Dystonia is a movement disorder that causes involuntary muscle contractions and spasms. Opposing muscles often contract at once, forcing the affected body part into repetitive and even violently twisting movements or awkward, irregular postures that may be uncomfortable and painful.
Dystonia is classified by the type of muscles that are affected such as:
- Spasmodic Torticollis (neck)
- Blepharospasm (eyelids)
- Spasmodic Dysphonia (voice)
- Meige Syndrome (jaw)
- Generalized Dystonia—usually hereditary
Dystonias may also be classified by the part of the body affected:
- Generalized—entire body
- Hemibody—one side
- Focal—one body part
A body part affected by dystonia is commonly also affected by tremor. This is called dystonic tremor.
Some patients with dystonia use a sensory trick to overcome or break dystonic movements. This is referred to as Gestes antagonists, and it involves the patient touching the body part that is affected by the dystonia. For example, a patient with torticollis may temporarily break the neck spasm by placing his hand on his cheek.
In some patients, dystonia is the source of the movement disorder.
Incidence of Dystonia
- An estimated 300,000 people in North America are affected by dystonia.
Symptoms of Dystonia
- Involuntary muscle contractions
- Involuntary twisting movements
Symptoms may differ significantly from patient to patient, depending on the region of the body affected and the severity of the condition.