title: Glenohumeral articular cartilage lesions: prospective comparison of non-contrast magnetic resonance imaging and findings at arthroscopy.
abstract: OBJECTIVE
  The purpose of this study was to assess the diagnostic sensitivity, specificity, accuracy, negative predictive value (NPV), positive predictive value (PPV), and test-retest reliability of magnetic resonance imaging (MRI) for detecting cartilage abnormalities of the glenohumeral joint in comparison with the gold standard of diagnostic arthroscopy.
  
  
  METHODS
  Forty-four patients with a preoperative non-contrast MRI study of their affected shoulder underwent arthroscopy by one surgeon for rotator cuff tendinopathy from 2009 to 2010. Articular cartilage defects were prospectively recorded and graded according to the International Cartilage Repair Society classification system at the time of arthroscopy. One year after surgery, the preoperative MRI were reviewed by a board-certified radiologist and the treating surgeon for articular cartilage defects of both the humeral head and the glenoid. Sensitivity, specificity, accuracy, and test-retest reliability were calculated.
  
  
  RESULTS
  At arthroscopy, 43% of the shoulders were found to have articular cartilage defects. When the readers' findings were combined, the sensitivity of detecting humeral lesions on MRI was 32%; specificity, 80%; accuracy, 63%; PPV, 57%; and NPV, 66%. The sensitivity of detecting glenoid lesions was 31%; specificity, 86%; accuracy, 76%; PPV, 33%; and NPV, 85%.
  
  
  CONCLUSIONS
  This study finds that the overall accuracy of MRI in detecting articular cartilage damage in patients with the clinical diagnosis of subacromial pathology is moderate.
  
  
  METHODS
  Level II, development of diagnostic criteria based on consecutive patients with universally applied reference "gold" standard.
authors.affiliation: Department of Orthopedics, Mount Nittany Medical Center, State College, Pennsylvania 16803, USA. bas195@hotmail.com
authors.forename: Brian A
authors.initials: BA
authors.lastname: Spencer
authors.forename: Carol A
authors.initials: CA
authors.lastname: Dolinskas
authors.forename: Peter A
authors.initials: PA
authors.lastname: Seymour
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Thomas
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Abboud
mesh_terms: D000328:Adult; D000368:Aged; D001182:Arthroscopy; D002357:Cartilage Diseases / Q000175:diagnosis* / Q000473:pathology; D002358:Cartilage, Articular; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results; D017006:Rotator Cuff; D012680:Sensitivity and Specificity; D012785:Shoulder Joint