Anterior Cruciate Ligament Injury

What is the Anterior Cruciate Ligament? What is its function in the knee joint?

The anterior cruciate ligament (ACL) is an approximately 3-3.5 cm long ligament located in the central part of the knee joint. Its primary function is to prevent the knee from sliding forward or rotating.

How does the Anterior Cruciate Ligament get injured?

The anterior cruciate ligament is typically injured following a rotational movement of the knee joint while the foot is fixed (indirect trauma). During the injury, a popping sound may be heard from the knee joint. In the acute phase following the injury, swelling and pain in the knee develop due to bleeding. The athlete is unable to continue playing.

In patients who do not receive treatment during the acute phase, knee swelling and pain typically subside within 2-3 weeks. However, in untreated patients, during the chronic phase, particularly during sports activities requiring sudden turns such as football or basketball, recurrent feelings of the knee giving way, weakness, or complaints due to repeated rotations may occur. This condition is referred to as anterior cruciate ligament insufficiency. In these clinical situations, new meniscal tears and cartilage injuries, which were not present in the acute phase, may develop.

How is an Anterior Cruciate Ligament injury treated?

The treatment decision for patients is based on factors such as the patient’s age, activity level, the presence of additional injuries, and whether the tear is partial or complete.

In active, young patients who wish to continue their sports activities after the injury, surgical treatment should be applied. During the surgery, concurrent treatment of meniscal tears and cartilage injuries is also performed.

The anterior cruciate ligament most commonly tears in its midsection. Due to impaired blood supply to the ligament and the joint fluid preventing primary healing, spontaneous healing of the torn ligament or repairing it by suturing is not possible.

Several different techniques are used for anterior cruciate ligament surgery. In the most commonly applied technique, tendons harvested from various parts of the body are prepared using specific techniques, passed through bone tunnels created using an arthroscopic (closed) method, and fixed to the bone. As a result, a new anterior cruciate ligament is created to provide similar functionality.

Figure: Arthroscopic anterior cruciate ligament reconstruction surgery