Dystonias

[Dave Paprocki]

Dystonias are sustained involuntary muscle contractions of antagonistic muscle groups in the same body part, leading to sustained abnormal posturing or jerky, twisting, intermittent spasms that can resemble tremors, athetosis, or choreoathetosis. Dystonias can be primary or secondary and can be generalized, focal, or segmental. Diagnosis is clinical. Botulinum toxin injections are used to treat focal or segmental dystonias. Treatment of severe generalized dystonia may require a combination of oral anticholinergic drugs, muscle relaxants, and benzodiazepines. Severe segmental or generalized dystonia that is refractory to treatment may require surgery.
(See also Overview of Movement and Cerebellar Disorders.)
Dystonia may be

Primary (idiopathic)
Secondary to central nervous system (CNS) disorders or drugs

CNS disorders that can cause dystonias include

Wilson disease
Pantothenate kinase‒associated neurodegeneration [PKAN] associated with PANK2 mutations [previously, Hallervorden-Spatz disease]
Various lipidoses
Multiple sclerosis
Cerebral palsy
Stroke
Brain hypoxia

Drugs that most commonly cause dystonias include

Antipsychotics (eg, phenothiazines, thioxanthenes, butyrophenones)
Antiemetics (eg, metoclopramide , prochlorperazine )

Dystonia may resemble athetosis and choreoathetosis and should be distinguished from them because etiology and management may differ.

[Little_Girl]

a movement disorder in which the head or an arm or leg is put into an unnatural position: