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Anterior Cruciate Ligament Injury


An anterior cruciate ligament (ACL) injury is a partial or complete tear of the ACL. The ACL is a ligament in your knee that connects the tibia (shin bone) to the femur (thigh bone). Ligaments are strong tissues that connect bones together. The ACL stops the tibia from sliding too far forward and keeps the knee stable.


You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your caregivers to decide what care you want to receive. You always have the right to refuse treatment.


Repeated injuries to your ACL can cause long-term damage. This can lead to a weak, unstable knee, even during normal activities. You may feel your knee give way more often. When the ACL is injured, other ligaments of the knee may also be affected. One or more of the menisci (cartilage shock absorbers between knee bones) may also be damaged. Injury to the ACL may cause the ligament to pull off a part of the shin bone. Even with treatment, the knee may not be the same as it was before the injury.


Informed consent

is a legal document that explains the tests, treatments, or procedures that you may need. Informed consent means you understand what will be done and can make decisions about what you want. You give your permission when you sign the consent form. You can have someone sign this form for you if you are not able to sign it. You have the right to understand your medical care in words you know. Before you sign the consent form, understand the risks and benefits of what will be done. Make sure all your questions are answered.


You may be given medicines to reduce pain, swelling, or fever.

Physical therapy:

A physical therapist teaches you exercises to help improve movement and strength, and to decrease pain.


  • Arthroscopy is a procedure used to look inside your knee to check your ACL injury. Healthcare providers make a small incision in your knee and insert a scope through it. The scope is a long tube with a camera and light on the end.
  • An x-ray or MRI may be used to look for ACL tears or other injuries. You may be given contrast liquid to help the pictures show up better. Tell a healthcare provider if you have ever had an allergic reaction to contrast liquid. Do not enter the MRI room with anything metal. Metal can cause serious injury. Tell the healthcare provider if you have any metal in or on your body.


You may need surgery to repair an ACL tear or to reconstruct the ligament.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Learn more about Anterior Cruciate Ligament Injury (Inpatient Care)

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Symptoms and treatments

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