title: Prevalence of pathologic findings in asymptomatic knees of marathon runners before and after a competition in comparison with physically active subjects-a 3.0 T magnetic resonance imaging study.
abstract: OBJECTIVE
  To determine the prevalence of pathologic findings in asymptomatic knees of marathon runners before and after a competition in comparison with physically active subjects. To compare the diagnostic performance of cartilage-dedicated magnetic resonance imaging (MRI) sequences at 3.0 T.
  
  
  METHODS
  Ten marathon runners underwent 3.0 T MRI 2-3 days before and after competition. Twelve physically active asymptomatic subjects not performing long-distance running were examined as controls. Pathologic condition was assessed with the whole-organ magnetic resonance imaging score (WORMS). Cartilage abnormalities and bone marrow edema pattern (BMEP) were quantified. Visualization of cartilage pathology was assessed with intermediate-weighted fast spin-echo (IM-w FSE), fast imaging employing steady-state acquisition (FIESTA) and T1-weighted three-dimensional (3D) high-spatial-resolution volumetric fat-suppressed spoiled gradient-echo (SPGR) MRI sequences.
  
  
  RESULTS
  Eight of ten marathon runners and 7/12 controls showed knee abnormality. Slightly more and larger cartilage abnormalities, and BMEP, in marathon runners yielded higher but not significantly different WORMS (P > 0.05) than in controls. Running a single marathon did not alter MR findings substantially. Cartilage abnormalities were best visualized with IM-w FSE images (P < 0.05).
  
  
  CONCLUSIONS
  A high prevalence of knee abnormalities was found in marathon runners and also in active subjects participating in other recreational sports. IM-w FSE sequences delineated more cartilage MR imaging abnormalities than did FIESTA and SPGR sequences.
authors.affiliation: Musculoskeletal and Quantitative Imaging Group, Department of Radiology, University of California, San Francisco, 185 Berry Street, Suite 350, San Francisco, CA 94107-0946, USA. Robert.Stahl@radiology.ucsf.edu
authors.forename: Robert
authors.initials: R
authors.lastname: Stahl
authors.forename: Anthony
authors.initials: A
authors.lastname: Luke
authors.forename: C Benjamin
authors.initials: CB
authors.lastname: Ma
authors.forename: Roland
authors.initials: R
authors.lastname: Krug
authors.forename: Lynne
authors.initials: L
authors.lastname: Steinbach
authors.forename: Sharmila
authors.initials: S
authors.lastname: Majumdar
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Link
mesh_terms: D000328:Adult; D012090:Cumulative Trauma Disorders / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000473:pathology*; D007719:Knee Joint / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008592:Menisci, Tibial / Q000473:pathology*; D009043:Motor Activity; D012420:Running / Q000293:injuries*; D000070600:Tibial Meniscus Injuries