Health Topic

Chiari Malformation

Chiari Malformation (CMs) is a congenital condition in which brain tissue extends to the spinal canal. Learn about the different types and symptoms.

Reviewed Reviewed by a registered pharmacistGeneral information

Also called: Arnold-Chiari Malformation

Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.

About Chiari Malformation

Chiari malformations (CMs) are structural defects in the cerebellum. The cerebellum is the part of the brain that controls balance. With CM, brain tissue extends into the spinal canal. It can happen when part of the skull is too small, which pushes the brain tissue down. There are several types of CM. One type often happens in children who have neural tube defects. Some types cause no symptoms and don't need treatment. If you have symptoms, they may include:

  • Neck pain
  • Balance problems
  • Numbness or other abnormal feelings in the arms or legs
  • Dizziness
  • Vision problems
  • Difficulty swallowing
  • Poor hand coordination

Doctors diagnose CM using imaging tests. Medicines may ease some symptoms, such as pain. Surgery is the only treatment available to correct or stop the progression of nerve damage.

It sits within Brain and Nerves and Genetics/Birth Defects.

The lead U.S. institute for this subject is the National Institute of Neurological Disorders and Stroke.

When to speak to someone. Reading about a topic cannot tell you whether it applies to you. Speak to a doctor or pharmacist if symptoms are severe, sudden, getting worse, or simply not going away — and seek emergency care immediately for chest pain, breathing difficulty, sudden weakness or confusion, or a serious allergic reaction.

Research on Chiari Malformation

35 studies areregistered for this condition on ClinicalTrials.gov, the U.S. National Library of Medicine's public registry. A selection is below — the links go straight to the registry entry, not to a summary of ours.

What a registered study does and does not mean. Registration means a study exists and has been declared publicly. It says nothing about whether the treatment being tested works, is safe, or is available to you. Many studies find no benefit — that is what research is for. Never seek out an experimental treatment on the strength of a registry entry alone.

Research currently under way

Research already completed

Study data from ClinicalTrials.gov, a service of the U.S. National Library of Medicine. Retrieved 2026-07-30. Registry entries are supplied by study sponsors and investigators; ClinicalTrials.gov does not verify their scientific validity. PocketsInfo is not affiliated with, and not endorsed by, the NLM or the NIH.

Where to read more

Rather than paraphrase, we point you to the primary sources. Every link below is to a government health agency, a national institute or a recognised medical body — grouped by what you are trying to find out.

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Clinical Trials

Medical subject headings

Clinicians and researchers index this subject under Arnold-Chiari Malformation. These are the terms to use when searching medical literature.

This page is built from the MedlinePlus health topic record for Chiari Malformation, a service of the U.S. National Library of Medicine (NLM), National Institutes of Health. Information is from MedlinePlus.gov. PocketsInfo is not affiliated with, and is not endorsed by, the NLM or the NIH. Retrieved 30 July 2026.