Anteroposterior atlantoaxial subluxation in cervical spine osteoarthritis:Case reports and review of the literature

Nontraumatic anteroposterior atlantoaxial subluxation (AAS) has been descri bed in several rheumatic or inherited disorders, especially rheumatoid arth ritis and to a lesser extent the inflammatory spondyloarthropathies. We des cribe AAS secondary to osteoarthritis (OA) of the cervical spine in a 76-ye ar-old man and a 73-year-old woman with severe cervical OA, symptomatic C1- C2 facet joints, and signs of generalized OA. Only 6 similar cases exist in the literature. OA should be added to the causes of AAS, and conversely AA S should be assessed in cases with severe OA of the upper cervical spine.