dystonia

dystonia
—dystonic /dis ton"ik/, adj.
/dis toh"nee euh/, n. Pathol.
abnormal tone of any tissue.
[DYS- + -TONIA]

* * *

      movement disorder characterized by the involuntary and repetitive contraction of muscle groups, resulting in twisting movements, unusual postures, and possible tremor of the involved muscles. As the disorder persists, movement may affect other muscle groups. Although dystonias may occur in families or sporadically, many are secondary to other disorders as reactions to medications; for example, one of the most common dystonias is induced by levodopa, a drug used in the treatment of Parkinson disease (parkinsonism).

      Dystonias may be classified in several ways, one of which is the mode of initiation of the movement; often the dystonia appears only with a specific action, such as the contraction of hand muscles when writing is attempted (writer's cramp). Another means of classification is the extent of muscle involvement: focal, affecting only one muscle group, such as the vocal cords (e.g., spastic dysphonia); segmental, involving two adjacent muscle groups, such as the neck muscles (e.g., spastic torticollis); or general, affecting the entire body.

      Treatment (therapeutics) varies depending on the cause. In some cases, dystonia may be treated by discontinuing use of the drug that is causing the symptoms. Various medications that act on different parts of the nervous system are often effective in the treatment of dystonias. Surgical therapies also may be used, such as thalamotomy, a procedure that destroys a specific group of cells in the brain, or cutting the nerves that supply the dystonic area. Some dystonias can be treated with botulinum toxin (e.g., Botox™, Myobloc™, and NeuroBloc™). An injection of this potent blocker of nerve transmission produces a temporary chemical denervation of the muscles that may last for several months.

Robert Joynt
 

* * *


Universalium. 2010.

Игры ⚽ Поможем сделать НИР

Look at other dictionaries:

  • dystonia — [dis tō′ne ə] n. a lack of normal muscle tone due to disease or infection of the nervous system dystonic [distän′ik] adj …   English World dictionary

  • Dystonia — Dystonias Classification and external resources A person with medication induced dystonia. ICD 10 G24.9 …   Wikipedia

  • Dystonia — Involuntary movements and prolonged muscle contraction, resulting in twisting body motions, tremor, and abnormal posture. These movements may involve the entire body, or only an isolated area. Symptoms may even be "task specific," such… …   Medical dictionary

  • dystonia — n. muscle dysfunction characterized by spasms or abnormal muscle contraction. One form is a postural disorder often associated with disease of the basal ganglia in the brain. There may be spasm in the muscles of the face (see hemifacial spasm),… …   The new mediacal dictionary

  • dystonia musculorum deformans — dystonia mus·cu·lo·rum de·for·mans .məs kyə lȯr əm di fȯr .manz n a rare inherited neurological disorder characterized by progressive muscular spasticity causing severe involuntary contortions esp. of the trunk and limbs called also torsion… …   Medical dictionary

  • dystonia lenticularis — dystonia due to a lesion of the lenticular nucleus …   Medical dictionary

  • Dystonia, cranial — A term used to describe dystonia that affects the muscles of the head, face, and neck. Oromandibular dystonia affects the muscles of the jaw, lips, and tongue. The jaw may be pulled either open or shut, and speech and swallowing can be difficult …   Medical dictionary

  • Dystonia, torsion — A form of dystonia known as early onset torsion dystonia (also called idiopathic or generalized torsion dystonia) begins in childhood around the age of 12. Symptoms typically start in one part of the body, usually in an arm or leg, and eventually …   Medical dictionary

  • Dystonia, idiopathic torsion — A form of dystonia known as early onset torsion dystonia (also called generalized torsion dystonia) begins in childhood around the age of 12. Symptoms typically start in one part of the body, usually in an arm or leg, and eventually spread to the …   Medical dictionary

  • Dystonia, dopa-responsive (DRD) — A condition that typically begins in childhood or adolescence with progressive difficulty in walking and, in some cases, spasticity and can be successfully treated with drugs. Segawa dystonia is an important variant of DRD. In Segawa dystonia,… …   Medical dictionary

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”