Anterior cruciate ligament (ACL) injury is a particularly common knee injury that affects 100,000 to 200,000 people each year in the United States. It is the same injury that Tiger Woods struggled with when he won the US Open Golf Championship in 2008 and subsequently, had surgery on.
What is it? The anterior cruciate ligament (ACL) helps to stabilize the knee joint by preventing excessive movement of the shin bone (tibia) relative to the thigh bone (femur). Specifically, it prevents excessive back to front, side to side and rotational movement in the joint.
If the ACL is either partially or fully torn, the knee becomes unstable, which can ultimately lead to cartilage damage or arthritic changes.
What are the causes/predisposing factors? The most common causes of an ACL injury are from cutting (quick changes in direction or pivoting) and sudden deceleration such as landing from a jump. Other causes can include contact type injuries as well.[ad#Adsense]
In Tiger Woods’ case, he had an under developed ACL that had been further compromised by the presence of cysts in the knee that had to be surgically removed. This left him with a fragile ACL that let go on a simple training run.
What are the symptoms? In most cases, the person will hear a ‘pop’ as the ACL ruptures. This is followed immediately by pain and swelling.
Walking with a limp and a feeling that the leg will “give way” on weight bearing is a typical presentation.
What can be done to prevent or treat this condition? Prevention is geared towards those that already have a pre-existing ACL injury. This involves limiting activities such as pivoting, cutting, aggressive stops and landing with the foot fixed in a stationary position. Note that most normal activities can be performed with little problem on a damaged ACL; it is only with more aggressive movements that the ACL becomes an issue.
There are two options for treatment: surgical or conservative.
Surgical care should be reserved for those who wish to resume aggressive activities and for those who have ongoing instability. Surgery consists of replacing the damaged ACL with either a portion of the patellar tendon or hamstrings tendon.
Conservative care involves primarily strengthening the hamstring muscle to help stabilize the knee, and then later, strengthening the other muscles around the knee. As well a regimen to restore knee mobility, full range of motion is included in the overall care.
The overall goals of both treatment plans are to restore stability to the knee and to prevent future cartilage damage and osteoarthritis.