Extraforaminal Vertebral Artery Until C2 Transverse Foramen in Down Syndrome Patient Affected by Atlantoaxial Subluxation: First Observation and Review of Literature.

Background: Patients with Down syndrome (DS) have an increased incidence of multisystem disorders, like cardiovascular, neurologic, gastrointestinal, respiratory, and musculoskeletal disorders. Craniovertebral junction instability is a common illness in DS patients, and they may often be affected by vertebral artery (VA) anomalies.

Case Description: In this paper we present neuroradiologic findings of a 34-year-old female patient affected by DS with atlantoaxial subluxation, scheduled for transoral decompression of C1-C2 and posterior occipitocervical fixation.