Anterior cruciate ligament (ACL) Damage

Anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) are located exactly in the middle of the knee. They are called “cruciate” because in their course they cross each other.

The anterior cruciate ligament attaches to the tibia from the front and runs up and back, attaching to posterior-lateral part of the top of the femur. It is hard to overestimate the function of this structure. The function that this ligament plays in the knee is extremely important.

ACL is largely responsible for the stability and proper functioning of the knee. It prevents the shin from sliding forward relative to the femur, limits the rotation of the shin, and stabilizes the knee in the frontal plane. Finally, it provides proper conditions for functioning of menisci and cartilage. Unfortunately, due to its location between two long levers (tibia and femur), the knee is exposed to high forces, hence frequent knee ligament injuries.

Football, skiing and basketball are the main sports during which knee damage is most common. Studies conducted among Italian footballers during 11 seasons have shown that 67% of football injuries concern the lower limb, of which 37% are knee injuries. 47% of knee sprains in football players are associated with damage to ACL. It is also worth mentioning that anterior cruciate ligament injury is more common in women practicing sports compared to men practicing the same disciplines.

Anterior cruciate ligament (ACL) Damage – symptoms

ACL rupture is most often associated with specific direct or torsional trauma. The athlete experiences severe pain, although he may be able to continue training. Edema of the knee rarely occurs immediately. Most often it increases within 6-24 hours. The rapid growth of the hematoma may be evidence of another accompanying pathology – e.g. intra-articular fracture. If the swelling of the knee is not large, the injury is often underestimated. An efficient mechanism of joint compensation causes that the knee gradually returns to form and the person is not aware of what threatens him.

Improperly functioning joint begins to wear out at an accelerated rate. Even normal functioning, which is associated with an average of about 1.5 million steps a year (not to mention playing sports), may result in complete destruction of the knee and in consequence may lead to knee replacement within several years. Initially there are recurrent exudates to the knee joint, knee “runaway” of the knee and muscular atrophy. Menisci and cartilage are damaged, leading to blockage of the knee and development of massive degenerative changes

Anterior cruciate ligament (ACL) Damage – treatment

A medical consultation is required immediately after knee injury. In most cases, the orthopedic surgeon is able to assess the internal damage to the knee and determine whether the anterior cruciate ligament is damaged or not by performing simple clinical tests. In case of doubt, the doctor recommends additional tests, such as ultrasound or magnetic resonance imaging. In each case, a comparative X-ray of both knees is also performed. Magnetic resonance imaging is the most accurate non-invasive knee test. In addition to visualizing the exact course of the cruciate ligaments and their internal structure, it allows the assessment of associated damage, such as meniscus damage, collateral ligament damage, patella medial straps, vitreous cartilage damage and bone contusions, as well as damage to the popliteal muscle.

In the case of confirmation of anterior cruciate ligament rupture, the most common procedure is arthroscopic reconstruction, during which a graft from the patient’s tendon is inserted in place of the damaged ligament. During the same procedure, it is also possible to repair other damage, e.g. meniscus damage.

Anterior cruciate ligament (ACL) Damage – rehabilitation

Physiotherapy after anterior cruciate ligament reconstruction surgery begins the day after surgery. Most often, for 3 to 6 weeks, the knee joint remains protected by an orthosis. The patient uses crutches while using an orthosis. Rehabilitation takes place 3 times a week with a physiotherapist, and the patient also performs exercises at home. At a certain time after the procedure, magnetic resonance imaging tests are performed to assess the healing process of the transplanted ligament and biomechanical tests to determine muscle strength and control. These tests allow for individualizing the rehabilitation process and adapting it to the individual needs of the patient and the rate of graft healing. Physiotherapy after reconstruction should last at least 12 months. After this time, if the graft signal in the magnetic resonance imaging is normal and the biomechanical tests show normal values of stabilization and muscle strength (deficits below 10% between the operated and non-operated side), the patient may plan to return to sports.

To avoid ACL damage, it is necessary to regularly strengthen the thigh muscles (especially the posterior group), stretch and perform proprioception exercises, i.e. train muscles to react properly to joint overload and to stabilize it properly, preventing ligament damage.