title: Effect of a kneeling chair on lumbar curvature in patients with low back pain and healthy controls: A pilot study.
abstract: BACKGROUND
  The concept of an ideal sitting posture is often used in practice but lacks a basis in evidence.
  
  
  OBJECTIVE
  We designed a cross-sectional, comparative, matched study to determine the effects of chair and posture on lumbar curvature in 10 patients with chronic non-specific low back pain (CLBP; mean pain duration 24 ± 18 months) and 10 healthy matched controls.
  
  
  METHODS
  Pelvic incidence, sacral slope and lumbar curvature were measured on computed radiographs by 2 blinded clinicians for subjects in 2 postures (upright vs slumped sitting) and on 2 chairs (usual flat chair vs kneeling chair).
  
  
  RESULTS
  The reliability of measures was excellent (intraclass correlation coefficient>0.9). As hypothesized, the expected sacral slope and lumbar lordosis changed between standing and sitting on a kneeling chair as compared with a usual chair (P<0.0001) and less in patients than controls (P=0.046) for lordosis only. In addition, as expected, changes were more pronounced with slumped than upright sitting (P<0.0001). An interaction between chairs and postures for lumbar lordosis (P=0.02) indicated more pronounced effects of the chair in slumped sitting. Therefore, lumbar lordosis was reduced less when sitting on a kneeling chair as compared with a usual chair.
  
  
  CONCLUSIONS
  Although healthy subjects showed more reduction in lordosis between standing and sitting, the chair effect was found in both CLBP patients and healthy subjects.
authors.affiliation: Fédération de médecine physique et de réadaptation, GHU Carémeau, université de Montpellier 1, place du Pr. Robert-Debré, 30029 Nîmes cedex 9, France.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Vaucher
authors.affiliation: Département de médecine physique et de réadaptation, institut universitaire de réadaptation Clémenceau (IURC), 67082 Strasbourg, France.
authors.forename: Marie-Eve
authors.initials: ME
authors.lastname: Isner-Horobeti
authors.affiliation: Département de biostatistiques, épidémiologie, santé publique et information médicale (BESPIM), université de Montpellier 1, Nîmes, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Demattei
authors.affiliation: Département de biostatistiques, épidémiologie, santé publique et information médicale (BESPIM), université de Montpellier 1, Nîmes, France.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Alonso
authors.affiliation: Service central de rééducation, CHU Lapeyronie, université de Montpellier 1, 34295 Montpellier, France.
authors.forename: Christian
authors.initials: C
authors.lastname: Hérisson
authors.affiliation: Département de chirurgie orthopédique, GHU Carémeau, université de Montpellier 1, 30029 Nîmes, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Kouyoumdjian
authors.affiliation: MOVE research institute Amsterdam, faculty of human movement sciences, VU university Amsterdam, Amsterdam, Netherlands; King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: Jaap H
authors.initials: JH
authors.lastname: van Dieën
authors.affiliation: Fédération de médecine physique et de réadaptation, GHU Carémeau, université de Montpellier 1, place du Pr. Robert-Debré, 30029 Nîmes cedex 9, France; Movement to Health Laboratory (M2H), Montpellier-1 University EuroMov, 34090 Montpellier, France. Electronic address: arnaud.dupeyron@univ-montp1.fr.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Dupeyron
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D004867:Equipment Design; D005260:Female; D006801:Humans; D007374:Interior Design and Furnishings / Q000295:instrumentation*; D008141:Lordosis / Q000150:complications / Q000503:physiopathology*; D017116:Low Back Pain / Q000209:etiology / Q000503:physiopathology*; D008159:Lumbar Vertebrae / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010388:Pelvis; D010865:Pilot Projects; D011187:Posture / Q000502:physiology*; D012447:Sacrum
keywords: Chair; Low back pain; Lumbar lordosis; Sitting