title: Wrist posture during computer pointing device use.
abstract: OBJECTIVE
  This research examines individual differences in the wrist postures adopted during the use of two pointing devices (mouse and trackball).
  
  
  METHODS
  A multiple case study of twelve participants was employed.
  
  
  BACKGROUND
  The use of pointing devices may lead to musculoskeletal discomfort and injury as a consequence of prolonged exposure to postures involving wrist extension and ulnar deviation.
  
  
  METHODS
  Wrist flexion/extension and radial/ulnar deviation was measured while twelve participants completed two standardised tasks involving horizontal and vertical cursor movements respectively.
  
  
  RESULTS
  Exposure to extreme ulnar deviation and wrist extension was observed in the use of computer mouse and trackball. The trackball involved decreased ulnar deviation and increased wrist extension, however considerable individual differences were observed.
  
  
  CONCLUSIONS
  Some users may be placed at risk of injury by prolonged exposure to the use of such devices, while others may not. A trackball may reduce the exposure to extreme ulnar deviation, but in some cases, a trackball may increase exposure to extreme wrist extension.
authors.affiliation: Department of Human Movement Studies, University of Queensland, Brisbane, Australia. robin@hms.uq.edu.au
authors.forename: R
authors.initials: R
authors.lastname: Burgess-Limerick
authors.forename: J
authors.initials: J
authors.lastname: Shemmell
authors.forename: R
authors.initials: R
authors.lastname: Scadden
authors.forename: A
authors.initials: A
authors.lastname: Plooy
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001696:Biomechanical Phenomena; D016287:Computer Peripherals; D005260:Female; D006801:Humans; D008297:Male; D011187:Posture / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology; D014955:Wrist Joint / Q000502:physiology*