title: A case-control study examining the role of physical trauma in the onset of rheumatoid arthritis.
abstract: OBJECTIVE
  To investigate whether physical trauma may precipitate the onset of rheumatoid arthritis (RA).
  
  
  METHODS
  In a case-control study comparing RA out-patients with controls attending non-rheumatology out-patient clinics, 262 patients and 262 age- and sex-matched controls completed a postal questionnaire or were interviewed about any physical trauma in the 6 months before the onset of their symptoms.
  
  
  RESULTS
  Fifty-five (21%) of the RA patients reported significant physical trauma in the 6 months before the onset of their disease, compared with only 17 (6.5%) of the controls (P<0.00001). A preceding history of physical trauma was significantly more common in RA patients who were seronegative for rheumatoid factor (P=0.03), but was not significantly associated with sex (P=0.78), age (P=0.64), a family history of RA (P=0.07) or type of occupation, defined as manual or sedentary (P=0.6).
  
  
  CONCLUSIONS
  Physical trauma in the preceding 6 months is significantly associated with the onset of RA.
authors: Department of Rheumatology, Devonshire Royal Hospital, Buxton, Derbyshire SK17 6RX, UK.
authors: A W
authors: AW
authors: Al-Allaf
authors: P A
authors: PA
authors: Sanders
authors: S A
authors: SA
authors: Ogston
authors: J S
authors: JS
authors: Marks
mesh_terms: D001172:Arthritis, Rheumatoid / Q000209:etiology* / Q000503:physiopathology*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013223:Statistics as Topic; D011795:Surveys and Questionnaires; D013997:Time Factors; D014947:Wounds and Injuries / Q000150:complications* / Q000503:physiopathology*