title: Factors associated with hip cartilage volume measured by magnetic resonance imaging: the Tasmanian Older Adult Cohort Study.
abstract: OBJECTIVE
  To compare associations between anthropometric and lifestyle factors and femoral head cartilage volume/thickness and radiographic features of osteoarthritis (OA) and to provide evidence of construct validity for magnetic resonance imaging (MRI) assessment of femoral cartilage volume and thickness.
  
  
  METHODS
  We studied a cross-sectional sample of 151 randomly selected subjects (79 men, 72 women; mean age 63 years) from the Tasmanian Older Adult Cohort Study. A sagittal T1-weighted fat-suppression MRI scan of the right hip was performed to determine femoral head cartilage volume, cartilage thickness, and size. An anteroposterior radiograph of the pelvis with weight bearing was performed and scored for radiographic evidence of OA in the right hip. Other factors measured were height, weight, leg strength, serum vitamin D levels, and bone mineral density.
  
  
  RESULTS
  Hip cartilage volume was significantly associated with female sex, body mass index, and femoral head size, whereas hip cartilage thickness was significantly associated only with the size of the femoral head. Only female sex was significantly associated with the total radiographic OA score and the joint space narrowing (JSN) score, but not the osteophyte score. Radiographic JSN of the hip, especially axial JSN (but not osteophytes), was significantly correlated with hip cartilage volume and thickness.
  
  
  CONCLUSIONS
  Femoral head cartilage volume and thickness have modest but significant construct validity when correlated with radiographic findings. Furthermore, the generally stronger associations with volume compared with radiographic OA suggest that MRI may be superior at identifying risk factors for hip OA.
authors.affiliation: University of Tasmania, Hobart, Tasmania, Australia.
authors.forename: Guangju
authors.initials: G
authors.lastname: Zhai
authors.forename: Flavia
authors.initials: F
authors.lastname: Cicuttini
authors.forename: Velandai
authors.initials: V
authors.lastname: Srikanth
authors.forename: Helen
authors.initials: H
authors.lastname: Cooley
authors.forename: Changhai
authors.initials: C
authors.lastname: Ding
authors.forename: Graeme
authors.initials: G
authors.lastname: Jones
mesh_terms: D000368:Aged; D002358:Cartilage, Articular / Q000473:pathology*; D003430:Cross-Sectional Studies; D005260:Female; D005270:Femur Head / Q000473:pathology*; D006621:Hip Joint / Q000473:pathology*; D006801:Humans; D008019:Life Style; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000175:diagnosis* / Q000453:epidemiology; D012737:Sex Factors; D013648:Tasmania / Q000453:epidemiology