The anterior cruciate ligament is one of the major stabilising ligaments in the knee. It is a strong rope like structure located in the centre of the knee running from the femur to the tibia. When this ligament tears unfortunately it doesn’t heal and often leads to the feeling of instability in the knee.
The Anterior Cruciate Ligament (ACL) is the major stabilising ligament of the knee. The ACL is located in the centre of the knee joint and runs from the femur (thigh bone) to the tibia (shin bone), through the centre of the knee. The ACL prevent the femur from sliding backwards on the tibia (or the tibia sliding forwards on the femur). Together with the posterior cruciate ligament (PCL), ACL stabilises the knee in a rotational fashion. Thus if one of these ligaments is significantly damaged, the knee will be unstable when planting the foot of the injured extremity and pivoting, cause the knee to buckle and give way.
A torn ACL makes the knee vulnerable to re-injury because it is not stable in certain activities.
Successful ACL reconstruction surgery tightens your knee and restores its stability. It also helps you avoid further injury and get back to playing sports.
The hamstring muscles are the group of muscles on the back of your thigh. When the hamstring tendons are used in ACL surgery, two of the tendons of these muscles are removed, and “bundled” together to create a new ACL. Over the years, methods of fixing these grafts into place have improved.
The most common problem following ACL surgery using the patellar tendon is pain over the front of the knee. Some of this pain is known to be due to the graft and bone that is removed. This is not a problem when using the hamstring tendon. The incision is also smaller, and the pain both in the immediate post-operative period, and down the road, is thought to be less.
The major cause of injury to the ACL is sports related. This injury occurs when the knee is forcefully twisted of hyper extended. Usually the tearing of the ACL occurs with a sudden directional change with the foot fixed on the groups of when a deceleration force crosses the knee.
The ACL can be injured in several ways:
- Changing direction rapidly
- Slowing down when running
- Direct contact – such as football tackle
Many patients recall hearing a loud pop when the ligament tears and feel the knee buckle.
There is a rapid onset of the swelling within the first two hours, and patients usually complain of a buckling sensation in the knee during twisting movements.
The symptoms following the tear of the ACL are variable. Usually there is swelling of the knee within a short time following the injury due to bleeding in the knee joint from torn blood vessel in the ligament.