title: Factors affecting patella cartilage and bone in middle-aged women.
abstract: OBJECTIVE
  To evaluate the effects of age, physical activity, and body mass index (BMI) on patella cartilage volume and defects and bone volume in middle-aged women without knee pain.
  
  
  METHODS
  Magnetic resonance imaging was performed in 176 healthy women, ages 40-67 years, without knee pain to measure patella cartilage and bone volume and patella cartilage defects. The effects of age, physical activity, BMI, smoking, and alcohol were analyzed to determine whether associations existed between these variables and patella cartilage and bone volume and cartilage defects.
  
  
  RESULTS
  Patella cartilage volume decreased with age (P = 0.01) and BMI (P = 0.05) after adjusting for age and patella bone volume. Patella bone volume was positively associated with body height in both the univariate and multivariate models. Cartilage defects in the patellofemoral compartment were present in 36.4% of the study population. Age, weight, and BMI were positively associated with the presence of cartilage defects in the multivariate analysis.
  
  
  CONCLUSIONS
  This study demonstrated that although age is positively associated with both patella bone volume and cartilage defects, it is inversely associated with patella cartilage volume in healthy individuals. Moreover, BMI is inversely associated with both patella cartilage volume and patella bone volume in middle-aged women without knee osteoarthritis. Longitudinal studies will be required to determine whether avoiding a high BMI will reduce the risk of developing patellofemoral osteoarthritis.
authors.affiliation: Monash University Medical School, Alfred Hospital, Prahran, Victoria, Australia.
authors.forename: F S
authors.initials: FS
authors.lastname: Hanna
authors.forename: R J
authors.initials: RJ
authors.lastname: Bell
authors.forename: S R
authors.initials: SR
authors.lastname: Davis
authors.forename: A E
authors.initials: AE
authors.lastname: Wluka
authors.forename: A J
authors.initials: AJ
authors.lastname: Teichtahl
authors.forename: R
authors.initials: R
authors.lastname: O'Sullivan
authors.forename: F M
authors.initials: FM
authors.lastname: Cicuttini
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D001827:Body Height; D015992:Body Mass Index; D002356:Cartilage / Q000473:pathology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008019:Life Style; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009043:Motor Activity; D015999:Multivariate Analysis; D009765:Obesity / Q000453:epidemiology; D020370:Osteoarthritis, Knee / Q000453:epidemiology* / Q000473:pathology*; D010329:Patella / Q000473:pathology*; D012307:Risk Factors; D013977:Tibia / Q000473:pathology*