Torn ACL: FAQ
Mar 16, 2019 Cedars-Sinai Staff
You're playing pickup basketball and decide to fake out the person guarding you. You pivot to change directions—and suddenly your knee buckles and screams out in pain.
You may have torn your anterior cruciate ligament (ACL), the stabilizing ligament in your knee that connects your thighbone to your shinbone.
Injury prevention should be more of a focus than how to deal with it after it happens.
Q: What usually causes an ACL tear?
Dr. Carlos Uquillas: Non-contact pivoting injuries are the most common ACL injuries.
It's not that someone bumps into you or you get tackled the wrong way—it's that your body is moving in one direction, you plant your foot, you try to turn, and the ACL tears.
Q: Can overuse lead to an ACL tear?
Dr. Uquillas: With an ACL tear, it's usually not an issue with the ligament itself that causes the injury—it's an issue of muscles getting fatigued and you losing balance and control over your body.
Without these muscles supporting the knee properly, the ligament is more likely to tear when stressed. That's why it's important to keep your strength through the legs, torso, hips, and trunk for stabilization.
Q: What are the symptoms of a torn ACL?
Dr. Uquillas: Some patients hear a pop when they first injure the ACL. There can be a lot of pain, and sometimes it's hard to put weight on your leg.
If you're unsure whether you seriously injured your knee, keep an eye on the swelling over the first few days after hurting it. Significant swelling that takes days to go away is not normal and should send you to your doctor or the hospital.