I am always astounded by the amount of massage therapists that do not address the sternocleidomastoid, known as SCM for short, muscle in the neck. The SCM is one of the largest and most superficial cervical muscles and it divides the neck into anatomical anterior and posterior triangles. Responsible for flexing and rotating the head, it is named by the anatomical origin and insertion points, being Sterno- (refers to the sternum), Cleido- (the clavicle, or collarbone), and -Mastoid (the mastoid process, a bony knob behind the ear).
When this muscle is really tight and produces "active" trigger points, which are irritable localized spots of exquisite tenderness that refer pain, the SCM can cause moderate symptoms. These symptoms include headaches, dizziness, blurred vision, ear pain, postural imbalance, jaw and sinus pain, teeth hypersensitivity, stiff neck, chronic cough, and sore throat.