Disruptions in other portions of the basal ganglia are thought to cause tics, tremors, dystonia, and a variety of other movement disorders, although the exact mechanisms are not well understood.
It may be associated with involuntary muscle spasms, sustained muscle contractions (dystonia), and exaggerated deep tendon reflexes that make movement difficult or uncontrollable.
Botulinum-toxin type A (Botox, Dysport) or type B (Myobloc) is injected locally into the affected muscle group to relax the muscles in dystonia or spasticity.
Some diseases that cause sustained muscle contraction limited to a particular muscle group (focal dystonia) are inherited, but others are caused by trauma.
Botox is commonly used for cosmetic treatment of wrinkles but is also used to treat neuromuscular problems, including migraine and cervical dystonia.
The drug can also help with dystonia, a severe contraction of muscles in the shoulder and neck.
Dystonia may be limited to one area (focal) or may affect the whole body (general).
Dystonia may be painful as well as incapacitating.