Anatomical Structure and Location of the Neck Muscles Beneath the Skin

Description

Lateral profile anatomy of the male neck layers the platysma superficially over the sternocleidomastoid, whose sternal and clavicular heads run obliquely from the manubrium and medial clavicle to the mastoid process and superior nuchal line. Posterior to it, the upper trapezius slopes inferiorly toward the lateral clavicle and acromion, while the anterior and middle scalene muscles descend from the cervical transverse processes to the first rib, forming the interscalene interval deep to the sternocleidomastoid. Inferior and medial in the anterior neck, the hyoid sits superior to the thyroid cartilage region, with the infrahyoid strap muscles (sternohyoid, omohyoid, sternothyroid, thyrohyoid) oriented mainly in a superior to inferior course toward the manubrium, clavicle, and scapular attachment via the omohyoid. Cervical vertebrae appear posterior, with the clavicle and part of the scapula anchoring the shoulder girdle beneath the muscular plane. Clinically, this side-on arrangement helps you teach surface landmarks that guide airway access and regional anesthesia: the sternocleidomastoid borders the anterior and posterior cervical triangles, and its posterior edge is a common reference for locating the cervical plexus for superficial cervical plexus block. The scalene group and first rib relationship is central to thoracic outlet syndrome, where brachial plexus elements and the subclavian artery can be compressed in the interscalene triangle, and it also explains why interscalene brachial plexus blocks risk phrenic nerve palsy with hemidiaphragm elevation. Small distances matter. Use this artwork for head and neck anatomy courses, surgical atlases illustrating neck triangle dissection, and otolaryngology or anesthesia teaching materials that link palpable landmarks to deeper structures from the hyoid to the clavicle. Anatomical accuracy verified by SciePro's Medical Advisory Board.