Anterior tibial translocation and ACR

Uncovered posterior horn lateral meniscus and anterior tibial translation. A 32-year-old man who suffered knee injury. Sagittal intermediate-weighted magnetic resonance image of complete anterior cruciate ligament tear patient. The anterior displacement of the tibial translation is measured as the distance between two lines parallel to the picture frame (white lines). At the mid-sagittal plane of lateral femoral condyle, a line is drawn through the most posterior corner of the lateral tibial plateau, and the second line is tangent to the most posterior aspect of the lateral femoral condyle. Anterior tibial translation between 5 and 7 mm is suggestive and over 7 mm is diagnostic of anterior cruciate ligament tear. Note that the lateral meniscus also intersects the tangent to posterior margin of tibia and represents the uncovered posterior horn of lateral meniscus.