ANATOMY - Anterior Crucitate Ligament (ACL)
The anterior cruciate ligament (ACL) is a ligament that connects the tibia to the femur. It serves to prevent the tibia (leg) from moving forward relative to the femur (thigh). The ACL is in the center of the knee. It crosses the PCL, hence the name, cruciate.
How does someone injure the ACL?
This ligament is frequently injured in contact sports (e.g., football) and pivoting sports (such as soccer and skiing), however there are many scenarios for injury to this ligament. Usually the patient complains of a sudden injury to the knee and the inability to walk right after the accident. Often, there is a significant amount of swelling that occurs relatively soon after the injury. In contact sports (e.g., football) the injury typically occurs when another player impacts the side of the knee. Non-contact ACL injuries are more common in women, such as a female soccer player who suddenly changes direction and feels a pop in her knee.
What are the symptoms of an ACL injury?
Initially, the symptoms are pain and fairly immediate swelling. Often patients will complain of hearing a loud "pop", which is the sound of the actual ligament tearing.
After the pain and swelling resolve, patients complain of episodes of instability, or giving-way. The knee feels loose. Some people liken this to walking on rollerskates. For some people, this looseness is predictable; other people live in fear of their knee giving out because they are unable to predict the motions that cause the instability.
What happens after the ACL injury?
It depends on the severity of the injury and whether there are any other associated injuries, such as a medial collateral ligament tear or a meniscal tear. Often the swelling resolves after a couple of weeks. Some patients will be able to function without any problems after they get over the initial injury, especially if they had only a partial tear. The majority, however, will notice "instability"; the feeling that their lower leg is shifting forward on their thigh bone. For some, this will be a minor nuisance; for others, it will be a significant disability.
The first step is to get your pain under control.
This should be done regardless of whether you plan to have surgery or not. Because of the swelling (caused by blood in the knee), the knee will be difficult to extend (make straight) for several days. Cryotherapy is an important aide in relieving pain and decreasing the swelling. You can use an icebag if you wish, but that can be inconvenient and messy. If you have significant swelling or pain, we think you will find our Breg PolarCare Cub, our DonJoy IceMan or our DuraSoft Knee products of help in maintaining joint comfort.
Second, get your motion back!
It is imperative to get the motion in your knee back as quickly as possible (after resting for a few days) to prevent a permanent loss of motion ("contracture"). This is achieved with various exercises. If you have access to a gym or physical therapy, great. Other people may benefit from our Deluxe Knee Therapy Kit. This will help you to do exercises in the comfort of your home and not have to worry about getting out of the house to get to physical therapy or the gym. In addition, your doctor will often recommend a brace, such as the DonJoy IROM brace, to help you regain motion while protecting the knee from further injury.
Important note: Even if you plan to have the ACL reconstructed, most orthopedic surgeons will not reconstruct your knee until you have regained your motion! The reason is simple; if you start off with a stiff knee before surgery, you will end up with a stiff knee after surgery.
Once you regain your motion, the decision needs to made whether you will need surgery.
How do you and your doctor decide if you need surgery?
This is a very complicated question and generally can only be answered by discussion with your orthopedic surgeon. There are a few guidelines, however. Typically, the decision to reconstruct the ACL is based on the following:
- Patient's age and activity level.
- Associated injuries, such as a meniscal tear, medial collateral ligament injury, or significant cartilage injury.
- Response to rehabilitation.
- Amount of instability and magnitude of the patient's symptoms.
Generally speaking, a young high school football player who injures his ACL and wants to continue to compete at the same level or higher (e.g., college play) will require a reconstruction. Another player may decide that he doesn't want to play football ever again and is happy surfing the internet and swimming; this person may not require an ACL reconstruction. A 32-year-old skiier who has injured her ACL and medial meniscus, and wants to continue to ski recreationally, should probably have her ligament reconstructed. As you can see, the permutations are endless; the decision needs to be made on a patient-by-patient basis with a surgeon who knows you and your lifestyle demands. Most sports medicine orthopedic surgeons do not place an "upper age limit" on whether to reconstruct the ACL.
If you and your doctor have decided on surgery to reconstruct the ACL, then you will want to learn more about ACL reconstruction surgery.
If surgery is not necessary, then strengthening excercises, particularly of the hamstrings are prescribed. Non-operative exercise therapy for ACL tears includes:
- Maintaining range of motion.
- Regaining stability by improving your muscle strength. By strengthening the muscles you can compensate for the absence of the ligament.
- Knee bracing to help you regain stability of your knee, especially for sports. For significantly unstable knees; or for return to competitive sports where you can't afford to be slowed down, no brace can surpass the DonJoy eXtreme Knee Brace in stability and comfort. Ossur/Innovation Sports also offers the Ossur CTi OTS Pro Sport Knee Brace, which allows you to obtain the technologies found in the CTi custom knee brace at a fraction of the cost. The DonJoy Legend Knee Brace is the former top-of-the-line brace that also provides excellent stability and light weight, at a lower cost. We also offer the DonJoy Playmaker Knee Brace as a solution for moderate instability, even for those people who want to return to contact sports. Our Drytex Hinged Knee Brace is great for people with mild instability who want some extra support, particularly in side-to-side motions.
