title: Bone marrow lesions are associated with altered trabecular morphometry.
abstract: OBJECTIVE
  Bone marrow lesions (BMLs) are a common magnetic resonance (MR) feature in patients with osteoarthritis, however their pathological basis remains poorly understood and has not been evaluated in vivo. Our aim was to evaluate the trabecular structure associated with the presence and size of BMLs present in the same regions of interest (ROI) using quantitative MR-based trabecular morphometry.
  
  
  METHODS
  158 participants in the Osteoarthritis Initiative (OAI) were imaged with a coronal 3D fast imaging with steady state precession (FISP) sequence for trabecular morphometry in the same session as the OAI 3 T MR knee evaluation. The proximal medial tibial subchondral bone in the central weight-bearing ROI on these knee 3D FISP images were quantitatively evaluated for apparent bone volume fraction, trabecular number, spacing, and thickness. BMLs were also evaluated in the subchondral bone immediately adjacent to the articular cartilage. BML volume was also evaluated within the same trabecular morphometry ROI and semi-quantitatively classified as none, small, or large. Kruskal-Wallis test was used to determine if mean apparent bone volume fraction, trabecular number, spacing, or thickness differed by BML score.
  
  
  RESULTS
  Compared to knees with ROIs containing no BMLs, knees with small or large BMLs had statistically higher apparent bone volume fraction (P < 0.01), trabecular number (P < 0.01), and thickness (P = 0.02), and lower trabecular spacing (P < 0.01).
  
  
  CONCLUSIONS
  Compared to knees with ROIs containing no BMLs, knees with ROIs containing small or large BMLs had higher apparent bone volume fraction, trabecular number and thickness, but lower trabecular spacing. These findings may represent areas of locally increased bone remodeling or compression.
authors.affiliation: Division of Rheumatology, Tufts Medical Center, 800 Washington Street, Boston, MA 02111, USA. jdriban@tuftsmedicalcenter.org
authors.forename: J B
authors.initials: JB
authors.lastname: Driban
authors.forename: A
authors.initials: A
authors.lastname: Tassinari
authors.forename: G H
authors.initials: GH
authors.lastname: Lo
authors.forename: L L
authors.initials: LL
authors.lastname: Price
authors.forename: E
authors.initials: E
authors.lastname: Schneider
authors.forename: J A
authors.initials: JA
authors.lastname: Lynch
authors.forename: C B
authors.initials: CB
authors.lastname: Eaton
authors.forename: T E
authors.initials: TE
authors.lastname: McAlindon
mesh_terms: D000368:Aged; D001853:Bone Marrow / Q000473:pathology*; D002358:Cartilage, Articular / Q000473:pathology*; D003430:Cross-Sectional Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D020370:Osteoarthritis, Knee / Q000473:pathology*; D013977:Tibia / Q000473:pathology*