Anatomical Structure and Location of the Sternothyroid Under the Skin

Description

Running vertically in the anterior neck, the sternothyroid lies deep to the sternohyoid as one of the infrahyoid strap muscles. Its inferior attachment occupies the posterior surface of the manubrium and adjacent first costal cartilage near the sternoclavicular region, then the muscle belly ascends superiorly to insert along the oblique line of the thyroid cartilage. Superior to it, the hyoid bone is suspended at the level of C3, while the mandible with dentition and the upper cervical vertebrae provide bony context posteriorly. A stout midline muscle. Functionally, sternothyroid depresses the larynx after elevation during swallowing, and it can steady the thyroid cartilage during phonation, so its relationship to the laryngeal framework matters in both teaching and operative anatomy. The muscle is encountered in anterior neck dissection and in surgical corridors used for thyroidectomy and tracheostomy, where the strap muscles are separated and retracted to expose the thyroid gland and trachea. Recognizing sternothyroid as deeper and more lateral than sternohyoid helps clarify why it is often divided or mobilized when superior pole access is limited, and why postoperative strap muscle fibrosis can affect voice and swallowing mechanics. Use this asset in head and neck anatomy modules (infrahyoid compartment and laryngeal framework), in endocrine surgery atlases illustrating midline strap muscle approach to the thyroid, or in speech and swallowing teaching materials that link laryngeal elevation and depression to specific muscle actions. It also fits well in patient education for thyroid and airway procedures where a clear depiction of the sternum, clavicles, and laryngeal cartilages improves procedural orientation. Anatomical accuracy verified by SciePro's Medical Advisory Board.