title: Bony ankylosis of the facet joint of the cervical spine in rheumatoid arthritis: Its characteristics and relationship to the clinical findings.
abstract: OBJECTIVE
  The purpose of this study was to clarify the characteristics of bony ankylosis of the facet joint of the cervical spine in rheumatoid arthritis (RA) patients who required cervical spine surgery, and its relationship to the clinical findings.
  
  
  METHODS
  Eighty consecutive RA patients with cervical spine disorder who received initial surgery were reviewed. The occurrence of bony ankylosis of the facet joint of the cervical spine was investigated using computed tomography (CT) before surgery. We also evaluated the severity of neurological symptoms and the plain wrist radiographs taken before surgery; furthermore, we evaluated each patient's medical history for total knee arthroplasty (TKA) or hip arthroplasty (THA).
  
  
  RESULTS
  The preoperative CT imaging demonstrated bony ankylosis of the facet joint of the cervical spine in 45 facet levels of 19 cases (BA + group). In all patients, responsible instability or stenosis was demonstrated just caudal or on the cranial side of those bony ankylosis. Before surgery, the BA + group included significantly more patients showing severe cervical myelopathy (p < 0.05), and significantly more cases showing progressed ankylosis in the wrist joint bilaterally (p < 0.01). There were also significantly more patients who received two or more TKA or THA before the cervical spine surgery in the BA + group (p < 0.01).
  
  
  CONCLUSIONS
  Bony ankylosis of the facet joint of the cervical spine may be a risk factor of instability or stenosis at the adjacent disc level and severe cervical myelopathy. Furthermore, its ankylosis was demonstrated in RA patients with severe destroyed joints.
authors.affiliation: a Department of Orthopedic Surgery , Gunma University Graduate School of Medicine , Maebashi , Japan.
authors.forename: Haku
authors.initials: H
authors.lastname: Iizuka
authors.affiliation: a Department of Orthopedic Surgery , Gunma University Graduate School of Medicine , Maebashi , Japan.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Iizuka
authors.affiliation: a Department of Orthopedic Surgery , Gunma University Graduate School of Medicine , Maebashi , Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Okamura
authors.affiliation: a Department of Orthopedic Surgery , Gunma University Graduate School of Medicine , Maebashi , Japan.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Yonemoto
authors.affiliation: a Department of Orthopedic Surgery , Gunma University Graduate School of Medicine , Maebashi , Japan.
authors.forename: Tokue
authors.initials: T
authors.lastname: Mieda
authors.affiliation: a Department of Orthopedic Surgery , Gunma University Graduate School of Medicine , Maebashi , Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Takagishi
mesh_terms: D000328:Adult; D000368:Aged; D000844:Ankylosis / Q000175:diagnosis / Q000209:etiology; D001172:Arthritis, Rheumatoid / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination / Q000379:methods / Q000706:statistics & numerical data; D019990:Perioperative Care / Q000379:methods / Q000706:statistics & numerical data; D012720:Severity of Illness Index; D013122:Spinal Diseases / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000601:surgery; D013223:Statistics as Topic; D014057:Tomography, X-Ray Computed / Q000379:methods; D021801:Zygapophyseal Joint / Q000000981:diagnostic imaging / Q000503:physiopathology
keywords: Bony ankylosis; Cervical spine; Rheumatoid arthritis