Muscles of the Neck

Muscles of the Neck Cervical muscles Muscle - Platysma Origin - Superficial fascia over upper part of deltoid and pectoralis major Insertion - Mandible; skin and muscles over mandible and angle of mouth Nerve - Facial nerve Action - Depresses lower jaw and lip and angle of mouth; wrinkles skin of neck Muscle - Sternocleidomastoid Origin - Manubrium sterni and medial one third of clavicle Insertion - Mastoid process and lateral one half of superior nuchal line Nerve - Spinal accessory n.; C2–C8 (sensory) Action - Singly turns face toward opposite side; together flex head, raise thorax Suprahyoid muscles Muscle - Digastric Origin - Anterior belly from digastric fossa of mandible; posterior belly from mastoid notch Insertion - Intermediate tendon attached to body of hyoid Nerve - Posterior belly by facial nerve.; anterior belly by mylohyoid nerve. of trigeminal nerve. Action - Elevates hyoid and floor of mouth; depresses mandible Muscle - Mylohyoid Origin - Mylohyoid line of mandible Insertion - Median raphe and body of hyoid bone Nerve - Mylohyoid nerve. of trigeminal nerve. Action - Elevates hyoid and floor of mouth; depresses mandible Muscle - Stylohyoid Origin - Styloid process Insertion - Body of hyoid Nerve - Facial nerve. Action - Elevates hyoid Muscle - Geniohyoid Origin - Genial tubercle of mandible Insertion - Body of hyoid Nerve - C1 via hypoglossal nerve. Action - Elevates hyoid and floor of mouth Infrahyoid muscles Muscle - Sternohyoid Origin - Manubrium sterni and medial end of clavicle Insertion - Body of hyoid Nerve - Ansa cervicalis Action - Depresses hyoid and larynx Muscle - Sternothyroid Origin - Manubrium sterni; first costal cartilage Insertion - Oblique line of thyroid cartilage Nerve - Ansa cervicalis Action - Depresses hyoid and larynx Muscle - Thyrohyoid Origin - Oblique line of thyroid cartilage Insertion - Body and greater horn of hyoid Nerve - C1 via hypoglossal n. Action - Depresses hyoid and elevates larynx Muscle - Omohyoid Origin - Inferior belly from medial lip of suprascapular notch and suprascapular ligament; superior belly from intermediate tendon Insertion - Inferior belly to intermediate tendon; superior belly to body of hyoid Nerve - Ansa cervicalis Action - Depresses and retracts hyoid and larynx ◄.....Go back to the Gross Anatomy homepage