Ataxia is a movement disorder caused by problems in the brain. When you have ataxia, you have trouble moving parts of your body the way you want. Or the muscles in your arms and legs might move when you don’t want them to. The word ataxia actually means “without coordination.”
Ataxia isn’t a disorder or a disease itself -- it’s a sign of other underlying disorders or diseases. Doctors have discovered anywhere from 50 to 100 different ataxias. They are grouped into categories based on what causes them, or based on which part of the body they affect.
Types of Ataxia by Affected Area
Ataxia is caused by damage to different areas of the central nervous system. Doctors categorize it by the specific part of the brain most affected, including:
Your cerebellum is the part of your brain that’s in charge of balance and coordination. If part of your cerebellum starts to wear away, you can develop cerebellar ataxia. Sometimes it can also affect your spinal cord. It’s the most common form of ataxia.
Symptoms of cerebellar ataxia include:
Sensory ataxia is the result of damage to nerves in your spinal cord or your peripheral nervous system. That is the part of your nervous system outside of the brain and spinal cord.
When you have sensory ataxia, you have less sensation in your feet and legs from the nerve damage, so you have less feedback from your brain telling you where your body is in relation to the ground. It’s also called proprioceptive ataxia.
Symptoms of sensory ataxia include:
- Difficulty touching your finger to your nose with closed eyes
- Inability to sense vibrations
- Trouble walking in dim light
- Walking with a “heavy step,” or stomping when you walk
Vestibular ataxia affects your vestibular system. This system is made up of your inner ear and ear canals, which contain fluid. They sense the movements of your head and help with your balance and spatial orientation.
When the nerves in your vestibular system are affected, you can have the following problems:
Causes of Ataxia
Around 150,000 people in the U.S. deal with some form of ataxia. There are different causes for it. Some are genetic, some are acquired, like injuries, and some have no known clear cause.
Genetic. You can inherit a certain mutated, or changed, gene from one or both of your parents that causes ataxia. Or you may inherit a mutated gene that causes a disorder with ataxia as a symptom.
Some of the specific types of genetic ataxia include:
- Ataxia telangiectasia
- Ataxia with oculomotor apraxia
- Dominant spastic ataxias
- Dominant spinocerebellar ataxias (SCA)
- Episodic ataxia
- Friedreich's ataxia
- Recessive spastic ataxias
- Wilson’s disease
Acquired. Acquired ataxia occurs when you have damage to your spinal cord or nerves. The damage might be from an injury or an illness.
Some of the causes of acquired ataxia could include:
Idiopathic. When you haven’t inherited a mutated gene or had an illness or injury that could have caused your ataxia, it’s called idiopathic ataxia. Your doctor will diagnose you with idiopathic ataxia if they can’t find a medical reason for your ataxia symptoms.
The most common idiopathic ataxia is called multiple system atrophy, or MSA. Doctors haven’t pinned down possible causes for this group of ataxias. They may come from a combination of environmental factors and genetic causes.
For some cases, your doctor may recommend tests of your spinal fluid. To do this, they’ll insert a needle into your lower back and draw out the fluid to send it to a lab for testing.
To rule out genetic forms of ataxia, you may need genetic testing. But, not all genetic forms of ataxia have tests to find them.
The best treatment for your ataxia symptoms depends on the type you have. There is no specific treatment for ataxia itself. If your ataxia is a symptom of another disorder, your doctor will treat that disorder.
If it’s due to a cause that you can avoid, like lack of vitamins or exposure to poison, your doctor will help you address the problem causing the ataxia.
In order to help you cope with your symptoms, your doctor may recommend:
Your doctor can also help you find tools so you can move around easier, such as a cane or a walker. There are also utensils to help you eat and speak more easily.