Dystonia is a neurological movement disorder in which the muscles contract involuntarily, causing twisting and repetitive movements of the affected body parts or abnormal posture. The involuntary movements can affect one or many muscle groups, usually starting in the hand, foot, or neck. Symptoms can range from mild to severe, and can impair daily activities. Dystonia occurs in children as well as in adults, and affects males and females in equal numbers.
Dystonia originates in the parts of the brain concerned with motor function, such as the basal ganglia and the Purkinje neurons (located in the cerebellum) that produce GABA (gamma-aminobutyric acid).
Dystonia can develop on its own (called primary dystonia) or be a symptom of another condition (called secondary dystonia), such as Parkinson’s disease, traumatic brain injury, infection, stroke, and other disorders.
Primary dystonia is brought on by a problem with the central nervous system, originating in certain parts of the brain that control motor skills, such as the basal ganglia. It is thought that genetic predisposition plays a part in primary dystonia.
Secondary dystonia refers to dystonia that is thought to be caused by an outside factor, such as environmental toxins, brain trauma, reaction to certain drugs, or diseases of the central nervous system. Focal dystonia is thought be related to specific and repetitive tasks, such as the high-precision movements of musicians, artists and engineers.
Dystonia can also be generalized (affecting the whole body), or focal (affecting only a portion of the body). Generalized dystonia is more common in children than in adults.
Primary dystonia usually occurs in children and young adults, where it is also called early- or childhood-onset dystonia. When dystonia is a component of Parkinson’s disease, it usually occurs in those over 30 years old and is called late- or adult-onset.
What Causes Dystonia?
While the causes of dystonia are not fully understood, there are specific and effective treatments. Individuals suspected or diagnosed as having dystonia should be evaluated at a major medical center with a multidisciplinary Movement Disorders service to ensure accurate diagnosis and state-of-the-art treatment. Children should be treated by experts at a specialized Pediatric NeuroMotor Disorders Program.
Reviewed by Michael Kaplitt, M.D., Ph.D.
Last reviewed/last updated: April 2022