An ACL tear is mostly common during sports that involve a sudden change in direction or stop. Downhill skiing, soccer, football and basketball are some of these sports. Gymnasts may also accidentally twist their knees during a performance.
The manner in which you twist your knee plus your speed makes it highly probable that you’ll tear or stretch your ligament. Research shows that women are more likely to suffer from it than men.
What are some of the symptoms of an ACL injury?
Knee Pain and Swelling
Also referred to as “water on the knee”, knee swelling happens when vessels that supply the ACL with blood fill the joint space with blood. Swelling is huge and noticeable and happens within minutes of the sprain.
The swelling causes pain, which varies in intensity depending on the amount of damage done around and in the knee joint.
The pain and swelling make it difficult for doctors to determine if the ligament is loose and to test the stability of the knee. They, therefore, use an MRI, or magnetic resonance imaging, scan.
Hearing a Loud “Pop”
The “pop” sound is not only audible to a player, but bystanders from the sideline of a soccer or football game as well.
It is a terrifying sound that is caused by the tearing of the ACL. A less-common alternative to the “pop” is a feeling of rapid shift in the joint.
An MRI scan may be a common way to check for cartilage or ligament damage and meniscus tears, but it is less commonly used in many cases. Many doctors rely on physical examination to diagnose an ACL sprain.
They will also perform an examination on your knee to check the degree of the injury and your range of motion. They turn to MRI if there is no damage of your bones.
Instability of the Knee
Knee stability is maintained by the shape of the menisci and condyles combined with the ACL, as well as other passive supporting structures, which are the lateral collateral ligament (LCL), the medial collateral ligament (MCL), and the posterior cruciate ligament (PCL).
Instability, or giving out, happens due to indirect or direct trauma. Some of the common causes of giving out are pivoting, jumping, twisting or cutting movements in a majority of sports.
Abnormal Physical Tests
An easy way for doctors to evaluate the ligaments of your knee is through particular tests. Tests that they use to tell if your ACL has torn include:
- Drawer test, which is carried out with the knee held with a 90-degree bend. The tibia is shifted back to test for an intact PCL and forward for a normally-functioning ACL.
- Lachman test, which is done to test for unusual forward movement of the tibia.
- Pivot shift maneuver, which is performed mostly in an operating room on a patient under anesthesia. It helps in identifying an irregular movement of the knee joint when an ACL sprain is present.