The sternocleidomastoid muscle is one of the largest muscle of the cervical. This muscle originate directly from the sternum and clavicle. This show insertion in the skull's temporal bone.
The major function of this muscle is the opposite rotation of the head and also do the flexion of the neck. This muscle also helps in the oblique rotation of the head and do the extension of the head. This muscle also acts as the accessory muscle of the respiration.
