title: Hip MRI: Prevalence of articular cartilage defects and labral tears in asymptomatic volunteers. A comparison with a matched population of patients with femoroacetabular impingement.
abstract: To prospectively compare defects of the articular cartilage and labrum in asymptomatic volunteers and in patients with femoroacetabular impingement (FAI) matched for age and gender.
  
  
  
  This cross-sectional study was institutional review board approved. A total of 63 asymptomatic volunteers and 63 patients with symptomatic FAI between 20 and 50 years underwent 1.5 Tesla MRI (coronal T1-weighted, coronal intermediate-weighted fat saturated, transverse oblique true fast imaging with steady-state precession [FISP], sagittal dual echo steady state [DESS] sequence). Two radiologists independently assessed defects of the cartilage and labrum at six positions. Statistics included Mann-Whitney U-test and Spearman's rho.
  
  
  
  A defect of the articular cartilage and/or labrum was present on average in 57% of asymptomatic volunteers, compared with 80% of symptomatic patients (P ≤ 0.028). A total of 14% of volunteers had acetabular cartilage defects, and 6% had femoral cartilage defects, compared with 47% and 30% in symptomatic patients (P ≤ 0.001 and P ≤ 0.003), respectively. Labrum defects were seen in 44% of volunteers versus 61% of patients (P ≤ 0.12). Both cartilage and labral defects were more commonly encountered in male volunteers than in female volunteers, with the largest difference seen for the acetabular cartilage (P ≤ 0.02). In all groups, the majority of cartilage and labrum defects were encountered in the anterosuperior, superior, and posterosuperior position.
  
  
  
  A substantial number of asymptomatic volunteers had labral tears, defects of the acetabular cartilage, and to a lesser degree, defects of the femoral cartilage; our data demonstrate that not all cartilage and labral defects of the hip joint are symptomatic and that a similar predilection for location of defects is found in volunteers and FAI patients.
  
  
  
  2 Technical Efficacy: Stage 3 J. MAGN. RESON. IMAGING 2017;46:440-451.
authors.affiliation: Department of Radiology, Orthopedic University Hospital Balgrist, Zurich, Switzerland.|University of Zurich, Faculty of Medicine, Zurich, Switzerland.
authors.forename: Florian
authors.initials: F
authors.lastname: Tresch
authors.affiliation: Department of Radiology, Orthopedic University Hospital Balgrist, Zurich, Switzerland.|University of Zurich, Faculty of Medicine, Zurich, Switzerland.
authors.forename: Tobias J
authors.initials: TJ
authors.lastname: Dietrich
authors.affiliation: Department of Radiology, Orthopedic University Hospital Balgrist, Zurich, Switzerland.|University of Zurich, Faculty of Medicine, Zurich, Switzerland.
authors.forename: Christian W A
authors.initials: CWA
authors.lastname: Pfirrmann
authors.affiliation: Department of Radiology, Orthopedic University Hospital Balgrist, Zurich, Switzerland.|University of Zurich, Faculty of Medicine, Zurich, Switzerland.
authors.forename: Reto
authors.initials: R
authors.lastname: Sutter
mesh_terms: D000077:Acetabulum / Q000000981:diagnostic imaging* / Q000293:injuries; D000328:Adult; D001182:Arthroscopy; D002358:Cartilage, Articular / Q000000981:diagnostic imaging* / Q000293:injuries; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D057925:Femoracetabular Impingement / Q000000981:diagnostic imaging*; D005269:Femur / Q000000981:diagnostic imaging*; D064368:Healthy Volunteers; D006615:Hip / Q000000981:diagnostic imaging*; D006621:Hip Joint / Q000000981:diagnostic imaging; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011871:Radiology; D015203:Reproducibility of Results; D055815:Young Adult
keywords: cartilage; defects; femoroacetabular impingement; hip; labrum; volunteers