title: The intervertebral disc, the endplates and the vertebral bone marrow as a unit in the process of degeneration.
abstract: OBJECTIVE
  The association of disc degeneration (DD) and vertebral endplate degeneration (EPD) is still not well understood. This study aimed to find segmental predictive risk factors for DD and EPD and to illuminate associations of the disc, endplate and bone marrow changes in the process of degeneration.
  
  
  METHODS
  After institutional review board approval, 450 lumbar levels, followed up with MRI for at least 4 years, were retrospectively graded for DD according to Pfirrmann (PFG), for EPD according to the endplate score (EPS) and according to the presence, extension and type of Modic changes (MC). Clustered logistic regression and multivariate analysis was applied in nested, matched case-control subgroups to evaluate potential local risk factors for progression.
  
  
  RESULTS
  An EPS score of  ≥4 was identified as an independent risk factor for progression of DD (OR = 2.32, 95%CI:1.07-5.01,p = 0.03) and MC (OR = 5.49,95%CI:2.30-13.10,p < 0.001). Progression of DD was significantly accompanied by progression or evolution of MC (OR = 12.25,95%CI:1.49-100.6,p = 0.02) and with progression of EPS (OR = 1.71, 95%CI:1.00-1.05, p = 0.01). Once advanced DD has occurred, it becomes a risk factor for progression in EPS (OR = 2.24,95%CI:1.23-4.12,p < 0.01).
  
  
  CONCLUSIONS
  The degenerative processes in the disc, endplate and bone marrow are highly associated. An EPS ≥ 4 is an independent risk factor for DD and MC progression in a population with low back pain.
  
  
  CONCLUSIONS
  • The degenerative processes in the disc, endplate and bone marrow are associated. • An endplate score ≥4 is a risk factor for DD and MC progression. • Modic changes are last to occur in the development of segmental intervertebral degeneration. • A new segmental grading system is suggested.
authors.affiliation: MRI, Radiology Department, Hospital for Special Surgery, New York, NY, USA. nadja.farshad@usz.ch.|Institute of Diagnostic and Interventional Radiology, University Hospital of Zurich, Raemistrasse 100, Zurich, 8091, Switzerland. nadja.farshad@usz.ch.
authors.forename: Nadja A
authors.initials: NA
authors.lastname: Farshad-Amacker
authors.affiliation: Spine Surgery, Hospital for Special Surgery, New York, NY, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Hughes
authors.affiliation: Spinal Imaging, Hospital for Special Surgery, New York, NY, USA.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Herzog
authors.affiliation: Departement of Biostatistics, Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland.
authors.forename: Burkhardt
authors.initials: B
authors.lastname: Seifert
authors.affiliation: Spine Division, Balgrist University Hospital, Forchstrasse 340, Zurich, 8008, Switzerland.
authors.forename: Mazda
authors.initials: M
authors.lastname: Farshad
mesh_terms: D001855:Bone Marrow Diseases / Q000473:pathology*; D016022:Case-Control Studies; D018450:Disease Progression; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000473:pathology; D055959:Intervertebral Disc Degeneration / Q000473:pathology*; D017116:Low Back Pain / Q000209:etiology / Q000473:pathology; D008159:Lumbar Vertebrae / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged
keywords: Endplate changes; Intervertebral disc; Segmental degeneration; Spine degeneration; Vertebral bone marrow