title: Does joint alignment affect the T2 values of cartilage in patients with knee osteoarthritis?
abstract: OBJECTIVE
  To assess the relationship between T2 values of femorotibial cartilage and knee alignment in patients with clinical symptoms of medial osteoarthritis (OA).
  
  
  METHODS
  Twenty-four patients (mean age +/- standard deviation, 62.5 +/- 9.9 years) with clinical symptoms of medial knee OA, 12 with varus and 12 with valgus alignment of the femorotibial joint, were investigated on 3T MR using a 2D multi-echo spin echo (MESE) sequence for T2 mapping. Analysis of covariance, Spearman correlation coefficients, exact Mann-Whitney tests, and Fisher's exact tests were used for statistical analysis.
  
  
  RESULTS
  Overall the T2 values of cartilage in the medial compartment (median +/- interquartile-range, 49.44 +/- 6.58) were significantly higher (P = 0.0043) than those in the lateral compartment (47.15 +/- 6.87). Patients with varus alignment (50.83 +/- 6.30 ms) had significantly higher T2 values of cartilage (P < 0.0001) than patients with valgus alignment (46.20 +/- 6.00 ms). No statistically significant association between the T2 values of cartilage (in either location) and the Kellgren Lawrence score was found in the varus or in the valgus group.
  
  
  CONCLUSIONS
  T2 measurements were increased in medial knee OA patients with varus alignment, adding support to the theory of an association of OA and joint alignment.
authors.affiliation: Department of Radiology, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria. klaus.friedrich@meduniwien.ac.at
authors.forename: Klaus M
authors.initials: KM
authors.lastname: Friedrich
authors.forename: Timothy
authors.initials: T
authors.lastname: Shepard
authors.forename: Gregory
authors.initials: G
authors.lastname: Chang
authors.forename: Ligong
authors.initials: L
authors.lastname: Wang
authors.forename: James S
authors.initials: JS
authors.lastname: Babb
authors.forename: Mark
authors.initials: M
authors.lastname: Schweitzer
authors.forename: Ravinder
authors.initials: R
authors.lastname: Regatte
mesh_terms: D002358:Cartilage, Articular / Q000473:pathology*; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000209:etiology* / Q000473:pathology*; D007719:Knee Joint / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000150:complications* / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity