title: Carpal instability in rheumatoid wrists.
abstract: This study was conducted to identify patterns of carpal instability in the rheumatoid wrist. One hundred patients with proven rheumatoid arthritis were randomly chosen, and posteroanterior and lateral radiographs of right wrists were taken. The most common isolated pattern was volar intercalated segmental instability, apparent in 16 wrists, while nine wrists had scapholunate dissociations. Larsen grading scores revealed a correlation between disease duration, carpal height ratio, and ulnar translocation index. In the early stages of disease, the scapholunate angle was significantly increased and the lunate rotated volarly due to loosening of the intrinsic carpal ligament. In later phases, the capitolunate angle significantly increased and the capitate rotated dorsally. Patterns of carpal instability in rheumatoid wrists seem to be complicated, involving combined laxity of the intrinsic and extrinsic carpal ligaments.
authors: Department of Orthopedic Surgery and Rheumatology, Yamaguchi University School of Medicine, 1-1-1 Minami-Kogushi, Ube, 755-8505 Yamaguchi, Japan. muramatu@po.cc.yamaguchi-u.ac.jp
authors: Keiichi
authors: K
authors: Muramatsu
authors: Koichiro
authors: K
authors: Ihara
authors: Hiroshi
authors: H
authors: Tanaka
authors: Shinya
authors: S
authors: Kawai
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002348:Carpal Bones / Q000000981:diagnostic imaging* / Q000503:physiopathology; D018450:Disease Progression; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008022:Ligaments / Q000000981:diagnostic imaging / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011859:Radiography; D014955:Wrist Joint / Q000000981:diagnostic imaging* / Q000503:physiopathology