Ligaments are strong bands of tissue that connect one bone to another. The ACL, one of two ligaments that cross in the middle of the knee, connects your thighbone (femur) to your shinbone (tibia) and helps stabilize your knee joint.
Most ACL injuries happen during sports and fitness activities. The ligament may tear when you slow down suddenly to change direction or pivot with your foot firmly planted, twisting or overextending your knee.
But not everyone who tears an ACL requires ACL reconstruction. Sedentary people who forgo sports that involve a lot of quick stops and changes in direction usually recover well with conservative treatments and physical therapy.
Your doctor may recommend ACL reconstruction if:
- You're an athlete and want to continue in your sport, especially if the sport involves jumping, cutting or pivoting
- More than one ligament or the cartilage in your knee is injured
- You're young and active
- The injury is causing your knee to buckle during everyday activities, such as stair climbing