Dystonia is a Frequently
By James Gaffney, M.D.
Dystonia is a neurologic movement disorder
characterized by involuntary, sustained, patterned, repetitive muscle
contractions, usually of opposing muscles. These contractions, which typically
affect the same group of muscles in any given individual, cause unwanted
movements or abnormal postures. A person with cervical dystonia
or spasmodic torticollis, for example, might
experience repeated turning or tilting of the head to one side due to
involuntary contractions of the neck muscles. These uncontrollable muscle
spasms can result in considerable pain, as well as difficulty maintaining head
position. The current thinking about dystonia is that
it is not a disease of the muscle, spinal cord, or
nerve roots, but rather a primary brain disease having to do with processing
movement and motor control.
Approximately 30 people in 100,000 suffer from some form of dystonia in this country, making it a relatively uncommon
condition. Dystonia is often misdiagnosed, as
exemplified by the fact that the average time to diagnosis from onset of
symptoms is measured in years. This is partly because dystonia
is not well known and also because there is no specific test for dystonia, further complicating diagnosis. While there is no
cure, there are therapies available that can reduce symptoms.
Are there different types of dystonia?
A common way to classify dystonia is by the cause,
which is either primary or secondary. Primary dystonia,
which can occur in children and adults, has no known identifiable cause. By
comparison, the onset of secondary dystonia is
related to an identifiable condition such as brain injury, stroke, Parkinson's
disease, multiple sclerosis, or in response to a toxin exposure or to adverse
effects of a medication.
Another way in which dystonia is classified is by
clinical characteristics. When the entire body is affected, this is generalized
dystonia. When a specific region of the body is
affected, this is focal dystonia. There are several
types of focal dystonias. Spasmodic torticollis affects muscles in the head and neck. Cranial dystonia involves the face and jaw; one genetic form is Meige syndrome. Blepharospasm
refers to involuntary contractions of the eyelids, which in severe cases can
result in functional blindness. Laryngeal or spasmodic dysphonia
affects the vocal cords, and may reduce the voice to a breathy whisper. Some
forms of dystonia are brought out by specific
movements or actions (task-specific or action dystonia).
The classic example is writer's cramp, in which involuntary cramping of hand
muscles occurs with handwriting. Professional musicians who develop this type
of dystonia while playing their instrument may find
their playing careers at a premature end.
How is dystonia diagnosed?
Dystonia is diagnosed by a thorough physical and neurologlc examination, and an analysis of the patient's
symptoms. There is no specific test for most forms of dystonia.
Some tests may be necessary to look for underlying medical or neurological
conditions. In fluctuating or episodic conditions, serial evaluations over time
might be needed before the diagnosis is established.
Who is at risk for dystonia?
For the most part, dystonia is an equal
opportunity illness, affecting all races and both genders. Ashkenazi Jews are
at much higher risk for generalized dystonia that the
rest of the population. Meige syndrome is an
inherited dystonia seen in all races. When including
secondary dystonias, it is clear that anyone could
suffer an injury or illness leading to a dystonic
How is it treated?
There are several approaches to treating dystonia
including medication, nonpharmacologic therapies,
surgery, and botulism toxin therapy. For many types of dystonia,
medications are helpful but for many patients they are, at best, partially
effective. For most patients, the most effective therapy is botox
injections. Pharmaceutically manufactured botulinum
toxin is injected into the affected muscles. The effect of the injections is to
decrease the tendency of the overactive muscles to contract by altering the
signal from the nerve to the muscle. The effect wears off in two to six months,
depending on the individual patient. Sometimes unwanted muscle weakness is
produced but this also wears off over time. Surgery is an option for a few of
the focal dystonias. For example, in hemifacial spasm, a neurosurgeon can surgically decompress
the facial nerve. Stretching, exercise or other nonpharmacologic
approaches may be beneficial.
It is also important to recognize the tremendous emotional strain of living
with dystonia. Years of undiagnosed symptoms,
variable degrees of physical pain, and social
ostracism are among a few of the burdens involved. There is no cure for dystonia, but with proper diagnosis, education,
psychological support, and judicious medical management, we can help patients
live with this under-recognized disorder.
Dr. Gaffney is board certified in neurology and serves on the medical
staff of Cayuga Medical
Center at Ithaca. He is in practice with Cayuga
Neurologic Services and can be reached at (607) 273-6757.