Anterior Scalenes Beneath the Skin, Anterior View

Description

Anterior neck integument has been removed to expose the paired sternocleidomastoid muscles and the underlying anterior scalene muscles arising from the anterior tubercles of the transverse processes of C3 to C6. Each anterior scalene descends inferolaterally to its insertion on the scalene tubercle of the first rib, immediately superior to the rib’s costal cartilage and medial to the clavicle and manubrium. Midline skeletal landmarks remain prominent, including the mandible, maxilla, cervical vertebral column, sternum, and upper ribs. Clear orientation. An anterior view like this matters because the anterior scalene defines the interscalene triangle and frames the passage of the brachial plexus trunks and the subclavian artery, while the subclavian vein runs anterior to the muscle, a relationship that explains why a needle trajectory for supraclavicular access can drift into vascular or pleural territory when landmarks are misread. The phrenic nerve typically courses on the anterior surface of the anterior scalene, so hypertrophy, spasm, or injection around this muscle can produce diaphragmatic paresis, and fibrous bands at the first rib insertion contribute to neurogenic thoracic outlet syndrome. Small distances here have consequences. Use this illustration to teach surface-to-deep anatomy in head and neck dissection labs, to clarify scalene attachments and first-rib landmarks in respiratory mechanics modules, or to accompany clinical text on thoracic outlet syndrome, interscalene brachial plexus block, and complications of central venous catheterization near the clavicle and first rib. It also fits well in surgical anatomy references discussing supraclavicular approaches to the brachial plexus and subclavian vessels. Anatomical accuracy verified by SciePro's Medical Advisory Board.