title: Head eye co-ordination using simultaneous measurement of eye in head and head in space movements: potential for use in subjects with a whiplash injury.
abstract: OBJECTIVE
  Describe reproducibility of a measurement method to investigate deficits in eye-head co-ordination.
  
  
  METHODS
  Combined recordings of head and eye rotation using wireless motion sensors and electro-oculography (EOG) were used as an initial step towards a method to quantify eye-head co-ordination deficits. Head rotation to the side during gaze fixation and sequential head and eye movements were studied on 20 asymptomatic control subjects and six subjects with chronic whiplash disorders. All included whiplash subjects reported eye disturbances according to a vision symptom questionnaire.
  
  
  RESULTS
  The trial-to-trial reproducibility was moderate to high for 24 of 28 variables (Intraclass Correlation Coefficient 0.44 to 0.87). Velocity gain (ratio of eye and head velocities) was on average close to unity in both groups. Head stability was high in control subjects, while three of six whiplash subjects demonstrated head instability during eye movement. Whiplash subjects also demonstrated a decreased range of head movement during gaze fixation and lower head velocities as compared with the asymptomatics.
  
  
  CONCLUSIONS
  The method of combined head and eye motion appears to give accurate, repeatable measurements. Case studies of whiplash subjects indicated deficits in head eye co-ordination. The method could be useful in further clinical research into eye and head movement in those with neck disorders.
authors.affiliation: Department of Biomedical Engineering and Informatics, University Hospital of Umeå, Umeå, 90185, Sweden. helena.grip@vll.se
authors.forename: Helena
authors.initials: H
authors.lastname: Grip
authors.forename: Gwendolen
authors.initials: G
authors.lastname: Jull
authors.forename: Julia
authors.initials: J
authors.lastname: Treleaven
mesh_terms: D000054:Acceleration; D000328:Adult; D004585:Electrooculography / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005133:Eye Movements; D005260:Female; D019416:Head Movements; D006801:Humans; D008297:Male; D009048:Motor Skills; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014159:Transducers; D014911:Whiplash Injuries / Q000175:diagnosis* / Q000503:physiopathology*