ACL—Current Understanding of ACL Insertion

The femoral insertion of the anterior cruciate ligament (ACL) is in the shape of a crescent, with the lateral intercondylar ridge as its straight anterior border and the posterior articular margin of the lateral femoral condyle as its convex posterior border. After removal of the surface membrane, the configuration of the intraligamentous part of the ACL was a “ribbon-like” ligament. The “double-bundle effect” was created by the twisted flat structure, when the knee was flexed. The flat ACL midsubstance formed a narrow C-shaped bony tibial attachment along the medial tibial spine to the anterior aspect of the anterior root of the lateral meniscus in the area intercondylaris anterior. There were only anteromedial and posteromedial inserting fibers.