The value of MRI in the daily diagnosis of meniscal lesions

Introduction: We investigated the value of Magnetic Resonance Imaging compa red to the clinical examination for meniscal lesions. Material and methods: From 1991 to 1995 we did arthroscopic evaluation at 8 24 patients with the diagnose "meniscal lesion". 73 of them had an MRI-exam ination elsewhere before surgery; Results:During arthroscopy we found 473 lesions of the medial meniscus and 160 of the lateral meniscus. The MRI-examination had an accuracy of 70% for the medial meniscus (sensitivity,79%, specifity 63%,positive predictive va lue 64%, negative predictive value 78%) and 78% for the lateral meniscus (s ensitivity 50%, specifity 86%, positive predictive value 50%, negative pred ictive value 86%). The clinical examination had an accuracy of 73% for the medial meniscus (sensitivity 98%, specifity 39%, positive predictive value 69%, negative predictive value 88%) and 87% for the lateral meniscus (sensi tivity 67%, specifity 92%,positive predictive value 65%,negative predictive value 93%). Conclusions: We conclude, that by an experienced examiner a meniscal lesion can be diagnosed adequately by clinical examination alone. The different r adiologists who did the MRI examination in our study belong to different ou tward departments and used different apparatus:with sometimes insufficient quality of the pictures. Therefore the sensitivity and specifity of the MRI for meniscal lesions is:markedly lower than in other studies of department s where a close cooperation between the radiologist and the orthopedic surg eon is performed.