Anterior positioning of tibia during motion after anterior cruciate ligament injury

The mechanism of the anterior positioning of tibia is qualitatively similar in the normal and the injured knee, but that position is obtained much further forward in the ACL deficient knee. Quadriceps and gastrocnemius muscles seem to work synergistically to stabilize the knee by maintaining the anterior position of tibia during weight-bearing motion. The role of hamstrings to restrict anterior translation is questioned.