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Coordination Disorders


Alex Rajput

, MD, University of Saskatchewan;

Eric Noyes

, MD, University of Saskatchewan

Reviewed/Revised Feb 2024
Topic Resources

Coordination disorders often result from malfunction of the cerebellum, the part of the brain that coordinates voluntary movements and controls balance.

  • The cerebellum malfunctions, causing loss of coordination.

  • Often, people cannot control their arms and legs, making them take wide, unsteady steps when they walk.

  • Doctors base the diagnosis on symptoms, family history, magnetic resonance imaging of the brain, and often genetic testing.

  • The cause is corrected if possible, and if it cannot be, treatment focuses on relieving symptoms.

The cerebellum is the part of the brain most involved in coordinating sequences of movements. It also controls balance and posture. Anything that damages the cerebellum can lead to loss of coordination (ataxia). However, Many other disorders can also cause loss of coordination.

Causes of Coordination Disorders

The leading cause of coordination disorders is

  • Prolonged, excessive alcohol use, which permanently damages the cerebellum

Rarely, in people with cancer (including breast cancer, ovarian cancer, and lung cancer), the immune system malfunctions and attacks the cerebellum—an autoimmune reaction. This disorder, called subacute cerebellar degeneration Neurologic syndromes , results in loss of coordination.

In children, brain tumors may be the cause.

Certain medications (such as antiseizure medications Antiseizure medications In seizure disorders, the brain's electrical activity is periodically disturbed, resulting in some degree of temporary brain dysfunction. Many people have unusual sensations just before a seizure... read more ) and other substances, especially when they are taken in high doses, can cause coordination disorders. In such cases, the disorder may disappear when the medication or substance is stopped.

Did You Know...

  • The most common cause of coordination disorders is prolonged, excessive alcohol use.


Symptoms of Coordination Disorders

Loss of coordination prevents people from being able to control the position of their arms and legs or their posture. Thus, when they walk, they take wide steps and stagger and make broad, zigzag movements with their arms when they reach for an object.

Coordination disorders can cause other abnormalities, such as the following:

Muscle tone may decrease.

Friedreich ataxia

Friedreich ataxia is a hereditary disorder. The gene for Friedreich ataxia is recessive. Thus, to develop the disorder, people must inherit two copies of the abnormal gene, one from each parent.

Friedreich ataxia is progressive. Walking becomes unsteady between the ages of 5 and 15. Then arm movements become uncoordinated, and speech becomes slurred and hard to understand.

People with Friedreich ataxia cannot sense vibrations, cannot sense where their arms and legs are (lose their position sense), and no longer have reflexes. Mental function may deteriorate. Tremor, if present, is slight.

Heart problems often develop and become progressively worse.

By their late 20s, people with Friedreich ataxia may be confined to a wheelchair. Death, often due to an abnormal heart rhythm or heart failure, usually occurs by middle age.

Spinocerebellar ataxias

The gene for spinocerebellar ataxias (SCAs) is dominant. Thus, having only one copy of the abnormal gene, inherited from one parent, is sufficient to cause the disorder. There are many different types of these ataxias. Worldwide, SCA type 3 (formerly called Machado-Joseph disease) may be the most common. These disorders are progressive, degenerative, and often eventually fatal. There is no known effective treatment.

Symptoms of SCAs vary by type, but most cause problems with sensation (for example, people feel pain, touch, and vibration less well or not at all), muscle weakness, and restless legs syndrome Periodic Limb Movement Disorder (PLMD) and Restless Legs Syndrome (RLS) Periodic limb movement disorder involves repetitive movements of the arms, legs, or both during sleep. Restless legs syndrome involves an irresistible urge to move and usually abnormal sensations... read more , as well as loss of coordination. People have problems with balance, speech, and eye movements. Some types typically cause only loss of coordination.

SCAs are a common cause of intention tremors (triggered by a purposeful movement). People may have symptoms that resemble those of Parkinson disease (parkinsonism Parkinson Disease (PD) Parkinson disease is a slowly progressive degenerative disorder of specific areas of the brain. It is characterized by tremor when muscles are at rest (resting tremor), increased muscle tone... read more ), such as tremors and stiff muscles.

Some people with SCA type 3 have other symptoms in addition to loss of coordination and tremors. Their eye movements may be impaired, their facial muscles and the tongue may twitch uncontrollably, and their eyes may bulge. Some people have long-lasting (sustained), painful involuntary muscle contractions (dystonia Dystonias Dystonias are involuntary muscle contractions, which may be long-lasting (sustained) or come and go (intermittent). Dystonias may force people into abnormal positions—for example, causing the... read more ).

Diagnosis of Coordination Disorders

  • A doctor's evaluation

  • Usually magnetic resonance imaging

  • Sometimes genetic testing

The diagnosis of coordination disorders is based on symptoms. Doctors also ask about relatives who have had similar symptoms or conditions that could cause the symptoms (family history). Doctors also do a physical examination, including a neurologic examination Neurologic Examination When a neurologic disorder is suspected, doctors usually evaluate all of the body systems during the physical examination, but they focus on the different parts of the nervous system. Examination... read more , to check for conditions that could cause the symptoms in the affected person.

Genetic testing is being increasingly done in people who may have a family history of coordination disorders.

Treatment of Coordination Disorders

  • Treatment of the cause if possible

  • Physical and occupational therapy

If possible, the cause is eliminated or treated. For example, if the coordination disorder is due to use of alcohol, alcohol is stopped. If the disorder is caused by a high dose of a medication (such as phenytoin), the dose is reduced. Some underlying disorders, such as hypothyroidism Hypothyroidism Hypothyroidism is underactivity of the thyroid gland that leads to inadequate production of thyroid hormones and a slowing of vital body functions. Facial expressions become dull, the voice... read more Hypothyroidism and vitamin E deficiency Vitamin E Deficiency Vitamin E deficiency caused by a diet low in vitamin E is common in countries with high rates of food insecurity. In countries with low rates of food insecurity, the cause is usually an absorption... read more , can be treated. Surgery may help some people with brain tumors.

There is no cure for hereditary coordination disorders. In such cases, treatment focuses on relieving symptoms. Riluzole may help improve coordination in the short term.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Alph-E-Mixed , AQUA-E, Aquasol E , Aquavite-E
Dilantin, Dilantin Infatabs, Dilantin-125, Phenytek
Exservan, Rilutek, TEGLUTIK, Tiglutik
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