What is an anterior cruciate ligament (ACL) injury?

The anterior cruciate ligament is a key structure whose main function is to stabilize the knee. Therefore, patients who suffer an injury (rupture) of this ligament often have difficulty performing certain physical activities, especially those that require quick movements and changes in direction, such as soccer, basketball, martial arts, and others. Due to the joint instability caused by the ligament rupture, the patient becomes more susceptible to other injuries in the affected knee, such as meniscus and cartilage damage.

Causes

Anterior cruciate ligament (ACL) rupture usually occurs following a twisting injury to the knee. The most common mechanism happens when the patient rotates their body while the foot remains fixed on the ground. This type of movement is very common during sports activities, which is why recreational and professional athletes are the most frequently affected by this kind of injury.

Symptoms

At the moment of the injury, the individual experiences a sudden pain in the knee, and it is common for the knee to swell (increase in volume) within the first few hours after the incident.

Diagnosis

As this is a traumatic injury, the patient should always seek medical attention promptly, primarily to rule out more serious injuries that may require urgent treatment, such as fractures. Specifically for diagnosing an anterior cruciate ligament (ACL) injury, the orthopedic physical examination includes special maneuvers aimed at detecting the instability caused by the ligament rupture. To confirm the diagnosis, magnetic resonance imaging (MRI) is the most recommended test. After diagnosis, the initial priority is not the definitive treatment of the injury, but rather controlling the patient’s knee pain and swelling, allowing for the recovery of normal joint movement.

Treatment

Treatment for anterior cruciate ligament (ACL) injury may initially begin with physical therapy. However, ligament reconstruction surgery is generally the most recommended treatment, especially for younger, physically active patients and those who frequently experience a sensation of knee instability during daily or sports activities. In such patients, the risk of additional injuries is higher, which is why surgery is often chosen. The goal of surgery is to restore the normal anatomy and biomechanics of the knee and allow the patient to return to sports without the risk of new injuries.

ACL reconstruction surgery is performed via video arthroscopy and involves replacing the damaged ligament with a tendon or another ligament graft. The most commonly used tissue grafts for ACL replacement are the hamstring tendons and the patellar ligament, both harvested from the patient. The choice of graft depends on several factors, mainly related to the patient and their physical examination. Surgical techniques for ACL reconstruction have advanced significantly in recent years, and there are now various techniques available, each with its own advantages and disadvantages. Therefore, the choice of a specific technique should be discussed between the doctor and the patient, depending on the surgeon’s preference and the patient’s individual characteristics.

A crucial aspect after surgery is postoperative rehabilitation. During this phase, the patient regains normal knee movement, strength, agility, and ultimately, the confidence to return to sports. The total duration of physical therapy is no less than 6 months. There is a growing trend to extend this period, aiming for a full 9-month rehabilitation before allowing a complete return to sports.

By Einstein Editorial Board