title: The prevalence of knee pain and symptomatic knee osteoarthritis among veteran traumatic amputees and nonamputees.
abstract: OBJECTIVE
  To determine whether amputees have an increased risk of knee pain or symptomatic osteoarthritis (OA) compared with nonamputees.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Veterans Administration Patient Treatment and Outpatient Care files.
  
  
  METHODS
  All male unilateral (transtibial or transfemoral) traumatic amputee patients and a random sample of male nonamputees. Patients were excluded if they were younger than 40 years, had sustained a significant injury to their knee(s), or had a rheumatic disease.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  The prevalence of knee pain and symptomatic knee OA.
  
  
  RESULTS
  The age and average weight-adjusted prevalence ratio of knee pain among transtibial amputees, compared with nonamputees, was 1.3 (95% confidence interval [CI], 0.7-2.1) for the knee of the intact limb and 0.2 (95% CI, .05-0.7) for the knee of the amputated limb. The standardized prevalence ratio of knee pain in the intact limb and symptomatic OA among transfemoral amputees, compared with nonamputees, was 3.3 (95% CI, 1.5-6.3) and 1.3 (95% CI, 0.2-4.8), respectively.
  
  
  CONCLUSIONS
  Stresses on the contralateral knee of amputees may contribute to secondary disability. Possible explanations include gait abnormalities, increased physiologic loads on the knee of the intact limb, and the hopping and stumbling behavior common in many younger amputees.
authors.affiliation: Health Services Research and Development, Seattle, WA, USA. dan@olympicresearch.com
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Norvell
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Czerniecki
authors.forename: Gayle E
authors.initials: GE
authors.lastname: Reiber
authors.forename: Charles
authors.initials: C
authors.lastname: Maynard
authors.forename: Janice A
authors.initials: JA
authors.lastname: Pecoraro
authors.forename: Noel S
authors.initials: NS
authors.lastname: Weiss
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D000673:Amputation, Traumatic / Q000150:complications*; D000674:Amputees / Q000534:rehabilitation*; D016001:Confidence Intervals; D006787:Hospitals, Veterans; D006801:Humans; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000453:epidemiology*; D010146:Pain / Q000145:classification / Q000209:etiology*; D015995:Prevalence; D012189:Retrospective Studies; D014481:United States / Q000453:epidemiology; D014728:Veterans