Sternocleidomastoid muscle :-
Muscle details :-
It is one of the largest and most superficial cervical muscles. The primary actions of the muscle are rotation of the head to the opposite side and flexion of the neck. The sternocleidomastoid is innervated by the accessory nerve.
Manubrium and medial portion of the clavicle .
Mastoid process of the temporal bone, superior nuchal line .
Motor: spinal accessory nerve .
Unilaterally: contralateral cervical rotation, ipsilateral cervical flexion .
-Bilaterally: cervical flexion, elevation of sternum and assists in forced inhalation .