ANATOMY

Detailed explanation-1: -The sternocleidomastoid muscle protects some of the deeper structures, including the carotid artery and jugular vein. It also rotates the head and allows for neck flexion. Plus, the SCM supports the head when you move it back and helps with chewing and swallowing.

Detailed explanation-2: -Function. A unilateral contraction of the sternocleidomastoid muscle flexes the cervical vertebral column to the same side (lateral flexion) and rotates the head to the opposite side.

Detailed explanation-3: -Sternocleidomastoid is the most superficial and largest muscle in the front portion of the neck. It is also known as SCM or Sternomastoid or Sterno muscle. The name has the origin of the Latin words: sternon = chest; cleido = clavicle and the Greek words: mastos = breast and eidos = shape, form.

Detailed explanation-4: -Function. Rotation of the head to the opposite side or obliquely rotate the head. It also flexes the neck. When acting together it flexes the neck and extends the head.

Detailed explanation-5: -Sternocleidomastoid: head/neck extension at atlantooccipital joint/ superior cervical spine; neck flexion at inferior cervical vertebrae; elevation of clavicle and manubrium of the sternum at the sternoclavicular joint; ipsilateral flexion and contralateral rotation of the neck at the cervical spine.