Dystonia

Dystonia is defined as a sustained muscle contraction that forces parts of the body into abnormal and sometimes painful postures.  It may affect a single muscle, a group of muscles, or the entire body.  Dystonia is classified according to the parts of the body affected.

• Generalized dystonia affects several areas of the body on both sides.
• Focal dystonia affects a specific body part.  Types of focal dystonia include blepharospasm (spasm of the eyelid),spasmodic torticollis (spasm of neck muscles), and writer's cramp (spasm of hand muscles).
• Multifocal dystonia involves two or more unrelated body parts.
• Hemidystonia involves the arm and leg on the same side of the body.

Dystonia develops gradually and may begin at any time of life -- childhood, adolescence or adulthood.  It is caused by abnormal functioning of the basal ganglia in the brain.  Primary dystonia, which can be hereditary or sporadic, is dystonia with no other underlying cause such as injury or trauma.  Diagnosis is determined by detailed physical and neurological examinations.

Treatment for dystonia is aimed at decreasing the spasms, pain, and disturbed postures.  Chemical denervation using botulinum toxin is commonly used.  This treatment produces a temporary paralysis of the involved muscles and is most effective when used for focal dystonia.