Q: What is the 'Anterior Cruciate Ligament' ?
A: The Anterior Cruciate Ligament (ACL) is a strip of strong fibrey tissue, which is located deep inside the knee joint. It runs form the Back-Outer femur (thigh bone) to the anterior tibia (shin bone), deep within the knee. No part of it can be seen or felt form the outside.
The function on the ACL is to provide stability for the knee. In particular, the ACL is responsible for preventing the tibia form sliding forward and leaving the femur behind (OUCH!! it even hurts to describe it). In addition, the ACL helps to prevent rotation of the tibia.
Q: What are the Symptoms of ACL injury ?
A: When the ACL is injured, the knee often feels like it 'buckles', 'gives way', or 'pops'. Swelling often occurs very quickly after the injury, often making the knee difficult to to move.
When the knee is examined by a physician, the doctor will look for signs of swelling and instability of the knee.
Q: What are the possible side effects of having surgical repair of an ACL rupture ?
A: Repair of the ACL by surgery, either via 'open' or 'arthroscopic' techniques is relatively safe. Approximately 1-2% of people will have some degree of disatisfaction, either severe or minor. Of this 1-2%, these are the most likely causes for disatisfaction:
Arthrofibrosis (development of scar tissue in the knee, which may limit movemnt
Deep Venous Thrombosis (development of blood-clots in the leg veins)
Poor Knee Motion
Infection of the Joint
Injury to the Patella (kneecap) [usually a small piece of bone and tendon are removed for the kneecap to form the new ACL]
The most important decision in making the choice for or against surgery is an honest appraisal of your current symptoms, and discussion with your surgeon as to the risks and benefits of the procedure.
Although multiple types of repair are possible, the most common repairs use either the patellar tendon or a portion of the hamstring tendon (Semitendinosus and gracilis). A recent meta-analysis by Yunes et al indicates that Patellar tendon repairs are generally more successful, allowing more chance of returning to pre-injury activity levels and less laxity.
Q: Is it common for an injury of the ACL to lead to damage of the meniscus of the knee ?
A: When the ligaments of the knee rupture, the knee becomes much less stable than it should be. This allows the surfaces of the knee to collide with one another, often damaging the internal structures. In particular, because the menisci fit in between the two main bones of the knee, they are frequently damaged.
The most frequent association is meniscus injury due to an ACL rupture. Aproximately 80% of ACL tears will lead to a meniscus injury.