title: Exposure-response relationships between movements and postures of the wrist and carpal tunnel syndrome among male and female house painters: a retrospective cohort study.
abstract: To investigate exposure-response relationships between measured movements and postures of the wrist and the incidence of carpal tunnel syndrome (CTS), and any modifications by sex.
  
  
  
  In 2011, we established a historical cohort of 9364 members of the Painters' Union in Denmark. Self-reported task distributions were obtained by questionnaire (53% responded) and combined with sex-specific task exposure matrices to get individual estimates of exposure intensity, that is, velocity of wrist flexion/extension, mean power frequency (MPF) and non-neutral wrist postures. Exposure duration was assessed from yearly working proportions. Registered first-time hospital discharge CTS diagnoses and CTS surgery were collected as outcomes. The cohort was followed from 1994 to 2010. Log-linear Poisson regression was used.
  
  
  
  For CTS diagnoses, the adjusted incidence rate ratios (IRRs) increased with increasing wrist velocity (IRR=1.37 (95% CI 1.10 to 1.71) per °/s) and MPF (IRR=1.53 (95% CI 1.21 to 1.91) per 0.01 Hz). For CTS surgery, the results were similar. The outcomes were not related to non-neutral postures or exposure duration. The adjusted IRRs for women were higher than those for men. There were no multiplicative interaction effects between exposure intensity, exposure duration and sex. However, the absolute incidence rates (IRs) increased at a steeper rate for women than for men, indicating an additive interaction.
  
  
  
  The incidence of CTS increased with increasing velocity of wrist flexion/extension and MPF of wrist movements. The relative increase in incidence rates was the same for women and men, but the absolute incidence rates increased at a steeper rate for women than for men.
authors.affiliation: Department of Occupational and Environmental Medicine, Bispebjerg University Hospital, Copenhagen, Denmark.
authors.forename: Thomas
authors.initials: T
authors.lastname: Heilskov-Hansen
authors.affiliation: Department of Occupational and Environmental Medicine, Bispebjerg University Hospital, Copenhagen, Denmark.
authors.forename: Sigurd
authors.initials: S
authors.lastname: Mikkelsen
authors.affiliation: Department of Occupational Medicine, Danish Ramazzini Centre, Regional Hospital West Jutland-University Research Clinic, Herning, Denmark.
authors.forename: Susanne Wulff
authors.initials: SW
authors.lastname: Svendsen
authors.affiliation: National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark.
authors.forename: Lau Caspar
authors.initials: LC
authors.lastname: Thygesen
authors.affiliation: Occupational and Environmental Medicine, Lund University, and University and Regional Laboratories Region Scania, Lund, Sweden.
authors.forename: Gert-Åke
authors.initials: GÅ
authors.lastname: Hansson
authors.affiliation: Department of Occupational and Environmental Medicine, Bispebjerg University Hospital, Copenhagen, Denmark.
authors.forename: Jane Frølund
authors.initials: JF
authors.lastname: Thomsen
mesh_terms: D000328:Adult; D050824:Carpal Joints / Q000503:physiopathology; D002349:Carpal Tunnel Syndrome / Q000453:epidemiology* / Q000209:etiology*; D015897:Comorbidity; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009068:Movement; D009784:Occupational Diseases / Q000453:epidemiology* / Q000209:etiology*; D009790:Occupations; D010150:Paint; D016012:Poisson Distribution; D011187:Posture; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014953:Wrist / Q000503:physiopathology