Background: Chiari malformations (CM) represent a group of anomalies characterized by descent of the cerebellar tonsils or vermis into the cervical spinal canal. These malformations can be associated with abnormalities such as hydrocephalus, spina bifida, hydromyelia, syringomyelia, curvature of the spine (kyphosis and scoliosis) and tethered cord syndrome. Hereditary syndromes and other disorders that affect growth and bone formation—such as craniosynostosis, Ehlers–Danlos syndromes and Klippel–Feil syndrome—can also be associated with CM.
Methods: The literature concerning treatment is large, and an extensive range of therapeutic protocols have been described. The literature is inclined in favour of surgery; however, there is controversy over when to perform surgery and which procedure is most appropriate. Lately, the indications for stabilization have been under discussion.
Results and Conclusion: In this paper we review the literature and discuss the historical background, anatomical forms, pathophysiology, clinical presentation, relationships with other diseases and diagnostic procedures for these abnormalities.
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