title: Three-dimensional motion of the upper cervical spine in rheumatoid arthritis.
abstract: Rheumatoid arthritis frequently contributes to instability of the upper cervical spine. Rotational instability of the upper cervical spine was evaluated in rheumatoid arthritis patients using biplanar x-ray photogrammetry. Three-dimensional cervical motion and the instantaneous axis of rotation of the atlas relative to the axis were evaluated in normal and rheumatoid arthritis patients during axial rotation in the horizontal plane. Anterior atlantoaxial subluxation did not increase during axial head rotation in either the atlantoaxial subluxation or the vertical subluxation groups, while the instantaneous axes of rotation were distributed posteriorly in the dens in the RA-normal group, but were widely scattered in the atlantoaxial subluxation group.
authors.affiliation: Department of Orthopaedic Surgery, School of Medicine, Chiba University, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Iai
authors.forename: S
authors.initials: S
authors.lastname: Goto
authors.forename: M
authors.initials: M
authors.lastname: Yamagata
authors.forename: T
authors.initials: T
authors.lastname: Tamaki
authors.forename: H
authors.initials: H
authors.lastname: Moriya
authors.forename: K
authors.initials: K
authors.lastname: Takahashi
authors.forename: M
authors.initials: M
authors.lastname: Mimura
mesh_terms: D001172:Arthritis, Rheumatoid / Q000000981:diagnostic imaging / Q000503:physiopathology*; D001268:Atlanto-Axial Joint / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D004204:Joint Dislocations / Q000000981:diagnostic imaging / Q000503:physiopathology*; D007593:Joint Instability / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008875:Middle Aged; D009068:Movement / Q000502:physiology; D010780:Photogrammetry / Q000379:methods; D011859:Radiography; D012399:Rotation