title: The impact of ergonomics intervention on trunk posture and cumulative compression load among carpet weavers.
abstract: BACKGROUND
  Work-related musculoskeletal disorders of back among weavers are prevalent. Epidemiological studies have shown an association between poor working postures and back disorders among carpet weavers. Therefore, the present study aimed to evaluate the impact of the traditional (A) and ergonomically designed (B) workstations on trunk posture and cumulative compression load in carpet weavers.
  
  
  METHODS
  In this study, subtasks were identified in terms of stressful postures and carpet weaving process. Postural data were collected during knotting and compacting subtasks using inclinometer during four hours for each workstation. Postural data, weight and height of the weavers were entered into the University of Michigan three-dimensional static biomechanical model for estimation of the compression load and cumulative load were estimated from the resultant load and exposure time.
  
  
  METHODS
  Thirteen healthy carpet weavers (four males and nine females) participated in the study.
  
  
  RESULTS
  Median trunk flexion angle was reduced with workstation B during knotting subtask (18° versus 8.5°, p< 0.01 in males; 18.5° versus 7°, p< 0.001 in females). Average cumulative compression load was reduced with workstation B (22.17MN-s versus 16.68MN-s, p < 0.01 in males; 13.05 MN-s versus 10.14, p < 0.001 in females).
  
  
  CONCLUSIONS
  Using workstation B led to significant decrease in cumulative compressive loading during an entire shift (8 hours), which indicates reduced level of stress on the back. It is suggested to conduct biomechanical studies on the shoulder and wrist regions in carpet weavers in order to achieve further development and improvement in the ergonomically designed workstation.
authors.affiliation: Department of Occupational Health, School of Public Health and Research Centre for Health Sciences, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Davood
authors.initials: D
authors.lastname: Afshari
authors.affiliation: Ergonomics Department, School of Public Health and Research Centre for Health Sciences, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Majid
authors.initials: M
authors.lastname: Motamedzade
authors.affiliation: School of Rehabilitation, Musculoskeletal Rehabilitation Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Salehi
authors.affiliation: Department of Biostatistics and Epidemiology and Research Center for Health Sciences, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Alir Raze
authors.initials: AR
authors.lastname: Soltanian
mesh_terms: D000328:Adult; D004867:Equipment Design / Q000401:mortality; D006804:Ergonomics / Q000379:methods*; D005260:Female; D005430:Floors and Floorcoverings; D006801:Humans; D007492:Iran / Q000453:epidemiology; D008297:Male; D009784:Occupational Diseases / Q000453:epidemiology; D011187:Posture / Q000502:physiology*; D013783:Textile Industry / Q000379:methods / Q000706:statistics & numerical data
keywords: Iran; Spinal load; musculoskeletal disorders; workstation design