Diagnostics of degenerative meniscal tears at 3-Tesla MRI compared to arthroscopy as reference standard.

ABSTRACT

INTRODUCTION: The goal of this study was to evaluate the diagnostic performance of 3-Tesla MRI for the assessment of degenerative meniscal tears in clinical practice. MATERIALS AND METHODS: In patients with chronic knee pain, a negative history of acute trauma and a mean age of 52 years, 3-Tesla MRI were performed a few days prior to arthroscopy. In 86 menisci, diagnostic values of 3-Tesla MRI for the detection of degenerative tears were evaluated using arthroscopy as reference standard. The MRI classification, for meniscus diagnostics, described by Crues was used. RESULTS: At arthroscopy, all tears identified (19 horizontal, 7 complex, 3 radial) were degenerative as confirmed by histological examination. MRI grade II lesions had a prevalence of 24% and a rate of 24% of missed tears, whereas grade I lesions were not associated with a torn meniscus at arthroscopy. For meniscal tears, (grade III) sensitivity and specificity of 3-Telsa MRI was 79 and 95% for both menisci, 86 and 100% for the medial meniscus, and 57 and 92% for the lateral meniscus. The best diagnostic performance was found for complex tears, horizontal tears showed relatively good results, poor results were documented for radial tears. CONCLUSION: For the medial meniscus, where horizontal and complex tears were more prevalent, 3-Tesla MRI shows a higher accuracy than for the lateral meniscus. Particularly with regard to the medial meniscus, 3-Tesla MRI could be effectively used when a degenerative tear is suspected. Nevertheless, in regard to a remarkable number of false positive and false negative findings the diagnostic value of a 3-Tesla MRI investigation should not be overestimated.