An anterior cruciate ligament (ACL) injury is a tear in the ACL ligament. The ACL is located in the middle of the knee joint. It connects the lower leg bone to the thigh bone. It stabilizes the knee and prevents the lower leg bone from sliding too far forward at the knee.

Anterior Cruciate Ligament Injury
ACL injury
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ACL injury occurs when your knee gets twisted or during a hard landing from a jump. It can also happen with:

  • Sudden stops or changes in direction
  • Sidestepping or pivoting
  • Direct contact