title: Postural control in individuals with and without non-specific chronic low back pain: a preliminary case-control study.
abstract: METHODS
  A preliminary case-control study.
  
  
  OBJECTIVE
  To assess postural control in individuals with and without non-specific chronic low back pain (cLBP) during quiet standing. cLBP affects 12-33 % of the adult population. Reasons for pain chronicity are yet poorly known. Change in postural control may be a risk factor for cLBP, although available studies are not conclusive.
  
  
  METHODS
  Sample consisted of 21 individuals with cLBP and 23 controls without cLBP. Balance was assessed using a force plate (Balance Master, NeuroCom) by the modified clinical test of sensory interaction and balance, pain severity by the visual analogue scale, quality of life with the SF-36 Questionnaire, and functional disability with the Roland-Morris Questionnaire.
  
  
  RESULTS
  Groups were homogeneous for age, weight, height and body mass index. Relative to controls, participants in the cLBP group had deficits in the postural control, with greater postural sway in the quiet standing condition with closed eyes closed on unstable surfaces (p < 0.05) for the following parameters: total COP oscillation [cLBP 1,432.82 (73.27) vs CG 1,187.77 (60.30)], root mean square sagittal plane [cLBP 1.21 (0.06) vs CG 1.04 (0.04)], COP area [cLBP 24.27 (2.47) vs CG 16.45 (1.79)] and mean speed of oscillation [cLBP 12.97 (0.84) vs CG 10.55 (0.70)].
  
  
  CONCLUSIONS
  Postural control, as evidenced by increased oscillation of COP, is impaired in individuals with cLBP relative to controls. Differences are magnified by visual deprivation and unstable surface conditions.
authors.affiliation: Department of Speech, Physical and Occupational Therapy, School of Medicine, University of Sao Paulo, São Paulo, Brazil.
authors.forename: Rene Rogieri
authors.initials: RR
authors.lastname: Caffaro
authors.forename: Fábio Jorge Renovato
authors.initials: FJ
authors.lastname: França
authors.forename: Thomaz Nogueira
authors.initials: TN
authors.lastname: Burke
authors.forename: Maurício Oliveira
authors.initials: MO
authors.lastname: Magalhães
authors.forename: Luiz Armando Vidal
authors.initials: LA
authors.lastname: Ramos
authors.forename: Amélia Pasqual
authors.initials: AP
authors.lastname: Marques
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D059350:Chronic Pain / Q000503:physiopathology*; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D004856:Postural Balance; D011788:Quality of Life