The sternocleidomastoid or SCM muscle is a complex neck muscle that crosses may joints.
The SCM muscle produces multi-directional movement. Problems can cause neck, head, jaw, and sternum pain.
It attaches to the back of the head on the mastoid process to the sternum (superficial) and clavicle (deep). It is subject to problems from poor sleeping and working postures. It is subject to chronic strain and formation of trigger points. This can also cause problems like throat, eye and face pain, sometimes called atypical facial neuralgia. The head pain referral may often be mistaken for tension headaches.
The sinuses and even ear pain may be cases as result of referred pain from trigger points in the sternocleidomastoid muscle. It may also cause dizziness due to posture and disturbed equilibrium. The SCM also acts as an accessory muscle for respiration. An example of irritation would be use of holding a phone in the shoulder without hands. This gives an idea of the complex action of the muscle.
- A 2021 study in Musculoskeletal Science & Practice revealed massage and stretching of the sternocleidomastoid muscle reduced pain and disability, as well as increases range of motion and muscle endurance in those with chronic neck pain.
- A 2013 study in the Journal of Manipulative and Physiological Therapeutics found patients receiving trigger point therapy showed reduction in neck pain and headache and experienced greater improvements in motor performance of the deep cervical flexors, active cervical range of motion and pain pressure thresholds. The findings show this form of treatment to be effective for cervicogenic headaches.
Congenital muscular torticollis is a common postural deformity evident shortly after birth, typically characterized by one side cervical lateral flexion (side bending) and cervical rotation to the opposite side and is caused by one sided shortening of the sternocleidomastoid muscle. This condition is found in adults as well.
Together, the muscles help to prevent hyperextension of the head and forceful backward motion often seen in whiplash injuries. Along with the trapezius muscle, they help stabilize the head when the jaw moves during talking and eating. The SCM is also involved in swallowing.
SCM Muscle Treatment & Corrective Action
When lying down don’t pull the head straight up. Unload the muscle by turning the head to the opposite side first. When sleeping, don’t lift the head to change positions, roll the head on the pillow. Maintaining correct spinal posture while sleeping by using ergonomic pillows is helpful and functional pillows can help prevent excessive head rotation.
Correction of forward head posture is important to prevent the head from protruding forward, so keep the head in the proper position when sitting and standing. Avoid using smartphones as much as possible. A lumbar support while sitting can help overall posture while sitting.
Do not swim using the crawl stroke that can strain the SCM muscle. Activities that require long term extension like working overhead should be supported. Do not wear a tight shirt collar – a finger should fit comfortably in the collar with the head straight and rotated. A necktie should not be to tight to avoid constriction of the muscle.
Treatment using massage, stretching and trigger point therapy is usually effective. If you do not feel comfortable doing this on your own, consult a professional. Moist heat applied to the muscle before treatment is helpful. You can use a hot shower or a moist heating pad designed for the neck. Learn correct breathing techniques.
These videos should be helpful for self treatment.