Diagnostic accuracy of MRI knee in reference to arthroscopy in meniscal and anterior cruciate ligament injuries

Objective

Data regarding the diagnostic accuracy of Magnetic Resonance Imaging (MRI) are contradictory. The aim of this study was to find the accuracy of MRI knee against arthroscopy, in cases of meniscus and Anterior Cruciate Ligament (ACL) injuries. To the best of our knowledge, this is the largest Indian study comparing MRI knee with arthroscopy comprehensively.

Subjects and methods

210 patients with knee injury who underwent both MRI knee and arthroscopy and either investigation showing ACL or meniscal tear were studied. MRI findings were correlated with arthroscopic findings, considering arthroscopy as the gold standard.

Results

The sensitivity, specificity and accuracy of MRI in reference to arthroscopy for ACL tear was 97.46%, 90.38% and 95.71%, respectively; for Medial Meniscus (MM) tear was 95.69%, 94.87% and 95.23%, respectively; and for Lateral Meniscus (LM) tear was 86.04%, 97.01%, 88.09%, 96.42% and 94.76%, respectively. In ACL tear, mid substance tear was the most common site (66.03%) and discontinuity of ACL fibres was the most common pattern (42.8%). In meniscal tears, posterior horn was the most common site and vertical tears was the most common pattern.

Conclusion

MRI is an excellent noninvasive imaging modality which can accurately detect and characterize various ligament tears of the knee joint.