title: Gender differences in workers with identical repetitive industrial tasks: exposure and musculoskeletal disorders.
abstract: OBJECTIVE
  For unknown reasons, females run a higher risk than males of work-related musculoskeletal disorders. The aim of this study was to evaluate whether male and female workers, with identical repetitive work tasks, differ concerning risk of disorders, physical or psychosocial exposures.
  
  
  METHODS
  Employees in two industries were studied; one rubber manufacturing and one mechanical assembly plant. These industries were selected since in both, large groups of males and females worked side by side performing identical repetitive work tasks. Physical exposure was measured by technical equipment. Postures and movements were registered by inclinometry for the head and upper arms, and by electrogoniometry for the wrists. Muscular activity (muscular rest and %max) was registered by surface electromyography for m. trapezius and the forearm extensors (18 males and 19 females). Psychosocial work environment was evaluated by the demand-control-support model (85 males and 138 females). Musculoskeletal disorders were assessed (105 males and 172 females), by interview (last 7-days complaints), and by physical examination (diagnoses).
  
  
  RESULTS
  Concerning physical exposure, females showed higher muscular activity related to maximal voluntary contractions [(%MVE); m. trapezius: females 18 (SD 9.2), males 12 (SD 4.3); forearm extensors: females 39 (SD 11), males 27 (SD 10), right side, 90th percentile]. Working postures and movements were similar between genders. Also, concerning psychosocial work environment, no significant gender differences were found. Females had higher prevalences of disorders [complaints: age-adjusted prevalence odds ratio (POR) 2.3 (95% CI 1.3-3.8) for neck/shoulders, 2.4 (1.4-4.0) for elbows/hands; diagnoses: neck/shoulder 1.9 (1.1-3.6), elbows/hands 4.1 (1.2-9.3)]. In 225 workers, PORs were adjusted for household work, personal recovery and exercise, which only slightly affected the risk estimates.
  
  
  CONCLUSIONS
  In identical work tasks, females showed substantially higher muscular activity in relation to capacity, and higher prevalence of musculoskeletal disorders of the neck and upper extremity, than did males.
authors: Department of Occupational and Environmental Medicine, University Hospital, Lund, Sweden. catarina.nordander@med.lu.se
authors: Catarina
authors: C
authors: Nordander
authors: Kerstina
authors: K
authors: Ohlsson
authors: Istvan
authors: I
authors: Balogh
authors: Gert-Ake
authors: GA
authors: Hansson
authors: Anna
authors: A
authors: Axmon
authors: Roger
authors: R
authors: Persson
authors: Staffan
authors: S
authors: Skerfving
mesh_terms: D000328:Adult; D012090:Cumulative Trauma Disorders / Q000209:etiology*; D004576:Electromyography; D004784:Environmental Monitoring / Q000379:methods; D005260:Female; D006801:Humans; D007221:Industry; D008297:Male; D009140:Musculoskeletal Diseases / Q000209:etiology*; D009784:Occupational Diseases / Q000209:etiology*; D012307:Risk Factors; D012737:Sex Factors; D018582:Sick Leave / Q000706:statistics & numerical data; D013647:Task Performance and Analysis