Dystonia is a movement disorder in which your muscles contract involuntarily, causing repetitive or twisting movements.
The condition can affect one part of your body (focal dystonia), two or more adjacent parts (segmental dystonia) or all parts of your body (general dystonia). The muscle spasms can be mild or severe, and might interfere with your performance of day-to-day tasks.
There's no cure for dystonia. But medications can improve symptoms. Surgery is sometimes used to disable or regulate nerves or certain brain regions in people with severe dystonia.
Dystonia affects different people in varying ways. Muscle contractions might:
- Begin in a single area, such as your leg, neck or arm. Focal dystonia that begins after age 21 usually starts in the neck, arm or face and tends to remain focal or segmental.
- Occur during a specific action, such as handwriting.
- Worsen with stress, fatigue or anxiety.
- Become more noticeable over time.
Areas of the body that can be affected include:
- Neck (cervical dystonia). Contractions cause your head to twist and turn to one side, or pull forward or backward, sometimes causing pain.
- Eyelids. Rapid blinking or involuntary spasms causing your eyes to close (blepharospasms) can make you functionally blind. Spasms usually aren't painful, but might increase when you're in bright light, under stress or interacting with people. Your eyes might feel dry.
- Jaw or tongue (oromandibular dystonia). You might experience slurred speech, drooling, and difficulty chewing or swallowing. Oromandibular dystonia can be painful and often occurs in combination with cervical dystonia or blepharospasms.
- Voice box and vocal cords (spasmodic dystonia). You might have a tight or whispering voice.
- Hand and forearm. Some types of dystonia occur only while you do a repetitive activity, such as writing (writer's dystonia) or playing a specific musical instrument (musician's dystonia).
When to see a doctor
Early signs of dystonia often are mild, occasional and linked to a specific activity. See your doctor if you're experiencing involuntary muscle contractions.
The exact cause of dystonia isn't known. But it might involve altered nerve-cell communication in several regions of the brain. Some forms of dystonia are inherited.
Dystonia also can be a symptom of another disease or condition, including:
- Parkinson's disease
- Huntington's disease
- Wilson's disease
- Traumatic brain injury
- Birth injury
- Brain tumor or certain disorders that develop in some people with cancer (paraneoplastic syndromes)
- Oxygen deprivation or carbon monoxide poisoning
- Infections, such as tuberculosis or encephalitis
- Reactions to certain medications or heavy metal poisoning
Depending on the type of dystonia, complications can include:
- Physical disabilities that affect your performance of daily activities or specific tasks
- Functional blindness from dystonia that affects your eyelids
- Difficulty with jaw movement, swallowing or speech
- Pain and fatigue, due to constant contraction of your muscles
- Depression, anxiety and social withdrawal