title: Upward migration of the odontoid peg in rheumatoid arthritis.
mesh_terms: D000328:Adult; D001172:Arthritis, Rheumatoid / Q000150:complications* / Q000000981:diagnostic imaging / Q000601:surgery; D001368:Axis, Cervical Vertebra / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D011859:Radiography; D013122:Spinal Diseases / Q000150:complications; D013123:Spinal Fusion