When you twist your knee or fall on it, you can tear a stabilizing ligament that connects your thighbone to the shinbone. An anterior cruciate ligament (ACL) unravels like a braided rope when it’s torn and does not heal on its own. Fortunately, reconstruction surgery can help many people recover their full function after an ACL tear.
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. People often tear the ACL by changing direction rapidly, slowing down from running or landing from a jump. Young people (age 15-25) who participate in football and rugby and other sports that require pivoting are especially vulnerable. You might hear a popping noise when your ACL tears. Your knee gives out and soon begins to hurt and swell.
First treatment includes rest, ice compression and elevation (RICE) plus a brace to immobilize the knee, crutches and pain relievers. An early orthopaedic evaluation is advisable.
Evaluation
A physical examination of the knee will be required and X-rays to determine if there is any associated bony injury. Usually an MRI scan will be indicated as this shows up injury to ligaments and menisci (cartilages) and allows a more accurate assessment of the injury. Quite frequently it may be necessary to have reconstructive surgery, particularly if you participate in sporting activities that involve a lot of twisting and turning. The damaged ACL is replaced 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. This is then threaded through the inside of your knee joint and the ends are secured 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 nonsurgically with a program of muscle strengthening.
Outcome
Successful ACL reconstruction surgery tightens your knee and restores its stability. It also helps you avoid further injury and gets you back to playing sports. This type of surgery is successful about 85-90 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 six to nine months after the surgery.
content written by Johan Witt Hip othopaedic and trauma surgeon
