title: Atlantoaxial instability and acquired basilar invagination in rheumatoid arthritis.
mesh_terms: D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000000981:diagnostic imaging / Q000473:pathology*; D001368:Axis, Cervical Vertebra / Q000000981:diagnostic imaging / Q000473:pathology*; D001270:Cervical Atlas / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010985:Platybasia / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology; D011859:Radiography; D013122:Spinal Diseases / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology