title: Diagnostic accuracy of 3.0 Tesla magnetic resonance imaging for the detection of articular cartilage lesions of the talus.
abstract: BACKGROUND
  Talar chondral defects can be a source of persistent ankle pain and disability. If untreated, there is an increased risk of osteoarthritis. The purpose of our study was to determine diagnostic accuracy of 3T MRI in detecting Outerbridge grades 3 and 4 articular cartilage lesions of the talus in a clinical setting, utilizing a standardized clinical MRI protocol.
  
  
  METHODS
  Patients who had a 3T ankle MRI and subsequent ankle surgery, by a single surgeon, were included in this study. MRI exams were performed 180 days or less before surgery. Seventy-nine ankles in 78 patients (mean age of 42.3 years) were included in this study. Mean body mass index was 26.3. A standard clinical MRI exam was performed on a 3T MRI scanner. Mean days from MRI to surgery was 39 days. All MRI exams were read and findings recorded by a musculoskeletal radiologist. Arthroscopic examination was performed by a single orthopaedic surgeon. Detailed arthroscopic findings and demographic data were collected prospectively and stored in a data registry. Of the 78 patients, 31 (39.2%) reported previous ankle surgery. Pain was the primary reason for seeking medical attention as reported by 95% of patients, followed by instability in 44% and loss of function with 42%.
  
  
  RESULTS
  Prevalence of Outerbridge grade 3 and 4 talar articular cartilage defects identified at arthroscopy was 17.7%. The 3T MRI demonstrated a sensitivity of 0.714, specificity of 0.738, positive predictive value of 0.370, and negative predictive value of 0.923.
  
  
  CONCLUSIONS
  Sensitivity and specificity levels were acceptable for detection of grades 3 and 4 articular cartilage defects of the talar dome using 3T MRI. The high negative predictive value may be beneficial in preoperative planning. While these values are acceptable, a high index of suspicion should be maintained in the appropriate clinical setting.
authors.affiliation: The Steadman Philippon Research Institute, Vail, CO, USA.
authors.forename: Coley C
authors.initials: CC
authors.lastname: Gatlin
authors.affiliation: The Steadman Philippon Research Institute, Vail, CO, USA Lauren.Matheny@sprivail.org.
authors.forename: Lauren M
authors.initials: LM
authors.lastname: Matheny
authors.affiliation: The Steadman Philippon Research Institute, Vail, CO, USA.
authors.forename: Charles P
authors.initials: CP
authors.lastname: Ho
authors.affiliation: The Steadman Philippon Research Institute, Vail, CO, USA.
authors.forename: Nicholas S
authors.initials: NS
authors.lastname: Johnson
authors.affiliation: The Steadman Philippon Research Institute, Vail, CO, USA.
authors.forename: Thomas O
authors.initials: TO
authors.lastname: Clanton
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001182:Arthroscopy; D002357:Cartilage Diseases / Q000175:diagnosis*; D002358:Cartilage, Articular / Q000473:pathology*; D005188:False Negative Reactions; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D013628:Talus / Q000473:pathology*; D055815:Young Adult
keywords: 3 Tesla MRI; magnetic resonance imaging; negative predictive value; osteoarthritis; positive predictive value; sensitivity; specificity; talar cartilage