Sternothyroid Muscles Beneath the Skin, Lateral View

Description

Viewed in lateral profile, the sternothyroid lies deep to the sternohyoid within the infrahyoid (strap) muscle layer, running superiorly from the posterior manubrium and first costal cartilage to the oblique line of the thyroid cartilage. Anterior to it, the skin and superficial fascia soften the contours, while the sternocleidomastoid forms a more lateral superficial boundary from the mastoid process to the sternum and clavicle. Superiorly, the laryngeal framework is suggested beneath the overlying soft tissues, with the sternothyroid positioned inferior to the thyroid cartilage and medial to the more lateral scalene region. Posteroinferiorly, the upper thoracic inlet and anterior chest wall musculature, including pectoralis major, set the proximal context for these depressor muscles of the larynx. This relationship matters when teaching or operating in the anterior neck, because the strap muscles are the first muscular layer encountered in tracheostomy and in thyroidectomy before the thyroid gland and trachea come into view. Strap muscle tightness or postoperative scarring can tether the larynx, contributing to dysphagia or altered voice mechanics, and the sternothyroid itself can be partially divided or retracted to improve exposure of the thyroid lobe and the superior pole. A clean lateral view clarifies how a laryngeal depressor sits immediately adjacent to the thyroid cartilage, where superior laryngeal nerve injury becomes a real concern during superior pole dissection. Use this artwork in gross anatomy labs and head and neck modules to explain infrahyoid layering, or in ENT and endocrine surgery publications that need accurate orientation cues for anterior neck approaches. It also supports patient education materials describing why the voice and swallowing can change after neck surgery. Anatomical accuracy verified by SciePro's Medical Advisory Board.