|When you twist your knee or fall on it, you can tear a stabilizing ligament that connects your thighbone to the shinbone. The anterior cruciate ligament (ACL) helps to stabilize the knee by preventing the leg bone (tibia) from sliding forward beneath the thigh bone (femur) during twisting and pivoting movements. When it’s torn, the ACL unravels like a braided rope and does not heal on its own. Fortunately, reconstruction surgery can help many people recover their full function after an ACL tear.|
Ligaments are tough, non-stretchable fibers that hold your bones together. The cruciate ligaments in your knee joints crisscross to give you stability on your feet. The ACL runs from the front of the tibia to the back of the femur. People often tear the ACL by changing direction rapidly, slowing down from running or landing from a jump. Young people (age 15 to 25 years old) who participate in basketball and other sports that require pivoting are especially vulnerable. Athletes who wear shoes with cleats and skiers are also prime candidates. Direct contact, such as in a football tackle, can tear the ligament as well.
Studies show that teenage girls and young women are more likely to experience an ACL tear than boys and men in the same sport. For example, the incidence of ACL injuries among female basketball players is twice that for male players. Female soccer players have four times as many injuries as their male counterparts.
You might hear a popping noise when your ACL tears and feel immediate pain. Your knee gives out and soon begins to hurt and swell. First aid treatment includes rest, ice, compression and elevation (RICE) plus a brace to immobilize the knee, crutches and pain relievers. Get to your doctor right away so that your condition can be evaluated.
Your doctor may conduct physical tests and take X-rays to determine the extent of damage to your ACL. A complete tear will require reconstruction surgery. Your doctor replaces the damaged ACL with strong, healthy tissue taken from another area near your knee. A strip of tendon from under your kneecap (patellar tendon) or hamstring may be used. Your doctor threads the tissue through the inside of your knee joint and secures the ends to your thighbone and shinbone.
In a few cases when the ACL is torn cleanly from the bone it can be repaired. Less active people may be treated non-surgically with a program of muscle strengthening.
Successful ACL reconstruction surgery tightens your knee and restores its stability. It also helps you avoid further injury and get back to playing sports. In the U.S., doctors see more than 95,000 ACL tears each year and perform about 50,000 ligament reconstructions. The surgeries are successful about 90 percent of the time.
After ACL reconstruction, you’ll need to do rehabilitation exercises to gradually return your knee to full flexibility and stability. Building strength in your thigh and calf muscles helps support the reconstructed structure. You may need to use a knee brace for awhile and will probably have to stay out of sports for about one year after the surgery.
To help prevent ACL injuries, learn how to land safely from a jump. Keep your knees bent and land on the ball of the foot, then rock back to the middle of the foot. Athletes should also practice cutting maneuvers using a crouched position to pivot, rather than standing upright. Instead of coming to a stop with one big step, try three little ones, keeping your knees bent.
Exercises such as leg presses and squats can help strengthen your legs. Keeping your muscles in condition and practicing skills all year round can help as well.