title: Changes in head and neck posture using an office chair with and without lumbar roll support.
abstract: METHODS
  A repeated measures observational study.
  
  
  OBJECTIVE
  To investigate change in sagittal alignment of head and neck posture in response to adjustments of an office chair with and without a lumbar roll in situ.
  
  
  BACKGROUND
  Forward head posture has been identified as a risk factor for neck pain, and there is evidence to show that ergonomic correction in sitting may reduce the incidence of pain. The effect placement of a lumbar roll has on cervical spine posture has not been previously investigated experimentally but rather, is assumed to have a positive influence on head and neck posture.
  
  
  METHODS
  Thirty healthy male participants (18-30 years) were photographed while registered in the natural head resting position in each of 4 sitting positions with and without a lumbar roll in situ. Two positions incorporated adjustments to the back rest and 1 to the seat pan of the office chair. The craniovertebral (CV) angle, as a determinant of head and neck posture was measured from the set of digitized photographs obtained for each participant. Comparisons between the CV angle in all postural registrations were made using a mixed model analysis adjusted for multiple comparisons.
  
  
  RESULTS
  Of the positions examined, significant differences in the mean CV angles were found with the backrest of the chair at 100 degrees and at 110 degrees (P < 0.001). With the lumbar roll in situ and the backrest position at 110 degrees , there was a significant increase in the mean CV compared with the angle without the lumbar roll in situ (2.32 degrees , 95% confidence interval: 1.31-3.33; P < 0.001).
  
  
  CONCLUSIONS
  The degree of angulation of the backrest support of an office chair plus the addition of lumbar roll support are the 2 most important factors to be taken into account when considering seating factors likely to favorably change head and neck postural alignment, at least in asymptomatic subjects.
authors.affiliation: School of Physiotherapy, University of Otago, Dunedin, New Zealand. stuart.horton@otago.ac.nz
authors.forename: Stuart J
authors.initials: SJ
authors.lastname: Horton
authors.forename: Gillian M
authors.initials: GM
authors.lastname: Johnson
authors.forename: Margot A
authors.initials: MA
authors.lastname: Skinner
mesh_terms: D000293:Adolescent; D000328:Adult; D004867:Equipment Design / Q000379:methods / Q000592:standards*; D006257:Head; D019416:Head Movements / Q000502:physiology*; D006801:Humans; D007374:Interior Design and Furnishings / Q000379:methods / Q000592:standards*; D008161:Lumbosacral Region / Q000502:physiology*; D008297:Male; D009333:Neck; D009334:Neck Muscles / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D055815:Young Adult