What is an ACL Sprain and How Can You Prevent It?

A quick guide to the athlete's common knee injury

An ACL sprain, or anterior cruciate ligament sprain, is a tear or strain of a knee ligament. It’s a common injury among athletes in contact sports and it seems to happen more often in women than in men, though there is no definitive explanation as to why that is the case. The injury ranges in severity and is classified on a scale; grade 1 sprains are least severe and grade 3 sprains are most severe. 

An ACL sprain often happens when athletes change direction quickly, stop suddenly, land incorrectly from a jump or suffer a collision with another player. The injury is characterized by a “popping” sound and sudden weakness in the affected knee. Athletes might also have pain, swelling and find that they’re unable to move the knee. 

Those experiencing the above symptoms should see a doctor. After evaluation, if the doctor finds an ACL sprain, they might need surgery to repair the damage, depending on the severity of the sprain.

How Can You Prevent It?

  • Stretch your leg muscles regularly, especially after exercise
  • Strengthen leg muscles, especially quadriceps and hamstrings
  • Consider avoiding sports that require a lot of twisting and contact with other players
  • You might want to try a knee brace, but be aware that braces can also give a false sense of security