Sternohyoid Muscles

Description

Rendered in a left anterior oblique (three-quarter) view of an adult male head, neck, and upper thorax, the paired sternohyoid muscles form the medial infrahyoid strap muscles, running superiorly from the posterior surface of the manubrium and medial clavicle to their insertion on the inferior border of the hyoid bone. Lateral to the sternohyoid, the sternocleidomastoid stands out as the dominant superficial cervical landmark, with the trapezius sweeping posterolaterally toward the shoulder girdle. Deep to the sternocleidomastoid, the course of the common carotid artery ascending toward the bifurcation and the internal jugular vein are emphasized, placing the carotid sheath contents immediately lateral and slightly posterior to the strap muscle plane. Sternohyoid anatomy matters because it defines the midline approach to the visceral compartment of the neck, including the larynx, trachea, and thyroid gland, and it sets the working corridor for procedures such as tracheostomy and thyroidectomy where strap muscle splitting or retraction is routine. The oblique angle is useful for teaching how the carotid artery and jugular vein sit deep to the sternocleidomastoid while the infrahyoid strap muscles remain more medial, a relationship that helps explain why lateral neck dissection respects the carotid sheath and why midline entry avoids it. Clean landmarks. Use this asset for gross anatomy and head and neck surgery teaching, for an atlas figure on the infrahyoid muscles and carotid sheath relationships, or for clinical education materials covering airway access, thyroid surgery exposure, and anterior cervical compartment anatomy in an adult male. Anatomical accuracy verified by SciePro's Medical Advisory Board.