Dystonia
From Holoprosencephaly
What are the dystonias?
The dystonias are movement disorders in which sustained muscle contractions cause twisting and repetitive movements or abnormal postures. The movements, which are involuntary and sometimes painful, may affect a single muscle; a group of muscles such as those in the arms, legs, or neck; or the entire body.
What are the symptoms?
Dystonia can affect many different parts of the body. Early symptoms may include foot cramps, and/or a tendency of one foot to pull up or drag; this may occur "out of the blue" or may occur after running or walking some distance. The neck may turn or pull involuntarily, especially when the patient is tired or stressed. Sometimes both eyes will blink rapidly and uncontrollably, rendering a person functionally blind. Other possible symptoms are tremor and voice or speech difficulties. The initial symptoms can be very mild and may be noticeable only after prolonged exertion, stress, or fatigue. Over a period of time, the symptoms may become more noticeable and widespread and be unrelenting; sometimes, however, there is little or no progression.
How are the dystonias classified?
One way to classify the dystonias is according to the parts of the body they affect:
Generalized dystonia affects most or all of the body. Focal dystonia is localized to a specific part of the body. Multifocal dystonia involves two or more unrelated body parts. Segmental dystonia affects two or more adjacent parts of the body. Hemidystonia involves the arm and leg on the same side of the body.
Are there any treatments?
No one treatment has been found universally effective. Instead, physicians use a variety of therapies aimed at reducing or eliminating muscle spasms and pain.
Medication. Several classes of drugs that may help correct imbalances in neurotransmitters have been found useful. But response to drugs varies among patients and even in the same person over time. The most effective therapy is often individualized, with physicians prescribing several types of drugs at different doses to treat symptoms and produce the fewest side effects.
Frequently, the first drug administered belongs to a group that reduces the level of the neurotransmitter acetylcholine. Drugs in this group include trihexyphenidyl, benztropine, and procyclidine HCl. Sometimes these medications can be sedating, especially at higher doses, and this can limit their usefulness.
Drugs that regulate the neurotransmitter GABA may be used in combination with these drugs or alone in patients with mild symptoms. GABA-regulating drugs include the muscle relaxants diazepam, lorazepam, clonazepam, and baclofen.
Anticonvulsants including carbamazepine, usually prescribed to control epilepsy, have occasionally helped individuals with dystonia.
Botulinum toxin. Minute amounts of this familiar toxin can be injected into affected muscles to provide temporary relief of focal dystonias. First used to treat blepharospasm, such injections have gained wider acceptance among physicians for treating other focal dystonias. The toxin stops muscle spasms by blocking release of the excitatory neurotransmitter acetylcholine. The effect lasts for up to several months before the injections have to be repeated.
Surgery may be recommended for some patients when medication is unsuccessful or the side effects are too severe. Surgically cutting or removing the nerves to the affected muscles has helped some focal dystonias, including blepharospasm, spasmodic dysphonia and torticollis. The benefits of these operations, however, can be short-lived. They also carry the risk of disfigurement, can be unpredictable, and are irreversible.
What is the prognosis?
The initial symptoms can be very mild and may be noticeable only after prolonged exertion, stress, or fatigue. Dystonias often progress through various stages. Initially, dystonic movements are intermittent and appear only during voluntary movements or stress. Later, individuals may show dystonic postures and movements while walking and ultimately even while they are relaxed. Dystonic motions may lead to permanent physical deformities by causing tendons to shorten.
To learn more about movement problems and treatment options in children with Holoprosencephaly, also see:
[Do all children with HPE have movement problems?]
[How will I know if my child has Dystonia?]
You may also find this external link beneficial:Brain Connection
It describes what areas of the brain control muscle tone and movement.
Source: http://www.ninds.nih.gov/disorders/dystonias/dystonias.htm
