title: Spontaneous fracture of the odontoid process in rheumatoid arthritis.
abstract: Six cases of spontaneous fracture of the odontoid process in rheumatoid arthritis are presented. Fifty-one patients with atlantoaxial subluxation in rheumatoid arthritis underwent surgery between 1981 and 1990. This included six patients (in 10%) who had subluxation accompanied by fracture of the odontoid without apparent trauma. The mean patient age was 58 years and all had a long history of rheumatoid arthritis. No trauma was considered to be the cause of the fracture. This is a fracture caused by erosion and osteoporosis of the odontoid process due to rheumatoid synovitis, aging and steroid therapy. In addition, another cause is a dynamic load produced from the instability accompanying atlantoaxial subluxation working on the odontoid in cervical extension. It is important remember that the odontoid process is susceptible to spontaneous fracture.
authors.affiliation: Department of Orthopaedic Surgery, School of Medicine, Keio University, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Toyama
authors.forename: K
authors.initials: K
authors.lastname: Hirabayashi
authors.forename: Y
authors.initials: Y
authors.lastname: Fujimura
authors.forename: K
authors.initials: K
authors.lastname: Satomi
mesh_terms: D000368:Aged; D001172:Arthritis, Rheumatoid / Q000150:complications*; D001268:Atlanto-Axial Joint / Q000293:injuries; D005260:Female; D005598:Fractures, Spontaneous / Q000000981:diagnostic imaging / Q000209:etiology* / Q000601:surgery; D006801:Humans; D004204:Joint Dislocations / Q000209:etiology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009809:Odontoid Process / Q000293:injuries*; D011859:Radiography; D016103:Spinal Fractures / Q000000981:diagnostic imaging / Q000209:etiology* / Q000601:surgery