Dystonia
DEFINITION
In dystonia, your muscles contract involuntarily — causing uncontrollable repetitive or twisting movements of the affected body part. Your symptoms may be mild or severe, and may interfere with your performance of many day-to-day tasks.
Doctors divide dystonia into categories including generalized, focal, segmental and other less common categories. In focal dystonia, the most common category, one part of your body is affected. Generalized dystonia affects most or all of your body. In segmental dystonia, two or more adjacent areas of your body are affected. Some types of dystonia are inherited.
Medications can sometimes improve dystonia symptoms, but inconsistently. In some more-severe cases, surgery may be used to disable or regulate certain brain regions or nerves.
CAUSES
Doctors don’t know exactly what causes most cases of dystonia, but a few factors may be involved.
Altered nerve cell communication
Dystonia may be linked to altered communication between nerve cells located in the basal ganglia — an area of the brain involved in initiating muscle contractions.
Genetic changes
Dystonia sometimes may be inherited. Researchers also have discovered many genetic changes associated with some inherited forms of dystonia.
Other disorders
Sometimes dystonia may be a symptom of another disorder or condition, including:
- Parkinson’s disease
- Huntington’s disease
- Wilson’s disease
- Traumatic brain injury
- Birth injury
- Stroke
- Brain tumor
- Paraneoplastic syndromes
- Oxygen deprivation
- Infections, such as tuberculosis or encephalitis
- Reactions to certain medications
- Heavy metal or carbon monoxide poisoning
SYMPTOMS
Dystonia symptoms:
- Include involuntary muscle contractions that cause repetitive movements or distorted postures
- Begin in a single area, such as your foot, hand or neck
- May occur during a specific action, such as handwriting
- May worsen with stress, fatigue or anxiety
- May become more noticeable over time
The impact of dystonia on your quality of life varies depending on the part of your body affected, the type of dystonia and the severity of your muscle contractions. Areas of the body affected may include:
- Eyelids. Rapid blinking or involuntary spasms causing your eyes to close (blepharospasm) can make you functionally blind.
- Neck. In cervical dystonia, contractions cause your head to twist and turn to one side, or pull forward or backward, sometimes causing pain.
- Face, head and neck. In craniofacial dystonia, your face, head or neck muscles are affected by contractions. Oromandibular dystonia affects your jaw movement or tongue and may cause slurred speech or difficulty swallowing.
- Vocal cords. Some forms of dystonia affect muscles that control your vocal cords (spasmodic dysphonia), causing a tight or whispering voice.
- Hand and forearm. Some types of dystonia only occur while you’re conducting a repetitive activity. In musician’s dystonia, your ability to play a specific instrument may be impaired. In writer’s cramp, your hand and forearm muscles are affected while you’re writing. Dystonia also may occur during other specific tasks.
When to see a doctor
Because early symptoms of dystonia often are mild, intermittent and linked to a specific activity, some people with dystonia may initially think they’re just imagining a problem. If you or someone you know is experiencing involuntary muscle contractions, a doctor visit may lead to helpful treatment.
