ACL injury

The ACL inserts on the tibial spine, inside the knee joint. The tibial tuberosity is the insertion for the quadriceps tendon, outside the knee joint. Tenderness would not be expected over the tibial tuberosity after an ACL injury. There may be associated severe collateral ligament damage, resulting in laxity and tenderness over the medial collateral ligament, although  this is not always present.

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