Basilar Invagination

In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan.


Basilar Invagination (BI) was first described by Ackermann in cretins. Schuller gave the first radioimaging diagnosis which Chamberlain and other radiologists later refined.

BI is an abnormality at the craniovertebral junction, either congenital or degenerative, resulting in the odontoid prolapsing into the already limited space of the foramen magnum. It is commonly associated with conditions such as Chiari malformation, syringomyelia, and Klippel-Feil syndrome. Clinical presentations can range from chronic headaches, limited neck motion, and acute neurologic deterioration. CT and MRI are critical to diagnosing and managing this condition, including operative planning when needed.

Determining the need for operative intervention is controversial in asymptomatic patients, but those at risk of neurologic compromise could require preoperative cervical traction and algorithmic surgical strategies.

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  • Study Guide