title: End plate disproportion and degenerative disc disease: a case-control study.
abstract: METHODS
  Case-control.
  
  
  OBJECTIVE
  To determine whether a disproportion between two neighboring vertebral end plates is associated with degenerative disc disease.
  
  
  BACKGROUND
  Recently, it has been suggested that disproportion of the end plates of two adjacent vertebrae may increase the risk of disc herniation.
  
  
  METHODS
  Magnetic resonance (MR) images (n=160) with evidence of grades I-II lumbar degenerative disc disease (modified Pfirrmann's classification) and normal MR images of the lumbar region (n=160) were reviewed. On midsagittal sections, the difference of anteroposterior diameter of upper and lower end plates neighboring a degenerated (in the case group) or normal (in the control group) intervertebral disc was calculated (difference of end plates [DEP]).
  
  
  RESULTS
  Mean DEP was significantly higher in the case group at the L5-S1 level (2.73±0.23 mm vs. 2.21±0.12 mm, p=0.03). Differences were not statistically significant at L1-L2 (1.31±0.13 mm in the cases vs. 1.28±0.08 mm in the controls, p=0.78), L2-L3 (1.45±0.12 mm in the cases vs. 1.37±0.08 mm in the controls, p=0.58), L3-L4 (1.52±0.13 mm in the cases vs. 1.49±0.10 mm in the controls, p=0.88), and L4-L5 (2.15±0.21 mm in the cases vs. 2.04±0.20 mm in the controls, p=0.31) levels. The difference at the L5-S1 level did not remain significant after adjusting for body mass index (BMI), which was significantly higher in the patients.
  
  
  CONCLUSIONS
  End plate disproportion may be a significant, BMI-dependent risk factor for lumbar degenerative disc disease.
authors.affiliation: Department of Radiology and Neuroscience Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Masoud
authors.initials: M
authors.lastname: Poureisa
authors.affiliation: Department of Radiology and Neuroscience Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Mohammad Hossein
authors.initials: MH
authors.lastname: Daghighi
authors.affiliation: Department of Radiology and Neuroscience Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Sepideh
authors.initials: S
authors.lastname: Mesbahi
authors.affiliation: Department of Radiology and Nuclear Medicine, Keck Scholl of Medicine, University of Southern California, Los Angeles, CA, USA.
authors.forename: Amir
authors.initials: A
authors.lastname: Hagigi
authors.affiliation: Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Daniel F
authors.initials: DF
authors.lastname: Fouladi
keywords: Anatomy; Intervertebral disc degeneration; Vertebra