Sternothyroid Muscle, Lateral View

Description

Emerging from the posterior surface of the manubrium sterni and adjacent first costal cartilage, the sternothyroid muscle ascends in the anterior neck as a flat infrahyoid strap muscle. In lateral profile, its fibers pass superiorly and slightly posteriorly to insert on the oblique line of the lamina of the thyroid cartilage, lying deep to sternohyoid and inferior to the hyoid bone. The thyroid cartilage sits superior to the sternum, with the cricoid cartilage immediately inferior, and the muscle’s superior attachment is positioned anterolateral to the laryngeal lumen. Clear fascial planes separate the strap musculature from deeper pretracheal contents. A lateral view of sternothyroid matters because it clarifies how infrahyoid tension depresses the laryngeal framework during swallowing and phonation. Surgeons encounter and often divide or retract strap muscles in midline and lateral cervical approaches, including thyroidectomy and tracheostomy, where sternothyroid can obscure the thyroid gland and anterior trachea and where bleeding from the anterior jugular venous territory can complicate exposure. Precise orientation also helps when teaching the relationship between thyroid cartilage landmarks and adjacent muscles in laryngeal examination. Use this asset for head and neck anatomy instruction (infrahyoid region), operative anatomy figures in endocrine surgery or otolaryngology texts, and patient education graphics explaining strap muscle retraction during thyroid surgery. It also fits radiology and cross sectional anatomy modules as a surface anatomy reference for correlating laryngeal cartilages to overlying musculature. Anatomical accuracy verified by SciePro's Medical Advisory Board.