Thyrohyoideus Muscle

Description

Arising from the oblique line of the thyroid cartilage, the paired thyrohyoideus muscles ascend in the anterior neck to insert on the inferior border of the body of the hyoid bone and its greater horn. Each muscle sits deep to the sternohyoideus and omohyoideus and superficial to the thyrohyoid membrane and laryngeal framework, with right and left bellies separated by the midline interval over the larynx. Superiorly, the hyoid is suspended beneath the mandible and skull base, while posteriorly the cervical vertebrae provide the bony backdrop for the infrahyoid strap layer. Functionally, thyrohyoideus bridges swallowing and phonation by depressing the hyoid when the larynx is fixed, or elevating the larynx toward the hyoid when the hyoid is stabilized. That distinction matters in dysphagia assessment and in teaching hyolaryngeal excursion, where reduced laryngeal elevation contributes to impaired airway protection. The muscle also serves as a surgical landmark during anterior approaches to the larynx and thyroid cartilage, and it lies in the neighborhood of the internal branch of the superior laryngeal nerve as it pierces the thyrohyoid membrane. Small muscle. Big payoff for orientation. Use this artwork in head and neck anatomy courses to clarify the infrahyoid layer, in ENT and speech language pathology teaching modules on deglutition mechanics, or in surgical atlases discussing laryngeal exposure and the thyrohyoid membrane region. Anatomical accuracy verified by SciePro's Medical Advisory Board.