title: Aging changes in lumbar discs and vertebrae and their interaction: a 15-year follow-up study.
abstract: BACKGROUND
  Many studies have focused on either the intervertebral disc as a culprit in back pain problems, or the vertebral body, but very few studies have examined both structures and their relationship.
  
  
  OBJECTIVE
  To measure the concordant changes in morphology of the discs and vertebrae during 5-, 10-, and 15-year follow-ups.
  
  
  METHODS
  Longitudinal study.
  
  
  METHODS
  Among a general population sample of 232 men that had been scanned in 1992-1993, 105 men were reexamined in 1997-1998 and 2007-2008. Mean age at the 15-year follow-up was 63 years. A confirmatory sample with 10 years follow-up was also included.
  
  
  METHODS
  Scanners (1.5 Tesla) with surface coils were used at baseline and follow-up. Image analyzing software was used to measure distances and areas of interest of midsagittal and midaxial spine images.
  
  
  RESULTS
  The disc heights decreased at 5 years by 3.4% (0.4 mm) and 3.3% (0.4 mm) and at 15 years by 8.7% (1.0 mm) and 11.3% (1.3 mm) in the upper and lower discs, respectively (p<.001). Although not clear after 5 years, vertebra heights increased in mean by 3.1% (0.8 mm) in the upper lumbar levels and by 4.7% (1.1 mm) in the lower vertebrae after 15 years (p<.001). Vertebra height increases were associated with disc narrowing (p=.001). The mean annual shortening of the lumbar spine L1-S1 block was 0.13 mm/y, which was in line with the mean standing height that decreased little (174.7 cm at baseline and 174.4 cm at the follow-up).
  
  
  CONCLUSIONS
  Discs and vertebrae degenerate or remodel in concert: decreases in disc height appear to be compensated, in part, by accompanying increases in adjacent vertebra heights. The mechanism behind this novel finding and its implications require further study.
authors.affiliation: Department of Physical Therapy, Faculty of Rehabilitation Medicine, University of Alberta, 3-44 Corbett Hall, Edmonton, AB, Canada T6G 2G4. Electronic address: tapio.videman@ualberta.ca.
authors.forename: Tapio
authors.initials: T
authors.lastname: Videman
authors.affiliation: Department of Physical Therapy, Faculty of Rehabilitation Medicine, University of Alberta, 3-44 Corbett Hall, Edmonton, AB, Canada T6G 2G4.
authors.forename: Michele C
authors.initials: MC
authors.lastname: Battié
authors.affiliation: General Internal Medicine, Harborview Medical Center , University of Washington, Box 359780, 325 Ninth Ave, Seattle, WA 98104, USA.
authors.forename: Laura E
authors.initials: LE
authors.lastname: Gibbons
authors.affiliation: University of Texas Southwestern Medical Center, Department of Orthopaedic Surgery, 1801 Inwood Road, Dallas, TX 75390 USA.
authors.forename: Kevin
authors.initials: K
authors.lastname: Gill
mesh_terms: D000368:Aged; D000375:Aging / Q000473:pathology*; D001416:Back Pain / Q000453:epidemiology; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007403:Intervertebral Disc / Q000473:pathology*; D055959:Intervertebral Disc Degeneration / Q000150:complications / Q000473:pathology*; D008137:Longitudinal Studies; D008159:Lumbar Vertebrae / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D014430:Twins, Monozygotic
keywords: Disc degeneration; End plate; Lumbar spine; MRI; Pathology; Vertebra