Omohyoid Muscle, Gross Anatomy

Description

Arcing across the anterolateral neck, the omohyoid muscle is presented as a two-bellied strap muscle with an inferior belly arising from the superior border of the scapula near the suprascapular notch and crossing superiorly and medially toward the clavicular region. An intermediate tendon lies deep to the sternocleidomastoid and typically anchors to the clavicle by a fascial sling, before the superior belly continues to insert on the inferior border of the hyoid bone lateral to the sternohyoid. Surrounding landmarks in this male upper body rendering include the mandible and hyoid complex superiorly, cervical vertebrae posteriorly, and the clavicle, scapula, and upper ribs laterally and inferiorly. Small muscle, clear landmark. Functionally, the omohyoid tethers and depresses the hyoid during swallowing and phonation, but its anatomic value is often as a landmark in the anterior triangle: the superior belly helps define the carotid triangle and points you to the carotid sheath contents (common carotid artery bifurcation, internal jugular vein, and vagus nerve) deep and slightly posterior. Surgeons also encounter the omohyoid during level III and IV neck dissection, and its intermediate tendon and fascial sling can obscure or guide dissection planes along the internal jugular vein. Awareness of its variable course and occasional absence prevents misidentification of strap muscles when approaching the larynx, thyroid gland, or carotid system. Ideal applications include gross anatomy lab teaching of the infrahyoid (strap) muscles, otolaryngology and head and neck surgery atlases illustrating anterior triangle subdivisions, and radiology teaching files that correlate neck muscle planes on CT and MRI. It also supports patient education graphics for cervical lymph node dissection or carotid endarterectomy by clarifying surface-to-deep relationships at the clavicular root of the neck. Anatomical accuracy verified by SciePro's Medical Advisory Board.