title: Anatomy of hallux valgus in rheumatoid arthritis: radiographic analysis using a two-dimensional coordinate system.
abstract: OBJECTIVE
  The purpose of this study is to compare the anatomy of rheumatoid hallux valgus with that of idiopathic hallux valgus from the standpoint of joint-preserving surgery.
  
  
  METHODS
  One hundred forty-eight feet of 81 rheumatoid patients were included. Feet with idiopathic hallux valgus and normal feet were compared as controls. Weight-bearing dorsoplantar radiographs of the feet were taken of each patient. A two-dimensional coordinate system was defined on the radiographic image, and 19 anatomic points of the forefoot were measured.
  
  
  RESULTS
  In rheumatoid hallux valgus, the first metatarsal head shifted medially as hallux valgus angle increased, which was similar to the deformity of idiopathic hallux valgus. Proximal deviation of the tips of the lesser toes, caused by clawing and dislocations of the metatarsophalangeal joints, occurred in rheumatoid hallux valgus. Specifically the tips of the second toes in rheumatoid hallux valgus were located more proximally than those in idiopathic hallux valgus irrespective of the severity of hallux valgus.
  
  
  CONCLUSIONS
  Corrective osteotomy of the first metatarsal is a reasonable procedure for rheumatoid hallux valgus. Additionally, correction of the second toe deformity to make a stable lateral support on the hallux may be another important factor for successful joint-preserving surgery.
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8677, Japan. y-satoshi@mvb.biglobe.ne.jp
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yamaguchi
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Shinohara
authors.forename: Akira
authors.initials: A
authors.lastname: Taniguchi
authors.forename: Takahisa
authors.initials: T
authors.lastname: Sasho
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Takahashi
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Takakura
mesh_terms: D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000150:complications / Q000000981:diagnostic imaging* / Q000601:surgery; D005260:Female; D006215:Hallux Valgus / Q000000981:diagnostic imaging* / Q000209:etiology / Q000601:surgery; D006801:Humans; D008297:Male; D008682:Metatarsal Bones / Q000000981:diagnostic imaging* / Q000601:surgery; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000379:methods; D010027:Osteotomy / Q000379:methods; D011859:Radiography