title: Significance of preradiographic magnetic resonance imaging lesions in persons at increased risk of knee osteoarthritis.
abstract: OBJECTIVE
  Little is known about early knee osteoarthritis (OA). The significance of lesions on magnetic resonance imaging (MRI) in older persons without radiographic OA is unclear. Our objectives were to determine the extent of tissue pathology by MRI and evaluate its significance by testing the following hypotheses: cartilage damage, bone marrow lesions, and meniscal damage are associated with prevalent frequent knee symptoms and incident persistent symptoms; bone marrow lesions and meniscal damage are associated with incident tibiofemoral (TF) cartilage damage; and bone marrow lesions are associated with incident patellofemoral (PF) cartilage damage.
  
  
  METHODS
  In a cohort study of 849 Osteoarthritis Initiative (OAI) participants who had a bilateral Kellgren/Lawrence (K/L) score of 0, we assessed cartilage damage, bone marrow lesions, and meniscal damage using the MRI OA Knee Score, as well as prevalent frequent knee symptoms, incident persistent symptoms, and incident cartilage damage. Multiple logistic regression (one knee per person) was used to evaluate associations between MRI lesions and each of these outcomes.
  
  
  RESULTS
  Of the participants evaluated, 76% had cartilage damage, 61% had bone marrow lesions, 21% had meniscal tears, and 14% had meniscal extrusion. Cartilage damage (any; TF and PF), bone marrow lesions (any; TF and PF), meniscal extrusion, and body mass index (BMI) were associated with prevalent frequent symptoms. Cartilage damage (isolated PF; TF and PF), bone marrow lesions (any; isolated PF; TF and PF), meniscal tears, and BMI were associated with incident persistent symptoms. Hand OA, but no individual lesion type, was associated with incident TF cartilage damage, and bone marrow lesions (any; any PF) with incident PF damage. Having more lesion types was associated with a greater risk of outcomes.
  
  
  CONCLUSIONS
  MRI-detected lesions are not incidental and may represent early disease in persons at increased risk of knee OA.
authors: Northwestern University, Chicago, Illinois.
authors: Leena
authors: L
authors: Sharma
authors: Joan S
authors: JS
authors: Chmiel
authors: Orit
authors: O
authors: Almagor
authors: Dorothy
authors: D
authors: Dunlop
authors: Ali
authors: A
authors: Guermazi
authors: Joan M
authors: JM
authors: Bathon
authors: Charles B
authors: CB
authors: Eaton
authors: Marc C
authors: MC
authors: Hochberg
authors: Rebecca D
authors: RD
authors: Jackson
authors: C Kent
authors: CK
authors: Kwoh
authors: W Jerry
authors: WJ
authors: Mysiw
authors: Michel D
authors: MD
authors: Crema
authors: Frank W
authors: FW
authors: Roemer
authors: Michael C
authors: MC
authors: Nevitt
mesh_terms: D000368:Aged; D001853:Bone Marrow / Q000473:pathology; D002358:Cartilage, Articular / Q000473:pathology; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D015994:Incidence; D007719:Knee Joint / Q000473:pathology*; D016015:Logistic Models; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008592:Menisci, Tibial / Q000473:pathology; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000453:epidemiology* / Q000473:pathology*; D057071:Patellofemoral Joint / Q000473:pathology; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors