What is the ACL?  
The ACL or anterior cruciate ligament is the main crossed ligament in the middle of the knee that connects the femur (thigh bone) with the tibia (shin bone) It controls the rotation of knee and prevents giving out of the knee with pivotal motions of the leg. 

Why should you have surgery to repair the Anterior Cruciate Ligament ?

You only need to have an ACL reconstruction if you are physically active in pivotal sports such as basketball, volleyball, or soccer. If you are involved in these sports only about 10% of patients who have injured their ACL can return to their sports without an ACL reconstruction. Some patients can use a brace, and modify their activities and resume sports without surgery. The best option for the young pivotal athlete is to have a reconstruction to prevent episodes of giving way due to the ACL laxity. With each of these re-injuries, there is risk of further damage to the meniscus and articular cartilage. The ACL can be reconstructed with fairly predictable results, but the long-term outcome depends on the damage to the meniscus and articular surface.  The goal of the ACL reconstruction is to provide a stable knee and prevent further damage  to the meniscus and articular cartilage.

Do I need the surgery if I'm not involved in pivoting sports?

      No. We only need the anterior cruciate ligament during pivotal motions. Sometimes the giving way sensation may be due to a torn meniscus, that may be repaired with a minor operation.
If you are an older recreational athlete you may function fine with activity modification and the use of a brace. Every surgical procedure has a risk benefit and ACL reconstruction is no exception. If you can modify your activities to avoid pivotal motions, your knee may function well without surgery.

What if I have an anterior cruciate ligament tear and I keep on pivoting sports?

      You will probably suffer giving way episodes accompanied by pain and swelling. In the long term this will cause wearing of the inside of the knee (osteoarthritis). If you want to carry on with vigorous pivoting sports, you should have an operation to reconstruct your knee.

Are you sure that the ACL is completely torn and how do you know?

            It does not matter whether the ligament is partially or completely torn. If the knee is lax, which can be measured by clinical examination or with the KT-1000 arthrometer, the ACL is not functioning to protect the knee against pivotal motions. The MRI can determine if the ligament is completely torn, but can’t differentiate the degree of laxity.

Is it possible that there is more injured than just the ACL?

            After the initial injury, there is a 50% chance of damage to the meniscus. In the acute situation the meniscus tear may be repaired. In the chronic situation, the incidence of meniscal tear is 75%, and the torn portion of the meniscus usually has to be removed.

What happens to the knee joint when the meniscus is removed?

            In the long term, the removal of all, or part of the meniscus, is associated with an increased incidence of osteoarthritis.

What's the average time to go back to sports after the surgery?

      4-6 months. Sometimes, it may take as long as 1 year to fully return to your sports.

How long is it going to take for me to go back to work?

      It depends entirely on the type of work you do,. If your work involves physical activity, it will take you 3-4 months or until your legs are strong enough; if it's sedentary work you can go back after 2-3 weeks.

When can I start driving after my surgery?

            Driving can be resumed when weight bearing is comfortable. This usually is sooner when the left knee is involved.

Is physical therapy necessary? How hard is it?

            Physical therapy is necessary from about 1- 6 weeks post op. The therapy goal is to reduce the pain and swelling, regain range of motion, and increase the strength of the muscles. Therapy may have to be modified based on the individual progress through the weeks of rehab. To view the rehab program go to http://www.carletonsportsmed.com/aclrehab.htm

Which graft is better the semitendinosus or the patellar tendon?

      The choice of a graft is immaterial. The outcome of the ACL reconstruction depends not so much on the type of graft, but on the technique of placing the graft in the correct position, the fixation of the graft and the post op rehabilitation. Because of the minimum harvest site morbidity, the commonest graft use in our sports clinic is the hamstring graft. The patellar tendon graft is used for the athlete who wants to return to sports early, for example at 3 months. The earlier return to activities is based on the faster healing of the bone to bone healing of the patellar tendon graft compared to the tendon to bone healing with the hamstring graft. The latter may take as long as 3 months to heal.

What about synthetic grafts?

      We are not routinely using synthetic materials to substitute for the ACL, because of the higher incidence of failure. These materials are indicated in special situations, such as multiple ligament injuries or some re-operations.

What about the allograft? (the graft obtained from a cadaver)

      There is some minimal risk of disease transmission. The graft takes longer to encorporate and often has tunnel enlargement as a result. The long term results have more failures with the use of the allograft.

How long do I have to use the special knee brace?

      After the surgery you'll have to use a Zimmer extension splint, or a functional brace for 4-6 weeks (to protect the graft until it heals to the bone). You can go back to sports 4-6 months after surgery, but with the brace on. You can get rid of the brace a year after the procedure.

Do I need another surgery to remove the screws?

      No, the screws that we use are made of a special sugar type compound that will dissolve in a couple of years after the surgery.

Is the surgery a day care procedure?

      Yes, you'll spend just a few hours in the hospital day care recovery room after the surgery.

Does the giving way cause pain after the acute episode?

      Yes. It also can cause more damage to the articular surface and the meniscus. (leading to late osteoarthritis)

Does the harvest of the graft cause a problem with the knee later on?

      Yes. There is some weakness of the hamstrings after removal of the semi-tendinosus and the gracilus tendons. There is usually no weakness after patellar tendon harvest, but pain around the knee cap is common post-operatively.

Will my knee wear out early if I don't have my ACL fixed?

            More damage to the articular surface, or ‘wearing out’, will occur if the knee continues to give way. Giving way should be prevented by activity modification, bracing or surgical reconstruction. Don Shelbourne MD has shown that if the ACL tear is isolated, and there is no meniscal or cartilage damage at the time of the original surgery, the x-ray of the knee will be normal in 97% of the cases. This means that athletes who have a reconstruction and continue to be active can have a normal knee after 10 years.

What are the potential complications of ACL surgery?

            The complications that may occur after ACL reconstruction are those that are related to any surgical procedure such as infection, and deep venous phlebitis (blood clot in the calf). The complications specifically related to the operation are loss of range of motion, anterior knee pain, persistent pain and swelling, and residual ligament laxity due to graft failure. An injury to the nerves or blood vessels after this type of surgery is extremely uncommon.