The sternocleidomastoid (SCM) muscle is one of the most complex in the body. It functions as both a short range (clavicular head) and long range (sternal head) rotator, an upper cervical extensor, a flexor of the cervical spine on the thoracic spine, a lateral flexor, as well as a very important source of equilibrium sense.1,2,3 Likewise, when it becomes dysfunctional as a result of containing myofascial trigger points (TPs), it can present a complex clinical picture.

The pain referral pattern of the SCM includes pain over the cheekbone, in the forehead, on top of the head, in and behind the ear, over the chin, over the SC joint, over the forehead, and deep in the throat.3 The throat referral is a commonly overlooked cause of sore throat, often mistaken for pharyngitis. The patient will often feel a fullness in the throat, especially upon swallowing, which feels like a partial obstruction. The forehead referral pattern is one of the very few instances, if not the only instance, where referred pain can cross the midline, as the pain is frequently felt in the contralateral forehead area in a patient suffering from a TP in the clavicular division of the SCM.

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