title: Lumbar lordosis. Effects of sitting and standing.
abstract: METHODS
  The effect of sitting versus standing posture on lumbar lordosis was studied retrospectively by radiographic analysis of 109 patients with low back pain.
  
  
  OBJECTIVE
  To document changes in segmental and total lumbar lordosis between sitting and standing radiographs.
  
  
  BACKGROUND
  Preservation of physiologic lumbar lordosis is an important consideration when performing fusion of the lumbar spine. The appropriate degree of lumbar lordosis has not been defined.
  
  
  METHODS
  Total and segmental lumbar lordosis from L1 to S1 was assessed by an independent observer using the Cobb angle measurements of the lateral radiographs of the lumbar spine obtained with the patient in the sitting and standing positions.
  
  
  RESULTS
  Lumbar lordosis averaged 49 degrees standing and 34 degrees sitting from L1 to S1, 47 degrees standing and 33 degrees sitting from L2 to S1, 31 degrees standing and 22 degrees sitting from L4 to S1, and 18 degrees standing and 15 degrees sitting from L5 to S1.
  
  
  CONCLUSIONS
  Lumbar lordosis while standing was nearly 50% greater on average than sitting lumbar lordosis. The clinical significance of this data may pertain to: 1) the known correlation of increased intradiscal pressure with sitting, which may be caused by this decrease in lordosis; 2) the benefit of a sitting lumbar support that increases lordosis; and 3) the consideration of an appropriate degree of lordosis in fusion of the lumbar spine.
authors.affiliation: Kerlan-Jobe Orthopaedic Clinic, Inglewood, California, USA.
authors.forename: M J
authors.initials: MJ
authors.lastname: Lord
authors.forename: J M
authors.initials: JM
authors.lastname: Small
authors.forename: J M
authors.initials: JM
authors.lastname: Dinsay
authors.forename: R G
authors.initials: RG
authors.lastname: Watkins
mesh_terms: D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000502:physiology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D011187:Posture / Q000502:physiology*; D011859:Radiography; D012189:Retrospective Studies; D013123:Spinal Fusion