Anatomical Study of the Femoral and Tibial Insertions of the Anteromedial and Posterolateral Bundles of Human Anterior Cruciate Ligament

BACKGROUND: Recently, anatomical anterior cruciate ligament reconstruction with 2-bundle reconstruction has been proposed. Few previous publications have mentioned anatomical measurements of the insertions of these bundles. PURPOSE: To determine the precise anatomical measurements of the femoral and tibial insertions for anteromedial and posterolateral bundles of anterior cruciate ligament grafts. STUDY DESIGN: Descriptive laboratory study. METHODS: Thirty-two femurs and 31 tibias were selected. The anterior cruciate ligament was divided into anteromedial and posterolateral bundles to the insertion footprint. Six measurements of the femoral insertion and 4 measurements of the tibial insertion were examined. Locations of the femoral insertions were examined using lateral radiographs of the femur. RESULTS: The distance between the center of the femoral insertions of the anteromedial and posterolateral bundles and the posterior margin of the lateral femoral condyle averaged 7.6 and 7.0 mm, respectively. The distance between the center of the femoral insertions of the anteromedial and posterolateral bundles to the intercondylar roof averaged 4.1 and 11.3 mm, respectively. The sagittal distance between the center of the tibial insertions of the anteromedial and posterolateral bundles from the anterior margin of the tibial articular cartilage averaged 13.0 and 14.7 mm, respectively. The distance from the lateral margin of the articular cartilage of the tibial plateau to the center of the tibial insertions of the anteromedial and posterolateral bundles averaged 44.2% and 52.4% of the total widest width of the tibial plateau, respectively. On the lateral radiograph of femoral condyles, the center of the anteromedial bundle was located at 31.9% from the posterior margin of the femoral condyle and 26.9% from the roof, and that of the posterolateral bundle was located at 39.8% from the posterior margin of the femoral condyle and 53.2% from the roof. CLINICAL RELEVANCE: It is important to know the precise anatomy of anterior cruciate ligament bundles when performing reconstruction and to evaluate anterior cruciate ligament reconstruction surgery on an anatomical basis.