title: Clinical evaluation of T2 values of patellar cartilage in patients with osteoarthritis.
abstract: OBJECTIVE
  The transverse relaxation time constant, T2, of articular cartilage has been proposed as a biomarker for osteoarthritis (OA). Previous studies have not clearly defined the relationship between cartilage T2 values and clinical methods of grading OA or known factors associated with OA. This study compared T2 values of patellar cartilage grouped by radiographic stage of patello-femoral OA and by body mass index (BMI).
  
  
  METHODS
  T2 values of patellar cartilage were calculated for 113 subjects using images acquired on a 1.5 T clinical scanner. Radiographs of the patello-femoral joint were graded for OA grading using the Kellgren-Lawrence scale.
  
  
  RESULTS
  No differences of T2 values were found across the stages of OA (P = 0.25), but the factor of BMI did have a significant effect (P < 0.0001) on T2 value.
  
  
  CONCLUSIONS
  The results indicate the T2 values are not sensitive to changes in radiographic stages of OA. In addition, differences of T2 values with BMI signify structural changes occurring within the patello-femoral joint and that BMI may be considered a factor for a potential increase of T2 values. Future studies comparing different OA grading methods with T2 mapping may highlight the sensitivity of T2 mapping in a clinical setting.
authors.affiliation: Department of Orthopedic Surgery, Mayo Clinic, Biomechanics/Motion Analysis Laboratory, CHN LO-110L, 200 First Street SW, Rochester, MN 55901, USA.
authors.forename: M F
authors.initials: MF
authors.lastname: Koff
authors.forename: K K
authors.initials: KK
authors.lastname: Amrami
authors.forename: K R
authors.initials: KR
authors.lastname: Kaufman
mesh_terms: D000368:Aged; D002358:Cartilage, Articular / Q000473:pathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000145:classification / Q000175:diagnosis*; D010329:Patella / Q000473:pathology*