The sternocleidomastoid is a large muscle near the front of the neck. It extends from just under the ear and jaw down to the collarbone. Pain in the sternocleidomastoid can cause neck tenderness and headaches.
A person with sternocleidomastoid pain might notice trigger points along the side or front of the neck. Frequently, however, pain from this muscle radiates elsewhere, causing ear, eye, or sinus pain.
Keep reading to learn more about the causes, diagnosis, and treatment of sternocleidomastoid pain.
The sternocleidomastoid is a superficial muscle, which means that it is just under the skin, not deep in the neck. It attaches to the mastoid process, which is a portion of the bone just behind the jaw and under the ear. The muscle extends down the length of the neck and ends where the collarbone and breastbone connect.
The sternocleidomastoid helps with the movement and balance of the head. The muscle is visible when a person moves their head from side to side. It also plays a role in the rotation, inclination, and extension of the head and neck.
Due to its important role in supporting the head, any issues that affect posture and head position can irritate this muscle. Sudden head movements, blows to the head, and other types of trauma can also cause pain and injuries.
Most people with sternocleidomastoid pain develop the pain slowly due to a combination of lifestyle issues. When this muscle has to hold the head in an awkward position, it can gradually become irritated and sore.
Some causes of sternocleidomastoid pain include:
- carrying a heavy object, such as a child or backpack, in an awkward position
- poor posture, for example, when a person spends long days hunched over a computer or straining their neck to reach things in the garden
- an awkward work station layout that makes a person hold their neck in an uncomfortable position
- tension or injury in other muscles of the shoulders, neck, or back
- holding a phone between the ear and shoulder
- sleeping in an awkward position or on an uncomfortable pillow
Less frequently, some other factors may cause sternocleidomastoid pain. They include:
- Trauma: A fall, blow to the side of the neck, or car accident may injure the neck muscles, causing strains, sprains, and other injuries. A person does not have to fall or experience a serious injury to sustain damage to this part of the body, however. A 2014 case report details a ruptured sternocleidomastoid following an epileptic seizure.
- Arthritis: Arthritis in the spine can cause referred pain in the sternocleidomastoid. It may also cause a person to change their posture or move their head in a way that increases the risk of injury.
- Myofascial pain syndrome: Myofascial pain syndrome is a type of muscle pain that causes trigger points in a muscle. A person may feel pain radiating to other areas when they press on these trigger points. Most people with myofascial pain experience symptoms following an injury or due to chronic lifestyle issues, such as bad posture.
Generally, people with an injured sternocleidomastoid do not feel pain at the site of the injury. Instead, the pain tends to radiate to other areas of the body. The most common symptoms include:
- unexplained ear pain, which may present as soreness, aching, or a sense of fullness in the ear
- pain in the face or the front of the head
- pain in or above the eyes
- throat pain when swallowing
- headaches, including migraine-like headaches
- pain in the sinuses or nose
- neck stiffness, including difficulty rotating the head from side to side
- tingling in the face, head, or neck
A doctor will begin the diagnosis of a sternocleidomastoid injury by asking the person about their symptoms and their recent medical history and activities. It is important to tell the doctor about all symptoms, even if they seem unrelated, as injuries to this muscle can cause a wide variety of seemingly unrelated symptoms.
The doctor will then carry out a physical examination, asking the individual to perform voluntary movements. These may reveal tenderness or stiffness in the muscle due to bad posture, chronic muscle weakness, or lifting heavy objects.
Imaging scans may be necessary for the doctor to get a detailed view of the muscles and surrounding structures. An ultrasound can help them diagnose trauma to the sternocleidomastoid, while an X-ray can rule out broken bones.
Various treatments are available for sternocleidomastoid pain, with the type and cause of the injury determining the best option. Possible treatment approaches include:
- Lifestyle changes: When bad posture or carrying heavy objects causes sternocleidomastoid pain, addressing this issue can prevent the pain from getting worse.
- Pain management: Rest, ice, heat, and nonsteroidal anti-inflammatory drugs may help reduce pain. Some people find that alternating heat and ice is helpful.
- Physical therapy: Physical therapy can help a person regain strength in the neck and head. It can also help prevent chronic injuries.
- Surgery: If other treatments fail, a person may need surgery, especially if the sternocleidomastoid ruptures or tears.
- Chiropractic care: Chiropractic care is among the alternative treatments that may help reduce pain for some people.
Gentle stretches and exercises can help restore strength to the neck and reduce stiffness. It is important to talk to a doctor or physical therapist before exercising. Some exercises may make the injury worse, especially if a person does not use the correct technique.
The following exercises may help with neck pain:
- Cervical flexion: Sit upright on a chair and slowly tilt the head forward and then back again. Repeat this movement several times, but keep it steady to avoid additional strain.
- Cervical side flexion: Sit upright on a chair and slowly tilt the head to one side and then the other. Repeat this movement in a controlled manner.
- Cervical rotation: Sit upright on a chair and slowly rotate the head to face one side and then the other. Repeat this movement several times, only turning the head as far as is comfortable.
- Chin tucks: Sit upright on a chair and slowly draw the chin inward while keeping the head straight. Keep the repetitions steady to avoid straining the neck further.
A person might not notice a sternocleidomastoid injury because the symptoms typically spread to the head and face.
In many cases, they might think that they have an ear infection, migraine episode, eye health issue, or another unrelated issue. It is, therefore, important to see a doctor for any unexplained health symptoms.
With appropriate treatment, sternocleidomastoid pain usually goes away.