Value of computerized tomography and nuclear magnetic resonance tomography in preoperative diagnosis of meniscus lesions and ligamentous lesions of the knee joint

In a prospective study, 53 patients with chronic complaints and acute injuries of the knee joint, were evaluated by clinical examination, CT-scanning and magnetic resonance imaging (MRI). Subsequently, arthroscopy or an open surgical procedure was performed. A total of 21 patients suffered from meniscal lesions. There were 17 ruptures of the medial and 4 ruptures of the lateral meniscus. In patients with meniscus ruptures, the sensitivity of both MRI and CT-scan was 86%, whereas the specificity of MRI was slightly lower than that of CT-scan. The accuracy and the predictive value were also slightly lower, although the difference was not significant. Fifteen patients suffered from acute or chronic ligament ruptures. In patients with anterior cruciate ligament (ACL) ruptures, all complete ACL ruptures had correctly been diagnosed by CT and MRI. Two out of four partial ACL ruptures were missed by MRI; only one was missed by CT-scan. Three medial collateral ligament ruptures were documented by MRI and two by CT-scanning. The high negative predictive value of CT and MRI can realize a reduction of the amount of diagnostic arthroscopies.