Reliability of magnetic resonance imaging of the traumatic knee as determined by arthroscopy.

BACKGROUND: Magnetic resonance imaging (MRI) has become an important modality in the assessment of traumatic soft-tissue injury of the knee. METHODS: This prospective study was performed to evaluate the accuracy of MRI used at Wellington Hospital--by comparing the result of the scans of 67 patients with subsequent arthroscopy. RESULTS: The imaging studies provided a diagnostic accuracy of 90% for the medial meniscus, 82% for the lateral meniscus, 94% for the anterior cruciate ligament, and 96% for the posterior cruciate. The sensitivity was 87% for the medial meniscus, only 46% for the lateral meniscus, 92 % for the anterior cruciate, and 80% for the posterior cruciate. The specificity was relatively high at 92%, 91%, 94%, and 97%, respectively.