Anatomy of the Posterior Triangle of the Neck
Sternocleidomastoid Muscle. It also acts as an accessory muscle of inspiration, along with the scalene muscles of the neck Sternocleidomastoid The triangles of the neck . (Anterior triangles to the left; posterior triangles to the right.) Muscles of the neck. Lateral view. Latin musculus sternocleidomastoideus Gray's subject #111 390 Origin manubrium sterni , medial portion of the clavicle Insertion mastoid process of the temporal bone , superior nuchal line of the occipital bone Artery occipital artery and the superior thyroid artery Nerve motor: accessory nerve sensory: cervical plexus (ventral ramus of the second cranial nerve) Actions Acting alone, tilts head to its own side and rotates it so the face is turned towards the opposite side. Acting together, flexes the neck, raises the sternum and assists in forced inspiration. . The Sternocleidomastoid is crossed by the platysma and the E...