Neck pain is a widespread issue, but when discomfort is focused on the front and sides of the neck, the sternocleidomastoid (SCM) muscle is often the culprit. This muscle is responsible for a variety of head and neck movements, meaning strain or injury can cause a range of symptoms. Understanding why this muscle hurts is the first step toward finding effective relief and preventing future episodes.
Identifying the Sternocleidomastoid Muscle
The sternocleidomastoid (SCM) is a pair of large, superficial muscles running along the sides of the neck. Its name is derived from its three points of attachment: the sternum (sterno-), the clavicle (cleido-), and the mastoid process (-mastoid) of the skull, the bony bump just behind the ear. This rope-like structure is easily visible when the head is turned to the opposite side.
The SCM performs several important functions related to head and neck movement. When both muscles contract together, they help flex the neck, causing the head to nod or bring the chin toward the chest. When one side contracts, it causes the head to rotate to the opposite side and tilt toward the contracting muscle. The muscle also assists in respiration by helping to elevate the chest during labored breathing.
Primary Drivers of SCM Pain
Pain in the SCM muscle arises from two broad categories of stress: sudden, acute injuries and chronic, repetitive strain. Acute injuries often involve rapid, forceful movements that overstretch or tear the muscle fibers. A common example is whiplash, which occurs during car accidents when the head is suddenly jerked back and forth, placing severe strain on the SCM.
Sleeping in an awkward position, where the neck is sharply turned or bent for hours, can lead to an acute strain felt upon waking. Activities that require working overhead, such as painting or carpentry, can cause strain from prolonged muscle contraction. Sudden, forceful movements like a quick turn of the head may also trigger pain in an already tense muscle.
Chronic postural stress is the most frequent cause of SCM tension in modern life. Maintaining a forward head posture, commonly known as “tech neck,” keeps the SCM in a constantly shortened and contracted state. This prolonged contraction reduces blood flow and can lead to the formation of myofascial trigger points, which are hyperirritable spots within the muscle.
Muscle tension can also be driven by stress-related clenching of the jaw or chronic respiratory issues, such as severe coughing or asthma, which engage the SCM to assist in breathing. Another condition affecting the SCM is torticollis, sometimes called “wry neck.” Torticollis involves the muscle being in a state of spasm or contracture, causing the head to be persistently tilted and turned to one side, making the SCM chronically painful and stiff.
Immediate Relief and Home Management
For mild SCM pain not resulting from severe trauma, gentle self-care measures can provide relief. Thermal therapies, specifically alternating heat and cold, help manage inflammation and muscle relaxation. Applying an ice pack for 15 to 20 minutes can reduce acute inflammation if the pain is new. Following this with a heating pad promotes blood flow and helps relax tight muscle fibers.
Gentle stretching is an effective way to lengthen the muscle and restore mobility, but movements must be slow and controlled. A simple stretch involves slowly tilting the head toward one shoulder while keeping the opposite shoulder relaxed and down. Another technique is to slightly turn the head away from the painful side and then gently tilt the chin upward, which targets the SCM fibers.
Light massage and trigger point release can be performed at home to alleviate localized knots. Carefully pinching the SCM muscle between the fingers and applying light pressure to tender spots for 30 seconds helps release tension. Incorporating ergonomic adjustments, such as ensuring your computer screen is at eye level, helps maintain a neutral head position throughout the day. These actions are intended for uncomplicated muscle soreness and should not be used to treat severe or worsening pain.
When to Seek Professional Help
While many cases of SCM pain resolve with home care, certain symptoms require a medical evaluation to rule out more serious underlying issues. Seek professional help if the pain is persistent and does not improve after about a week of self-treatment, or if the pain is progressively worsening or becoming significantly more intense.
Signs of potential nerve involvement or spinal issues necessitate an urgent visit to a healthcare provider. Traumatic events, such as a fall, sports injury, or car accident, should always be immediately assessed by a physician. Concerning symptoms requiring medical attention include:
- Numbness or tingling sensations radiating down the arms or hands
- Significant muscle weakness in the limbs or a sudden loss of coordination
- Pain accompanied by fever or chills
- Unexplained weight loss, difficulty swallowing, or changes in vision or balance