Foramen magnum decompression without bone removal: C1–C2 posterior fixation for Chiari with congenital atlantoaxial dislocation/basilar invagination

摘要

Background:Atlantoaxial dislocation (AAD) and basilar invagination (BI) may coexist with Chiari malformations (CM) and a small posterior fossa volume. These are typically treated with craniovertebral junction fusion and foramen magnum decompression (FMD). Here, we evaluated whether C1–C2 posterior reduction and fixation (which possibly opens up the ventral foramen magnum) would effectively treat AAD and CM without additionally performing FMD.