The sternocleidomastoid (SCM) muscle is one of the most complex muscles in the body. Dysfunction of the SCM can produce pain in the neck, throat, headaches, numbness/tingling in the face, head or neck, disequilibrium and balance deficits as well as blurred vision, conjunctivitis and eyelid drooping.
The SCM has two components the clavicular head and sternal head. Both muscles originate from the superior nuchal line along the back of the skull. The clavicular portion attaches to the posterior and lateral part of the clavicle and the sternal portion attaches below the sternal notch. The SCM is a unique muscle because it works both bilaterally and unilaterally. Unilaterally, the SCM causes side bending to the same side and turning the head to the opposite side. Bilaterally it causes the head to bend forward at the lower cervical level, and the head to extend at the upper cervical level.
Muscles can develop “trigger points”, which are very tight, rope-like bands of muscle that are sensitive to pressure. The pain from these trigger points is usually reported as dull and aching, until pressed which can cause referred pain patterns extending away from the trigger point. Trigger points in the clavicular division of the SCM can cause referred pain to the eye, the chest, the cheek and is important in the sense of equilibrium and balance. Trigger points in the sternal portion of SCM can cause in the forehead, behind the ear and is frequently involved in chronic headaches.
Physical therapy can be an effective tool to treat SCM syndrome. The use of specific stretches designed to reduce muscle tension are easy ways to improve symptoms at home. Trigger point release through ischemic compression techniques by a therapist can help improve trigger points and reduce muscle tension type headaches. Exercise to improve posture can help reduce risk of overuse of the SCM.
It is important to see a physician for any new headache or dizziness symptoms as they can be related to a more severe condition.