Sternothyroid Muscles

Description

Rendered from a lateral aspect of the male head and neck, the strap musculature is centered on the sternothyroid muscle, arising from the posterior surface of the manubrium sterni and adjacent first costal cartilage and ascending superiorly toward the oblique line of the thyroid cartilage. Its broad belly lies deep to the sternocleidomastoid and typically deep to, and partly overlapped by, sternohyoid, with the laryngeal framework positioned anterosuperior to the sternal origin. Superiorly, the sternothyroid approaches the larynx just inferior to the hyoid level, while nearby superficial facial and masticatory muscles (temporalis, masseter, orbicularis oculi) provide orientation in the lateral profile of the head. Fiber direction is clear. This view matters when teaching the infrahyoid (strap) muscles as depressors of the larynx and hyoid during swallowing and phonation, because the sternothyroid acts directly on the thyroid cartilage rather than the hyoid, distinguishing it functionally from sternohyoid and omohyoid. Surgeons encounter and often split or retract these muscles in midline approaches to the thyroid gland and upper trachea, so appreciating their relationship to the laryngeal prominence and suprasternal notch helps plan thyroidectomy exposure and emergency tracheostomy. In anterior neck trauma or postoperative neck hematoma, strap muscle displacement can also change palpable landmarks, complicating airway assessment. Use this illustration in gross anatomy and head and neck courses to anchor strap muscle layering in a lateral teaching plate, or in endocrine surgery and otolaryngology materials to explain surgical planes, strap muscle retraction, and postoperative voice or swallowing complaints tied to laryngeal depression mechanics. It also suits patient-facing education where a clear lateral neck muscle map supports explanation of thyroid and airway procedures. Anatomical accuracy verified by SciePro's Medical Advisory Board.