title: Decreased muscle strength and mobility of the neck in patients with rheumatoid arthritis and atlantoaxial disorders.
abstract: OBJECTIVE
  To compare neck muscle strength and mobility of the cervical spine in rheumatoid arthritis (RA) patients with and without atlantoaxial (AA) disorders (anterior atlantoaxial subluxation [AAS], AA impaction).
  
  
  METHODS
  Clinical cross-sectional study.
  
  
  METHODS
  Outpatient rheumatology and rehabilitation clinics in a Finnish hospital.
  
  
  METHODS
  Patients with RA (N=124; mean age +/- standard deviation, 62+/-12y [corrected]) on a waiting list for orthopedic surgery. Thirty (24%) patients presented with AA disorders (16 with anterior AAS, 8 with AA impaction, 6 with a combination of anterior AAS and AA impaction).
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  Neck function was measured by isometric neck strength and mobility tests, neck pain by a visual analog scale, erosion of the hands and feet by radiography, and the patients' function by the Health Assessment Questionnaire (HAQ).
  
  
  RESULTS
  Maximal neck muscle strength against flexion, extension, and rotation was lower in patients with AA disorders compared with the other patients in both women (P=.012) and men (P=.017). Mobility was lowest in the AA impaction group in all measured directions (P<.001). Peripheral erosive disease was more frequent in the group with AA disorders. They also had longer disease duration and were more disabled (HAQ) than the other patients.
  
  
  CONCLUSIONS
  Neck muscle strength is significantly decreased in patients with AA disorders. Mobility of the cervical spine is most limited in patients with AA impaction, but can be normal in cases with solitary anterior AAS.
authors.affiliation: Department of Physical Medicine and Rehabilitation, Jyväskylä Central Hospital, Jyväskylä, Finland. arja.hakkinen@ksshp.fi
authors.forename: Arja
authors.initials: A
authors.lastname: Häkkinen
authors.forename: Marko Henrik
authors.initials: MH
authors.lastname: Neva
authors.forename: Markku
authors.initials: M
authors.lastname: Kauppi
authors.forename: Pekka
authors.initials: P
authors.lastname: Hannonen
authors.forename: Jari
authors.initials: J
authors.lastname: Ylinen
authors.forename: Heidi
authors.initials: H
authors.lastname: Mäkinen
authors.forename: Irma
authors.initials: I
authors.lastname: Jäppinen
authors.forename: Tuulikki
authors.initials: T
authors.lastname: Sokka
mesh_terms: D001172:Arthritis, Rheumatoid / Q000503:physiopathology*; D001268:Atlanto-Axial Joint / Q000503:physiopathology*; D002574:Cervical Vertebrae / Q000503:physiopathology*; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009334:Neck Muscles / Q000503:physiopathology*; D019547:Neck Pain / Q000503:physiopathology; D010147:Pain Measurement; D016059:Range of Motion, Articular