Basilar invagination is a rare but serious condition in which the second cervical vertebra migrates upward into the intracranial space, causing pressure on the upper part of the spinal cord and lower brainstem. Basilar invagination can cause significant and life-threatening neurological symptoms (see Symptoms of Basilar Invagination).
Basilar invagination is a craniocervical junction disorder, meaning that it’s located where the head meets the neck. It should be treated at a major medical center, by experts with experience in craniocervical junction disorders (see Doctors Who Treat Basilar Invagination.) At Chiari CARE we evaluate and treat patients with basilar invagination every week.
Basilar invagination can be associated with a number of conditions such as Chiari malformation, osteomalacia, rheumatoid arthritis, Paget's disease, Ehlers-Danlos syndrome, Marfan syndrome, and osteogenesis imperfecta, or degenerative diseases such as rheumatoid arthritis. What these have in common is hypermobility, or too much movement in the upper cervical spine. The instability and misalignment may lead to the compression of vital neurologic structures, including the brainstem or spinal cord.
What Causes Basilar Invagination?
Basilar invagination may be congenital (present since birth), or it may develop as a result of many conditions. Worsening of basilar invagination can be prevented if detected early, and it can be effectively treated through neurosurgical decompression and stabilization.
Reviewed by Jeffrey Greenfield, Ph.D., M.D.
Last reviewed/last updated: April 2021