Anterior Cruciate Ligament (ACL) Injury
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Overview
One of the most common knee injuries is an anterior cruciate ligament sprain or tear. Athletes who participate in high demand sports like soccer, football, and basketball are more likely to injure their anterior cruciate ligaments. 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.
Anatomy
Three bones meet to form your knee joint: your thighbone (femur), shinbone (tibia), and kneecap (patella). Your kneecap sits in front of the joint to provide some protection.
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.
Collateral Ligaments
These are found on the sides of your knee. The medial collateral ligament is on the inside and the lateral collateral ligament is on the outside. They control the sideways motion of your knee and brace it against unusual movement.
Cruciate Ligaments
These are found inside your knee joint. They cross each other to form an "X" with the anterior cruciate ligament in front and the posterior cruciate ligament in back. The cruciate ligaments control the back and forth motion of your knee. 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 providing rotational (twisting) stability to the knee.
Description
About half of all injuries to the anterior cruciate ligament occur along with damage to other structures in the knee, such as articular cartilage, meniscus, or other ligaments.
The anterior cruciate ligament can be injured in several ways:
Changing direction rapidly
Stopping suddenly
Slowing down while running
Landing from a jump incorrectly
Direct contact or collision, such as a football tackle
Symptoms
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 cushioning cartilage (meniscus) of your knee.
Knee instability
Loss of full range of motion
Tenderness along the joint line
Discomfort while walking
Treatment
Treatment for an ACL tear will vary depending upon the patient's individual needs. For example, the young athlete involved in agility sports will most likely require surgery to safely return to sports. The less active, usually older, individual may be able to return to a quieter lifestyle without surgery.
Nonsurgical Treatment
A torn ACL will not heal without surgery. But 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, Your surgeon may recommend simple, nonsurgical treatment.
Bracing: a brace may be recommended to protect your knee from instability. To further protect your knee, you may be given crutches to help with your balance.
Physiotherapy: As the swelling goes down, a careful rehabilitation program is started. Specific exercises will restore function to your knee and strengthen the leg muscles that support it.
Despite physiotherapy and activity modification, some patients’ knees will remain unstable and may require ligament reconstruction.
Surgical Treatment
ACL Reconstruction: Most ACL tears cannot be sutured (stitched) back together. To surgically repair the ACL and restore knee stability, the ligament must be reconstructed. Your surgeon 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. Hamstring tendons at the back of the thigh are a common source of grafts, and are routinely used for ACL reconstruction. Other options are the patellar tendon, which runs between the kneecap and the shinbone or the quadriceps tendon, which runs from the kneecap into the thigh, is used. Additionally, cadaver graft (allograft) and synthetic ligaments (eg LARSâ„¢ Ligaments) can be utilised.
Procedure. 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 hospital, and quicker recovery times.
Rehabilitation
Whether your treatment involves surgery or not, rehabilitation plays a vital role in getting you back to your daily activities. We have a specialised physiotherapy and rehabilitation program which has been tried and tested to get you as soon as possible.
What to expect after surgery
If surgery is decided as the best option for your ACL injury, you will stay in hospital overnight following your surgery. You can be discharged the next day with pain relief.
You will have a dressing on your surgery site and a bandage which needs to stay clean and dry for 14 days.
You can move your feet and hip straight away, but the dressing on the knee will prevent it form moving too much.
After 2 weeks you will have an appointment with to have your wound checked, any stitches will be removed.
Physiotherapy is strongly encouraged to help the knee move and to regain strength. Do not start this until you have had your appointment with Dr Stevens at 2 weeks.
There are risks with surgery. These include infection, knee pain and stiffness, graft rupture and failure to get back to high level sport. Arthritis may occur in the future as a result of the damage caused by the injury.
Frequently Asked Questions
Can an ACL tear heal without surgery?
Very minor tears can heal without requiring surgery but a full ACL tear does not usually heal by itself. If a torn ACL goes untreated, your knee may progressively wear at the joint and you may suffer from osteoarthritis.
How common is a dislocated patella or kneecap?
It is more common than you think. A dislocated kneecap isn’t usually serious, and may pop back into place by itself. In many cases, people who have a dislocated patella will not notice that it is out of place. However, it’s still a good idea to get it checked by a specialist – especially if it does not ‘pop’ back into place.
