Bones are connected to other bones by ligaments. There are four primary ligaments in your knee. They act like strong ropes to hold the bones together and keep your knee stable.
The cruciate ligaments are found inside your knee joint. They cross each other to form an “X” with the anterior cruciate ligament (ACL) in front and the posterior cruciate ligament (PCL) in back. The cruciate ligaments control the back and forth motion of your knee.
When the ACL gets disrupted, your knee will feel unstable and it becomes more difficult to run and perform sudden changes in direction and acceleration
Anterior Cruciate Ligament (ACL) Ruptures
The anterior cruciate ligament runs diagonally in the middle of the knee. It prevents the tibia from sliding out in front of the femur, as well as provides rotational stability to the knee. If you have injured your anterior cruciate ligament, you may require surgery to regain full function of your knee. This will depend on several factors, such as the severity of your injury and your activity level. The anterior cruciate ligament can be injured in several ways:
Changing direction rapidly
Slowing down while running
Landing from a jump incorrectly
Direct contact or collision
When you injure your anterior cruciate ligament, you might hear a “popping” noise and you may feel your knee give out from under you. Other typical symptoms include: Pain with swelling. Within 24 hours, your knee will swell. If ignored, the swelling and pain may resolve on its own. However, if you attempt to return to sports, your knee will probably be unstable, and you risk causing further damage to the cartilage of your knee.
Your orthopedic doctor will be able to diagnose if you had a severe injury to the ACL by conducting a physical exam and obtaining imaging studies such as a MRI
Nonsurgical treatment may be effective for patients who are elderly or have a very low activity level. If the overall stability of the knee is intact, the orthopedic doctor may recommend simple, nonsurgical options.
If your knee remains painful and unstable, surgical reconstruction may be indicated. Most ACL tears cannot be sutured (stitched) back together. To surgically repair the ACL and restore knee stability, the ligament must be reconstructed. Your doctor will replace your torn ligament with a tissue graft. This graft acts as a scaffolding for a new ligament to grow on.
Grafts can be obtained from several sources. Often, they are taken from the patellar tendon, which runs between the kneecap and the shinbone. Hamstring tendons at the back of the thigh are a common source of grafts as well. Sometimes a quadriceps tendon, which runs from the kneecap into the thigh, is used. Finally, cadaver graft (allograft) can be used.
There are advantages and disadvantages to all graft sources. You should discuss graft choices with the orthopedic surgeon to help determine which is best for you.
Surgery to rebuild an anterior cruciate ligament is done with an arthroscope using small incisions. Arthroscopic surgery is less invasive. The benefits of less invasive techniques include less pain from surgery, less time spent in the hospital, and quicker recovery times. Because the healing and regrowth takes time, it may be six months or more before an athlete can return to sports after surgery.