Anterior Cruciate Ligament (ACL) reconstruction is a surgical procedure in which one of the ligaments in the knee is replaced. This surgery is used to replace a ligament which has been torn or damaged beyond repair. ACL reconstruction is especially common among athletes, as they tend to be hard on their knees, although other people may require this surgery at some point in their lives as well, depending on their level of activity.
The ACL is a critical element located inside the knee joint. It helps to stabilize the knee, and it limits the range of motion of the knee so that the risk of injury is reduced. This ligament becomes torn or damaged through violent twisting motions or repeated strain. Depending on the nature of the tear and the level of activity involved, ACL reconstruction may not always be necessary, as many tasks can be performed without this ligament. However, people who plan on any athletic activity often receive the surgery after a tear is diagnosed.
This surgery is typically performed arthroscopically, with the use of a small camera which is inserted into the joint, magnifying it and allowing the surgeon to view the joint on a screen. Once the ACL is visualized, the surgeon removes the damaged ligament to clear the way for a graft. A tendon is either harvested from somewhere else in the body in an autograft, or it is taken from a cadaver in an allograft. The surgeon drills a set of holes through the top of the shin bone and the bottom of the thigh bone, and threads the tendon through the holes, securing it so that it will eventually “take,” grafting into the joint and behaving like the missing ACL.
Grafts for ACL reconstruction can be taken from a number of places on the body, including the hamstring and the patellar tendon. The success rate for ACL reconstruction tends to be higher with autografts, as allografts carry an increased risk of complications or rejection. Typically, the graft takes within six weeks, although it can take six months or more for the patient to regain full strength.
Recovery after ACL reconstruction is focused on keeping swelling down and reducing infection in the knee in the days immediately following surgery, and then using physical therapy to build strength in the knee. Physical therapy also increases mobility, and discourages atrophying of muscles. Typically, the patient is capable of walking carefully without crutches in a week, and a physical therapist can help the patient slowly regain his or her full range of movement and prior level of physical activity.