ANATOMY

Detailed explanation-1: -They arise from the anterolateral surface of the manubrium sterni and the medial third of the superior surface of the clavicle, respectively. The thickness of the CH is variable. The two heads are separated by a triangular surface depression, the lesser supraclavicular fossa.

Detailed explanation-2: -It originates on the anterior surface of the manubrium, and the superior border and anterior surface of the medial third of the clavicle. The SCM converges into one point and inserts on the lateral surface of the mastoid process and the nuchal line of the occipital bone.

Detailed explanation-3: -The sternocleidomastoid muscle is a two-headed neck muscle, which true to its name bears attachments to the manubrium of sternum (sterno-), the clavicle (-cleido-), and the mastoid process of the temporal bone (-mastoid).

Detailed explanation-4: -The clavicular head of the sternocleidomastoid muscle is the more lateral and posterior of the two heads of origin of the sternocleidomastoid muscle. It connects the skull to the clavicle and allows the head to flex or rotate.

Detailed explanation-5: -The sternocleidomastoids (SCMs) are superficially located neck muscles that play an important role in tilting your head and turning your neck, as well as other movements. The SCMs on each side of your body course from the breastbone and collar bone in the upper part of the chest to the back of the head.