The comparative study of the anterior cruciate ligament in oblique coronal thin anatomical section and MRI

Objective: To compare the normal anatomy of the anterior cruciate ligament (ACL) of fresh frozen cadaveric knee specimen in oblique coronal thin-slice section with oblique coronal magnetic resonance imaging. Methods: One fresh cadaveric knee specimen was scanned with MR T1-weighted spin- echo sequence, then the specimen was frozen and sliced with a band saw along the oblique coronal plane into 1.0-mm-thick sections that corresponded to the MR images, MR images including oblique coronal T1-weighted and T2-weighted images of 50 normal the knee joints were retrospectively reviewed to observe the MR imaging features of the cruciate ligament. Results: Anteromedial and posterolaterai bundles of ACL were clearly depicted on both anatomic slices and MR images. The anteromedial bundles originated from the posteromedial aspect of the lateral femoral condyle, coursing through the lateral intercondylar notch in an anterior, inferior, and medial direction, and inserted on the anteromedial aspect of the intercondylar eminence. The posterolateral bundles originated from the anteromedial aspect of the lateral femoral condyle, passing laterally and inferiorly through the lateral intercondylar notch, and inserted on the posterolateral side of the intercondylar eminence. The full length of ACL of all 50 individuals was showed on MR images. MRI clearly differenitated the anteromedial and posterolateral bundles of ACL and depicted the full length of the bundles, similar to the findings on sectional anatomy. Conclusion: Oblique coronal MR imaging is the best way to demonstrate ACL and should be used for clinically suspected injury of ACL. (authors)