What is a Cruciate Ligament Injury?
Inside the knee joint, there are two strong bands that cross each other: the anterior and the posterior cruciate ligament. These function as the backbone of the knee's stability and prevent the lower leg from sliding abnormally in relation to the thigh bone. A cruciate ligament injury means that one of these bands has been stretched or torn completely. Cruciate ligament injuries can affect anyone, but are most common in:
- Anterior Cruciate Ligament (ACL): By far the most common injury, often occurring during twisting movements.
- Posterior Cruciate Ligament (PCL): Less common, often caused by powerful force to the lower leg.
Common Symptoms of a Cruciate Ligament Injury
How a cruciate ligament injury feels varies depending on whether it is a total rupture or a minor partial tear. Here are common symptoms:
Symptoms of an Acute Injury
- A loud pop or a "popping" sound inside the knee at the moment of injury
- Immediate and intense pain that makes it difficult to put weight on the leg
- Rapid swelling of the knee (often within just a few hours)
- A feeling that the knee "gives way" or feels unstable
Symptoms After the Acute Phase
- Recurring instability during changes of direction or on uneven surfaces
- Difficulty trusting the knee in everyday life
- Diffuse aching and stiffness after physical exertion
- Reduced muscle mass in the thigh due to inactivity
Why Do Cruciate Ligament Injuries Occur?
A cruciate ligament injury usually occurs during heavy strain where the knee is forced in an unnatural direction. Causes can include:
- Powerful twisting: The foot gets stuck in the surface while the body rotates.
- Sudden stops and changes of direction: Common in sports like football, floorball, and handball.
- Landings: An incorrect landing after a jump where the knee collapses inward (valgus stress).
- Direct trauma: A collision or tackle against the knee.
- Anatomy and gender: Statistically, women have a higher risk due to anatomical and hormonal factors.
When Should You Seek Care?
Contact a healthcare provider if:
- Your knee swells significantly after a trauma or fall
- You cannot put weight on the leg normally after an injury
- You experience the knee being unstable and "giving way"
- You have persistent pain that does not improve with rest
How to Find Out if You Have a Cruciate Ligament Injury
Do you have symptoms that you suspect are due to a cruciate ligament injury? A first step is to book an appointment with a doctor or physiotherapist. They perform manual tests (such as stability tests) to assess whether the cruciate ligament is intact.
If the clinical examination suggests an injury, or if the knee is too swollen to be examined properly, an MRI scan of the knee is the most reliable method. With an MRI, one can clearly see if the cruciate ligament is torn or damaged, as well as if there are other simultaneous injuries to the menisci or joint cartilage. This is crucial for planning the right treatment, whether it involves surgery or specific rehabilitation.