title: Subchondral bone trabecular integrity predicts and changes concurrently with radiographic and magnetic resonance imaging-determined knee osteoarthritis progression.
abstract: OBJECTIVE
  To evaluate subchondral bone trabecular integrity (BTI) on radiographs as a predictor of knee osteoarthritis (OA) progression.
  
  
  METHODS
  Longitudinal (baseline, 12-month, and 24-month) knee radiographs were available for 60 female subjects with knee OA. OA progression was defined by 12- and 24-month changes in radiographic medial compartment minimal joint space width (JSW) and medial joint space area (JSA), and by medial tibial and femoral cartilage volume on magnetic resonance imaging. BTI of the medial tibial plateau was analyzed by fractal signature analysis using commercially available software. Receiver operating characteristic (ROC) curves for BTI were used to predict a 5% change in OA progression parameters.
  
  
  RESULTS
  Individual terms (linear and quadratic) of baseline BTI of vertical trabeculae predicted knee OA progression based on 12- and 24-month changes in JSA (P < 0.01 for 24 months), 24-month change in tibial (P < 0.05), but not femoral, cartilage volume, and 24-month change in JSW (P = 0.05). ROC curves using both terms of baseline BTI predicted a 5% change in the following OA progression parameters over 24 months with high accuracy, as reflected by the area under the curve measures: JSW 81%, JSA 85%, tibial cartilage volume 75%, and femoral cartilage volume 85%. Change in BTI was also significantly associated (P < 0.05) with concurrent change in JSA over 12 and 24 months and with change in tibial cartilage volume over 24 months.
  
  
  CONCLUSIONS
  BTI predicts structural OA progression as determined by radiographic and MRI outcomes. BTI may therefore be worthy of study as an outcome measure for OA studies and clinical trials.
authors.affiliation: Department of Medicine, Duke University, Durham, NC 27710.
authors.forename: Virginia Byers
authors.initials: VB
authors.lastname: Kraus
authors.affiliation: Biostatistics and Bioinformatics, Duke University, Durham, NC 27710.
authors.forename: Sheng
authors.initials: S
authors.lastname: Feng
authors.affiliation: Biostatistics and Bioinformatics, Duke University, Durham, NC 27710.
authors.forename: ShengChu
authors.initials: S
authors.lastname: Wang
authors.affiliation: Duke Image Analysis Laboratory, Department of Radiology, Duke University, Durham, NC 27710.
authors.forename: Scott
authors.initials: S
authors.lastname: White
authors.affiliation: Duke Image Analysis Laboratory, Department of Radiology, Duke University, Durham, NC 27710.
authors.forename: Maureen
authors.initials: M
authors.lastname: Ainslie
authors.affiliation: Pfizer Global Research and Development, Groton, CT, USA.
authors.forename: Marie-Pierre Hellio Le
authors.initials: MHL
authors.lastname: Graverand
authors.affiliation: Optasia Medical, Manchester, UK and current employee of Mindways Software, Inc.
authors.forename: Alan
authors.initials: A
authors.lastname: Brett
authors.affiliation: Institute of Anatomy & Musculoskeletal Research, Paracelsus Medical University (PMU), Salzburg, Austria & Chondrometrics GmbH, Ainring, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Eckstein
authors.affiliation: New England Baptist Hospital, Boston, MA and Institute of Bone and Joint Research, University of Sydney, Sydney, Australia.
authors.forename: David J
authors.initials: DJ
authors.lastname: Hunter
authors.affiliation: University of California at Davis Medical Center, Sacramento, CA.
authors.forename: Nancy E
authors.initials: NE
authors.lastname: Lane
authors.affiliation: University of Arizona, Tuscon, AZ.
authors.forename: Mihra S
authors.initials: MS
authors.lastname: Taljanovic
authors.affiliation: Northwestern University, Chicago, IL.
authors.forename: Thomas
authors.initials: T
authors.lastname: Schnitzer
authors.affiliation: Duke Image Analysis Laboratory, Department of Radiology, Duke University, Durham, NC 27710.
authors.forename: H Cecil
authors.initials: HC
authors.lastname: Charles
mesh_terms: D000368:Aged; D002358:Cartilage, Articular / Q000000981:diagnostic imaging* / Q000473:pathology; D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging* / Q000473:pathology; D017709:Fractals; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000175:diagnosis*; D012372:ROC Curve; D011859:Radiography; D013977:Tibia / Q000000981:diagnostic imaging* / Q000473:pathology