title: Computer use increases the risk of musculoskeletal disorders among newspaper office workers.
abstract: BACKGROUND
  Our objectives were to estimate prevalence of musculoskeletal disorders among office workers at a newspaper in Mexico City, analyze the relationship between musculoskeletal disorders and use of the personal computer (PC) and associated ergonomic factors in the aforementioned population, and to analyze the modifying effect that psychosocial factors have on the relationship between ergonomic factors and musculoskeletal disorders and extant jobs at the newspaper.
  
  
  METHODS
  A total of 73% (218 of 298) of office workers at a newspaper were studied. Information was collected by a questionnaire completed by participants. Cases for work-related musculoskeletal disorder in hands (WMSD-H), upper extremity (WMSD-UE), and back (WMSD-B) were established. Working conditions, computer use, and ergonomic and psychosocial factors were studied as independent variables. To study the relationship between musculoskeletal disorders and independent variables, prevalence ratios adjusted for potential confounders (sex, age, educational level, and marital status) were estimated.
  
  
  RESULTS
  Risk of musculoskeletal disorders was greater among workers at the newspaper who used computers, those involved in editing work, and those who adopted uncomfortable positions. The modifying effect of psychosocial factors was observed only in the relationship between ergonomic factors and WMSD-B because among workers with control over work, WMSD-B risk was reduced by the greater number of work breaks. Among workers without social support, increase in number of postures and rotation/inclination of the neck was associated with substantial risk increase, while amid workers under psychological demand number of PC tasks and number of rest pauses were associated with increase in WMSD-B risk.
  
  
  CONCLUSIONS
  The findings of our study showed that PC use increased risk of developing musculoskeletal disorders (WMSD-H and WMSD-UE). Such an increase is mediated by ergonomic factors such as mouse use, remaining seated for prolonged periods, adoption of inadequate or uncomfortable postures, performing certain PC tasks, and psychosocial factors.
authors.affiliation: Departamento de Atención a la Salud, División de Ciencias Biológicas y de la Salud, Universidad Autónoma de México Campus Xochimilco, Mexico City, Mexico. lortiz@cueyatl.uam.mx
authors.forename: Luis
authors.initials: L
authors.lastname: Ortiz-Hernández
authors.forename: Silvia
authors.initials: S
authors.lastname: Tamez-González
authors.forename: Susana
authors.initials: S
authors.lastname: Martínez-Alcántara
authors.forename: Ignacio
authors.initials: I
authors.lastname: Méndez-Ramírez
mesh_terms: D000328:Adult; D001416:Back Pain / Q000209:etiology; D016288:Computer Terminals; D006804:Ergonomics; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009140:Musculoskeletal Diseases / Q000209:etiology*; D009524:Newspapers as Topic; D009784:Occupational Diseases / Q000209:etiology; D012306:Risk; D013997:Time Factors