Cervical spine involvement in rheumatoid arthritis.

Cervical spine involvement in rheumatoid patients is common, the clinical symptoms varying from the asymptomatic state to severe occipito-cervical pain and various neurological syndromes. Atlanto-axial subluxation is the most common deformity and it should be operated on if it causes medullary compression signs or severe occipito-cervical headache and has an instability amplitude greater than 9 mm. Experience based on 155 cases of operatively treated rheumatoid cervical spine instabilities and deformities is described and discussed.