Anterior cruciate ligament injury
Causes and risk factors
The anterior cruciate ligament is under great strain during sports and can rupture after an injury that causes a knee ligament sprain.
The sports in which these injuries are most common are contact sports, football, skiing, basketball and volleyball.
The injury may be partial or complete, depending on the extent of the trauma.
Other knee structures such as menisci, articular cartilage, collateral ligaments and the posterior cruciate ligament can also be damaged in severe trauma.
Which are the symptoms?
When the anterior cruciate ligament is ruptured, the first symptoms are often a noise sensation in the joint, such as a clicking noise, followed immediately by significant pain inside the knee and functional impotence, i.e. the inability to use the knee.
In the first few hours after the injury, the knee is usually swollen, even significantly, and very painful.
The swelling and pain usually go away within a few weeks, during which it is important to rest, apply ice and possibly take anti-inflammatory pills. A symptom that is sometimes not immediately obvious and persists over time is the feeling of unsteadiness when changing direction and jumping, which makes it impossible to return to sports activities.
How is it diagnosed?
The diagnosis of an anterior cruciate ligament injury is mainly based on a clinical examination by an experienced orthopaedist and magnetic resonance imaging.
The clinical examination with special static and dynamic tests allows the stability of the knee to be assessed and any associated damage to be detected.
Magnetic resonance imaging makes it possible to carefully examine the structures inside the knee and detect even partial damage to the anterior cruciate ligament and any accompanying damage to other structures.
Ultrasound and CT scans of the knee are not useful examinations.
How is it treated?
In the first few minutes and days after a knee dislocation injury, treatment consists of immobilizing the knee, applying ice locally, keeping the limb elevated and using crutches for walking.
An anterior cruciate ligament injury does not usually interfere with daily activities, but it is not advisable to participate in contact sports (such as boxing and martial arts) or activities that require frequent changes of direction (such as football, basketball, volleyball).
In the first stage, it is useful to practice strengthening the thigh muscles and proprioceptive re-education of the lower limbs.
In patients with subjective instability, surgical reconstruction of the anterior cruciate ligament may be indicated to restore stability and prevent further damage to other knee structures. The decision about surgical intervention is made with the patient, after a thorough history and objective examination, assessing together with the patient the degree of instability, the age of the patient, the type of work performed and the sporting need.