Copyright 1993 by the National Ataxia Foundation, Inc.
All rights reserved.
ATAXIA
What is ataxia?
Ataxia is a symptom, not a specific disease or diagnosis. Ataxia
means clumsiness, or loss of coordination. Ataxia may affect the
fingers and hands, the arms or legs, the body, speech or eye
movements. This loss of coordination may be caused by a number
of different medical or neurologic conditions; for this reason,
it is important that a person with ataxia seek medical attention
to determine the underlying cause of the symptom and to get the
appropriate treatment.
What causes ataxia?
Most often, ataxia is caused by loss of function in the part of
the brain which serves as the "coordination center", which is the
cerebellum. The cerebellum is located toward the back and lower
part of the head. The right side of the cerebellum controls
coordination on the right side of the body, and the left side
controls coordination on the left. The central part of the
cerebellum is involved in coordinating the very complex movements
of gait, or walking. Other parts of the cerebellum help to
coordinate eye movements, speech and swallowing.
Ataxia may also be caused by dysfunction of the pathways leading
into and out of the cerebellum. Information comes into the
cerebellum from the spinal cord and other parts of the brain, and
signals from the cerebellum go out to the spinal cord and to the
brain. Although the cerebellum does not directly control
strength ("motor function") or feeling ("sensory function"), the
motor and sensory pathways must work properly to provide the
correct input into the cerebellum. Thus, a person with impaired
strength or sensation may notice clumsiness or poor coordination,
and the doctor may say that person has ataxia.
How does a physician diagnose ataxia?
Remember, ataxia is a symptom, not a diagnosis. If you have
clumsiness or loss of coordination in an arm or both legs or
slurred speech, the physician may say that you have an ataxic arm
or ataxic gait or ataxic speech. Then the physician must
determine why this has happened. To do this, the physician will
first ask many questions about your ataxia, how it came on,
whether it is getting worse, whether there are any other
symptoms, and so on.
A very important part of the evaluation is the neurologic
examination. The physician can usually determine whether the
ataxia is caused by trouble in the cerebellum, its associated
pathways, or other parts of the nervous system by his neurologic
examination. A careful neurologic and general physical
examination can also determine whether other parts of the nervous
system are impaired and whether a medical illness may be causing
the ataxia.
Blood tests and X-rays may be very helpful in the diagnosing
specific medical or neurologic conditions that can cause ataxia,
or in "ruling out" suspected causes.
Here is a list of some medical and neurologic conditions that can
cause ataxia to appear suddenly:
* head trauma
* stroke
* brain hemorrhage
* brain tumor
* congenital abnormality (the back part of
the brain was formed in an unusual way)
* "post-infectious" (after a severe viral
infection
* exposure to certain drugs or toxins
(e.g. alcohol, seizure medicine)
* following cardiac or respiratory arrest
Here is a list of some medical and neurologic conditions that can
cause ataxia to appear gradually:
* hypothyroidism
* deficiencies of certain vitamins
(e.g. Vitamin E, Vitamin B12)
* exposure to certain drugs or toxins (e.g.
heavy metals, seizure medicine, chronic
alcohol exposure, certain cancer drugs)
* related to certain kinds of cancer (e.g.
ovarian, lung cancer)
* congenital abnormality (the back part of
the brain was formed in an unusual way)
* multiple sclerosis
* syphilis (locomotor ataxia)
* hereditary disorders
* "idiopathic" (unknown cause) cerebellar degeneration
disorders
You can see that the list of conditions that the physician must
think about as causes of ataxia is rather long; proper diagnosis
may require a number of examinations, X-rays, and tests.
How is ataxia treated?
There is no medicine which specifically treats the symptoms of
ataxia. If ataxia is due to a stroke, a low vitamin level, or
exposure to a toxic drug or chemical, then treatment would
include treatment of the stroke, vitamin therapy, or avoiding the
toxic drug or chemical. There is no reason to think that taking
vitamins or thyroid will help ataxia that is not caused by
vitamin or thyroid deficiency.
The treatment of incoordination or ataxia, then, mostly involves
the use of adaptive devices to allow the ataxic individual to
maintain as much independence as possible. Such devices may
include a cane, crutches, walker, or wheelchair for those with
impaired gait; devices to assist with writing, feeding, and self
cares if hand and arm coordination is impaired; and communication
devices for those with impaired speech.
Many patients with hereditary or idiopathic forms of ataxia have
symptoms in addition to ataxia. Medication or other therapies
might be appropriate for some of these symptoms, which could
include tremor, stiffness, depression, spasticity, and sleep
disorders, among others.
How can the National Ataxia Foundation help?
Although the National Ataxia Foundation is interested in all
forms of ataxia, its major focus is on the hereditary and
idiopathic ataxias. While the treatment and prognosis of ataxia
due to other causes such as stroke or tumor depends primarily on
the treatment of the underlying cause, for the hereditary and
idiopathic ataxias, little is understood of the underlying cause
and no definitive treatment is available.
The National Ataxia Foundation is committed to education about
ataxia, service to individuals afflicted with the various forms
of ataxia, and promoting research to find the causes, better
treatments, or a cure for ataxia. NAF can help by providing
information for you, your family, and your physician about
ataxia.
If you have additional questions or if we can be of any
assistance, please contact:
NATIONAL ATAXIA FOUNDATION
750 Twelve Oaks Center
15500 Wayzata Blvd.
Wayzata, MN 55391
(612) 473-7666
FAX: (612) 473-9289
Email: naf@mr.net