Sternocleidomastoid (SCM) is an unusual muscle. It has the ability to create movements in many directions. It has two bellys the anterior and posterior, with each performing a slightly different role in terms of movement. The posterior portion performing more of the side bending movement and the anterior more of the head rotation/protraction. The muscle is easy to find by turning your head to one side, the muscle engage and you will see it run from behind your ear to your collarbone.
Action: Unilaterally: head rotation to opposite side of muscle, side bending to same side as muscle
Bilaterally: Forward bending of neck, elevation of sternum and assists in forced inhalation
Origin: Manubrium and medial portion of the clavicle
Insertion: Mastoid process of the temporal bone, superior nuchal line
Accessory nerve: cranial nerve XII and ventral rami of the (C2, C3)
Anectdotally it has been a problem for people suffering from headaches. Most commonly I have seen office workers and people that clench or grind their teeth come into the clinic with discomfort being referred from their SCM. Especially people with a deskbound job that are leaning forward, looking at the computer screen. Typically clients have presented with headaches around the temple or forehead.
Often overlooked during treatment, tightness in your SCM can refer pain and discomfort in many areas of the head. It is a relatively simple muscle to treat. Easy to access to self treat but if you are at all unsure then seek treatment from a health professional.
As you can see from the below picture there are up to seven common points that can refer discomfort around the neck and head. There are 3 in the posterior belly and 4 in the anterior belly. The red areas indicating the common referral patterns with a problematic SCM.
Ways to ease tension in your SCM:
Strenghtening: Unilateral: Using a theraband around your head and anchored to something, turn your head to the right. Keep on the same side until finished the change sides.
Using a theraband around one side of your head and anchored to something, side bend your head away from the anchor point.
Bilateral: Using a theraband around the front of your head and anchored to something, push your head and bend your neck slightly forward at the same time.
Stretching: To stretch the right muscle, turn your head to the left. Put the heel of your left thumb (thenar eminence) at the attachment of your right SCM. Put your right hand on top of your left to apply extra pressure. Keeping your head turned to the left lean your head back. You should then feel a nice strong stretch in your SCM.
Self Massage: Lying with your head on a pillow turn your head to the right. Put your hand on your left SCM as you are turning your head to make sure you are on the correct muscle. You will feel it pop up or tighten. Gently massage the muscle with the pads of your fingers in small circular motions. Turn your head to the left and repeat the steps again but on your right SCM.
Always consult a health professional before performing any of these suggestions to see if they are correct for your situation.