Omohyoid Muscle Beneath the Skin, Anterior View

Description

Running obliquely across the anterolateral neck, the omohyoid is seen as a thin infrahyoid strap muscle with an inferior belly arising from the superior border of the scapula near the suprascapular notch and coursing anterosuperiorly toward the clavicle. An intermediate tendon lies superior to the clavicle and is tethered to the deep cervical fascia by a fascial sling, after which the superior belly ascends medial to the sternocleidomastoid to insert on the inferior border of the hyoid bone, lateral to the sternohyoid. Superficial layers include platysma and the investing layer of deep cervical fascia; deep to the superior belly sit the carotid sheath contents, with the common carotid artery and internal jugular vein suggested by the red arterial emphasis. Small but specific. Clinically, the omohyoid is a practical surface-oriented landmark during anterior triangle work, because the superior belly crosses near the carotid bifurcation region and often overlies or borders the internal jugular vein used for central venous access. During selective neck dissection, the muscle helps partition levels III and IV, and its intermediate tendon region is encountered when elevating the investing fascia and identifying the ansa cervicalis branches that supply the infrahyoid muscles. An unusual but teachable entity is omohyoid syndrome, in which the intermediate tendon and fascial sling can produce a transient lateral neck swelling with swallowing. Educators will find this anterior, subcutaneous rendering well suited for head and neck anatomy labs, surgical anatomy handouts for otolaryngology and endocrine surgery, and atlas plates that need the omohyoid’s two-belly configuration in context with sternocleidomastoid, hyoid, clavicle, and carotid vasculature. It also supports patient-facing diagrams explaining central line placement landmarks and neck dissection field orientation. Anatomical accuracy verified by SciePro's Medical Advisory Board.