title: Changes in head and neck position have a greater effect on elbow joint position sense in people with whiplash-associated disorders.
abstract: BACKGROUND
  It has been shown that perception of elbow joint position is affected by changes in head and neck position. Further, people with whiplash-associated disorders (WAD) present with deficits in upper limb coordination and movement.
  
  
  OBJECTIVE
  This study is aimed to determine whether the effect of changes in head position on elbow joint position error (JPE) is more pronounced in people with WAD, and to determine whether this is related to the participant's pain and anxiety levels.
  
  
  METHODS
  Nine people with chronic and disabling WAD and 11 healthy people participated in this experiment. The ability to reproduce a position at the elbow joint was assessed after changes in the position of the head and neck to 30 degrees , and with the head in the midline. Pain was monitored in WAD participants.
  
  
  RESULTS
  Absolute elbow JPE with the head in neutral was not different between WAD and control participants (P=0.5). Changes in the head and neck position increased absolute elbow JPE in the WAD group (P<0.05), but did not affect elbow JPE in the control group (P=0.4). There was a connection between pain during testing and the effect of changes in head position on elbow JPE (P<0.05).
  
  
  CONCLUSIONS
  Elbow JPE is affected by movement of the head and neck, with smaller angles of neck rotation in people with WAD than in healthy individuals. This observation may explain deficits in upper limb coordination in people with WAD, which may be due to the presence of pain or reduced range of motion in this population.
authors.affiliation: Division of Physiotherapy, The University of Queensland, Brisbane, Australia.
authors.forename: Joanna Joy
authors.initials: JJ
authors.lastname: Knox
authors.forename: Darren Jay
authors.initials: DJ
authors.lastname: Beilstein
authors.forename: Scott Darren
authors.initials: SD
authors.lastname: Charles
authors.forename: Geir Arne
authors.initials: GA
authors.lastname: Aarseth
authors.forename: Shivanthi
authors.initials: S
authors.lastname: Rayar
authors.forename: Julia
authors.initials: J
authors.lastname: Treleaven
authors.forename: Paul William
authors.initials: PW
authors.lastname: Hodges
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D004185:Disability Evaluation; D004551:Elbow Joint / Q000294:innervation* / Q000503:physiopathology; D004576:Electromyography / Q000379:methods; D005260:Female; D006257:Head; D006801:Humans; D008297:Male; D009068:Movement / Q000502:physiology; D009333:Neck; D010147:Pain Measurement / Q000379:methods; D011187:Posture / Q000502:physiology*; D011434:Proprioception; D014911:Whiplash Injuries / Q000503:physiopathology*