The Validation of Clinical Examination and MRI as a Diagnostic Tool for Cruciate Ligaments and Meniscus Injuries of the Knee Against Diagnostic Arthroscopy.

BACKGROUND: This study was conducted to compare the accuracy of MRI findings and clinical examination of ligamentous and meniscal injuries of the knee, taking arthroscopy as a standard diagnostic tool in knee injuries.  Methods: All patients with knee injuries attending the outpatient department or emergency of our hospital underwent clinical examination. Out of them, 60 patients with knee injuries were subjected to clinical examination, MRI, and then arthroscopy. The findings of these diagnostic tools in respect to the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), and meniscus injuries were validated, compared, and analyzed using various statistical tools. The accuracy, sensitivity, negative predictive value (NPV), positive predictive value (PPV), and specificity were calculated and an agreement between various tests was established using kappa statistics.

RESULTS: The accuracy of clinical examination in our study was 88% for ACL tears, 85% for meniscal tears, and 100% for PCL tears. The kappa measure of agreement between arthroscopy and clinical finding and MRI for ACL was 0.610 and 0.698, respectively, which was statistically significant. MRI (98.1) was found to be a more sensitive test for detecting ACL injury than clinical examination (90.4%) resulting in higher diagnostic accuracy (98.3%), while diagnostic accuracy of clinical examination and MRI was found to be 100% for PCL injuries. Hence, MRI is an excellent screening tool for ligamentous and meniscal injuries of the knee joint. We can avoid diagnostic arthroscopy in patients with knee injuries having equivocal clinical and MRI examinations and can proceed for therapeutic arthroscopy to deal with such injuries.  Conclusions: For the assessment of ligamentous and meniscal injuries, MRI is an accurate and noninvasive modality. It can be used as a first-line investigation but arthroscopy remains the gold standard.