title: Magnetic resonance mapping of the rim of articular cartilage defects of the patella.
abstract: OBJECTIVE
  Elevated T2-values of articular cartilage are associated with an increase in cartilage water that results from a damaged collagen matrix, and provide a marker for cartilage damage. We used T2 mapping to analyse the rim of cartilage defects that appeared to be intact on the morphological sequences, to determine whether there are early biochemical changes already present.
  
  
  METHODS
  We calculated T2 values for the rim of cartilage defects in 25 patients and compared these values to another area of control cartilage in these patients.
  
  
  RESULTS
  A highly significant increase in T2 values of the deep, superficial, and global layer of the rim versus the control cartilage was measured. ANOVA showed a significant correlation of the defect levels with the T2 values of the deep and global zone of the adjacent cartilage tissue, but not with the superficial zone.
  
  
  CONCLUSIONS
  Although cartilage appears to be intact on morphological sequences, T2 mapping can show a loss of structural anisotropy of collagen and the associated increase in cartilage water that indicates the destruction of the adjacent cartilage. Preoperative information about the degree of damage of the collagen matrix will support decision making for cartilage repair.
authors.affiliation: Department of Orthopaedic Surgery, Medical University of Vienna, Waehringer Gürtel 18-20, 1090, Vienna, Austria, ulrich.koller@meduniwien.ac.at.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Koller
authors.forename: Sebastian
authors.initials: S
authors.lastname: Apprich
authors.forename: Stephan
authors.initials: S
authors.lastname: Domayer
authors.forename: Reinhard
authors.initials: R
authors.lastname: Windhager
authors.forename: Siegfried
authors.initials: S
authors.lastname: Trattnig
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D002358:Cartilage, Articular / Q000378:metabolism / Q000473:pathology*; D003094:Collagen / Q000378:metabolism; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000378:metabolism / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010329:Patella / Q000473:pathology*; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D003094:Collagen