly descending inferolaterally from the anterior tubercles of the transverse processes of C3 to C6 toward its insertion on the first rib. Posterior to it, the cervical vertebral arches and spinous processes align in the midline from the atlas (C1) and axis (C2) down to the cervicothoracic junction, while the upper thoracic vertebrae and first ribs frame the inferior field. Clavicles and the superior rib cage sit anteroinferior to the cervical column, establishing the thoracic inlet. Clear landmarks. That posteriorly oriented view matters because it clarifies how the anterior scalene relates to the cervical transverse processes and the first rib, the bony corridor where the subclavian artery and brachial plexus pass between the anterior and middle scalene muscles. This is the anatomy behind scalene-related thoracic outlet syndrome, where hypertrophy or fibrous bands can narrow the interscalene triangle and reproduce neurologic symptoms in the upper limb, and it also guides safe needle trajectory for an interscalene brachial plexus block by keeping the clinician oriented to the vertebral levels and deep muscular planes. Use this artwork in gross anatomy and regional anatomy teaching to anchor the scalenes to C3 to C6 and to the first rib, or in anesthesia and pain medicine materials discussing interscalene block technique and complications near the pleura at the thoracic inlet. It also fits spine and sports medicine publications covering cervicobrachial pain patterns, cervical rib variants, and thoracic outlet differential diagnosis. Anatomical accuracy verified by SciePro's Medical Advisory Board.