title: Comparison between magnetic resonance imaging and arthroscopy in the diagnosis of patellar cartilage lesions: a prospective study.
abstract: A blind and prospective study was conducted to assess the accuracy of magnetic resonance imaging (MRI) for diagnosing patellar cartilage lesions. Thirty-three consecutive patients undergoing knee arthroscopy were examined by MRI prior to surgery. Imaging was performed in the axial plane on a 1.5-Tesla unit with spin-echo and gradient-echo T1 and T2 sequences. The MRI and arthroscopic data were compared using a four-grade classification and a patellar map which divided the patellar surface into four quadrants. The overall sensitivity of MRI was 84.7% and the specificity 97.2%. The same pit-fall led to two MRI false positives. A perfect correlation of grading was obtained in 76.5%. When discordance was found, the tendency with MRI was commonly to underestimate the grade of the lesions. The MRI accuracy was high in this study in spite of a high rate of low-grade lesions which are difficult to assess. Related criteria for cartilage assessment with MRI and arthroscopy are suggested for further studies.
authors.affiliation: Hôpital Orthopédique de la Suisse Romande, Lausanne, Switzerland.
authors.forename: J A
authors.initials: JA
authors.lastname: Vallotton
authors.forename: R A
authors.initials: RA
authors.lastname: Meuli
authors.forename: P F
authors.initials: PF
authors.lastname: Leyvraz
authors.forename: M
authors.initials: M
authors.lastname: Landry
mesh_terms: D000293:Adolescent; D000328:Adult; D001182:Arthroscopy / Q000379:methods; D002358:Cartilage, Articular / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000175:diagnosis*; D007719:Knee Joint / Q000473:pathology* / Q000503:physiopathology; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012680:Sensitivity and Specificity