title: The persistence of lumbar somatic dysfunction and its association with bone mineral density.
abstract: BACKGROUND
  Clinically meaningful somatic dysfunction, if left untreated, should persist over time and be associated with objective measurable findings.
  
  
  OBJECTIVE
  To investigate the persistence of lumbar somatic dysfunction over 8 weeks and the association of that persistence with lumbar bone mineral density (BMD) T scores.
  
  
  METHODS
  Individuals were assessed at 0, 4, and 8 weeks for the presence and severity of paraspinal tissue texture abnormalities (TTA), vertebral rotational asymmetry, anterior motion restriction, and tenderness from L1 to L4. Participants underwent dual-energy x-ray absorptiometry of the lumbar spine at 0 and 8 weeks. Persistent somatic dysfunction findings from all 3 examinations were compared with BMD T scores obtained at 8 weeks and to changes in the BMD T scores from 0 to 8 weeks.
  
  
  RESULTS
  Forty-eight individuals (38 women [79%] and 10 men [21%]) participated in the study. The mean (standard deviation [SD]) age was 30.1 (6.4) years (range, 20.0-40.8 years), and the mean (SD) body mass index was 26.3 (5.2). The percentage of vertebrae with persistent somatic dysfunction varied by vertebral level and ranged from 44% to 83% for TTA, 63% to 79% for rotational asymmetry, 10% to 56% for motion restriction, and 2% to 10% for tenderness. Vertebral segments with persistent motion restriction had higher mean BMD T scores (95% confidence interval [CI]) than those without persistent motion restriction (0.6 [0.4 to 0.8] vs 0.2 [0.1 to 0.4], respectively; P=.02). There was a significant increase in the vertebral BMD T scores for those vertebrae that demonstrated persistent TTA (P=.02) and for those vertebrae that demonstrated persistent moderate/severe TTA (P=.02). A significant difference was found in the initial to final vertebral BMD T-score change between vertebrae that demonstrated persistent tenderness and those that did not (mean [95% CI] change, -0.2 [-0.4 to 0.1] vs 0.1 [0.0 to 0.1], respectively; P=.04).
  
  
  CONCLUSIONS
  A persistence of predominantly left lumbar rotation was observed. Persistent vertebral motion restriction was shown to have an association with final lumbar BMD T scores, and persistent TTA and tenderness were associated with changes in the BMD T scores over 8 weeks.
authors.affiliation: Department of Osteopathic Manipulative Medicine, A.T. Still University-Kirksville College of Osteopathic Medicine, 800 W Jefferson St, Kirksville, MO 63501-1443. ksnider@atsu.edu.
authors.forename: Karen T
authors.initials: KT
authors.lastname: Snider
authors.forename: Jane C
authors.initials: JC
authors.lastname: Johnson
authors.forename: Brian F
authors.initials: BF
authors.lastname: Degenhardt
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Snider
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D015519:Bone Density / Q000502:physiology*; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000503:physiopathology; D008159:Lumbar Vertebrae / Q000503:physiopathology*; D008297:Male; D016059:Range of Motion, Articular / Q000502:physiology*; D012399:Rotation; D055815:Young Adult