Your Anterior Cruciate Ligament (ACL) crosses from the back of your femur to the front of your tibia. Although interwoven, overlapping fibers make it a strong brace for your knee, the ACL is injured more often than the Posterior Colateral Ligament (PCL) because its smaller and more susceptible to twisting.
Your ACL may be injured when you twist your knee beyond its normal range of motion. A complete tear of your ACL is like the unraveling of rope fibers. A partial tear can also occur. You may injure other parts of your knee at the same time as you injure your ACL
After an ACL injury, your knee more easily buckles, allowing the tibia to shift forward.
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