What causes an ACL injury?

Most anterior cruciate ligament (ACL) injuries are the result of a specific trauma and are associated with a pivoting or twisting motion. Your knee joint consists of three bones: the femur (thighbone), tibia (shinbone) and patella (knee cap). Four bands of tissue called ligaments hold the bones together and keep them stable. The two collateral ligaments control sideways movement within the knee. The anterior (front) cruciate ligament and posterior (rear) cruciate ligament cross each other to make an X and control forward and backward motion.

ACL injuries can occur from:

  • changing direction rapidly
  • stopping suddenly
  • slowing down while running
  • landing from a jump incorrectly
  • making direct contact or colliding, such as a football tackle

Trinity Health is a Catholic health care organization that acts in accordance with the Catholic tradition and does not condone or support all practices covered in this site. In case of emergency call 911. This site is educational and not a substitute for professional medical advice, always seek the advice of a qualified health care provider.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.