RESUMO
OBJECTIVE: The purpose of this study was to compare the diagnostic performance of magnetic resonance imaging with arthroscopy for intra-articular knee conditions. MATERIAL AND METHOD: Between January 2000 and February 2007, 93 patients with medial meniscal tear, lateral meniscal tear, anterior cruciate ligament rupture, and articular cartilage pathology were prospectively assessed. After the physical exam, magnetic resonance imaging studies and arthroscopic surgery of the knee were performed. The sensitivity, specificity, positive and negative predictive values and the diagnostic odds ratio were estimated to compare the magnetic resonance imaging diagnoses with the arthroscopic findings. RESULTS: Fifty-two patients were males and 41 females; mean patient age was 42.6 years (16-68 years). The diagnostic odds ratio was significant for medial meniscal tear, anterior cruciate ligament rupture and the coexistence of both meniscal and ligament lesions. CONCLUSION: The strength of the diagnostic association confirms the usefulness of magnetic resonance imaging for medial meniscal tears, anterior cruciate ligament rupture and the coexistence of both lesions. We do not recommend ordering a routine preoperative magnetic resonance imaging study as a condition for performing knee arthroscopy.