title: Association between MRI-detected knee joint regional effusion-synovitis and structural changes in older adults: a cohort study.
abstract: OBJECTIVE
  To describe the cross-sectional and longitudinal associations between knee regional effusion-synovitis and structural changes in older adults.
  
  
  METHODS
  A total of 977 subjects were randomly selected from the local community (mean 62 years, 50% female) at baseline and 404 were followed up 2.6 years later. T2-weighted MRI was used to assess knee effusion-synovitis in four subregions: suprapatellar pouch, central portion, posterior femoral recess and subpopliteal recess. Knee cartilage defects, cartilage volume and bone marrow lesions (BMLs) were measured using MRI at baseline and follow-up.
  
  
  RESULTS
  Cross-sectionally, effusion-synovitis in most subregions was significantly associated with a higher risk of cartilage defects, BMLs and reduced cartilage volume. Longitudinally, suprapatellar pouch effusion-synovitis at baseline predicted an increase in cartilage defects (p<0.01), loss of cartilage volume (p=0.04) and an increase in BMLs (p=0.02) in multivariable analyses. The significant associations of effusion-synovitis with cartilage volume and BMLs disappeared after adjustment for cartilage defects. Effusion-synovitis in whole knee joint (p<0.01) and subpopliteal recess (p<0.05) was consistently associated with longitudinal changes in cartilage defects but not in cartilage volume and BMLs.
  
  
  CONCLUSIONS
  There are independent associations between knee joint effusion-synovitis and knee cartilage defects in both cross-sectional and longitudinal analyses, suggesting a potential causal relationship. The associations of effusion-synovitis with BMLs and cartilage volume were largely dependent on cartilage defects, suggesting potential causal pathways.
authors.affiliation: Menzies Research Institute Tasmania, University of Tasmania, Hobart, Tasmania, Australia.
authors.forename: Xia
authors.initials: X
authors.lastname: Wang
authors.affiliation: Menzies Research Institute Tasmania, University of Tasmania, Hobart, Tasmania, Australia.
authors.forename: Leigh
authors.initials: L
authors.lastname: Blizzard
authors.affiliation: Department of Radiology, Royal Hobart Hospital, Hobart, Tasmania, Australia.
authors.forename: Andrew
authors.initials: A
authors.lastname: Halliday
authors.affiliation: Menzies Research Institute Tasmania, University of Tasmania, Hobart, Tasmania, Australia.
authors.forename: Weiyu
authors.initials: W
authors.lastname: Han
authors.affiliation: Menzies Research Institute Tasmania, University of Tasmania, Hobart, Tasmania, Australia.
authors.forename: Xingzhong
authors.initials: X
authors.lastname: Jin
authors.affiliation: Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria, Australia.
authors.forename: Flavia
authors.initials: F
authors.lastname: Cicuttini
authors.affiliation: Menzies Research Institute Tasmania, University of Tasmania, Hobart, Tasmania, Australia.
authors.forename: Graeme
authors.initials: G
authors.lastname: Jones
authors.affiliation: Menzies Research Institute Tasmania, University of Tasmania, Hobart, Tasmania, Australia Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria, Australia Arthritis Research Institute, 1st Affiliated Hospital, Anhui Medical University, Hefei, Anhui, China.
authors.forename: Changhai
authors.initials: C
authors.lastname: Ding
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001853:Bone Marrow / Q000473:pathology*; D002358:Cartilage, Articular / Q000473:pathology*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D018450:Disease Progression; D005122:Exudates and Transudates; D005260:Female; D006801:Humans; D006833:Hydrarthrosis / Q000473:pathology*; D007719:Knee Joint / Q000473:pathology*; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D020370:Osteoarthritis, Knee / Q000473:pathology*; D011446:Prospective Studies; D013585:Synovitis / Q000473:pathology*
keywords: Inflammation; Knee Osteoarthritis; Synovitis