Search Encyclopedia:    
List of Topics Print This Page
 

Anterior cruciate ligament (ACL) injury


Alternative Names:

Cruciate ligament injury - anterior; ACL injury; Knee injury - anterior cruciate ligament (ACL)

Symptoms:

Early symptoms:

  • A "popping" sound at the time of injury
  • Knee swelling within 6 hours of injury
  • Pain, especially when you try to put weight on the injured leg

Those who have only a mild injury may notice that the knee feels unstable or seems to "give way" when using it.

First Aid:

See your health care provider if you think you have an ACL injury. Do not play sports or other activities until you have seen a doctor and been treated.

Your doctor may send you for an MRI of the knee. This can confirm the diagnosis. It may also show other knee injuries.

First aid for an ACL injury may include:

  • Raising your leg above the level of the heart
  • Putting ice on the knee
  • Pain relievers such as nonsteroidal anti-inflammatory drugs (such as ibuprofen)

You may need:

  • Crutches to walk until the swelling and pain get better
  • Physical therapy to help improve joint motion and leg strength
  • Surgery to rebuild the ACL

Some people can live and function normally with a torn ACL. However, most people complain that their knee is unstable and may "give out" with physical activity. Unrepaired ACL tears can lead to further knee damage.

Do Not:
  • Do NOT move your knee if you have had a serious injury.
  • Use a splint to keep the knee straight until you see a doctor.
  • Do NOT return to play or other activities until you have been treated.
When to Contact a Medical Professional:

Anyone with a serious knee injury should seek medical attention for x-rays and evaluation.

If the foot is cool and blue after a knee injury, the knee joint may be dislocated, and blood vessels to the foot may be injured. This is a medical emergency that requires immediate professional help.

Prevention:

Use proper techniques when playing sports or exercising. Some college sports programs teach athletes how to reduce stress placed on the ACL.

The use of knee braces during aggressive athletic activity (such as football) is controversial, and has not been shown to reduce the number of knee injuries.

References:

Cimino F, Volk BS, Setter D. Anterior cruciate ligament injury: diagnosis, management, and prevention. Am Fam Physician. 2010;82:917-922.

Griffin LY, Armstrong A, DeMaio M. The female athlete. In: DeLee JC, Drez D Jr, Miller MD, eds. DeLee and Drez's Orthopaedic Sports Medicine. 3rd ed. Philadelphia, PA: Elsevier Saunders; 2009:chap 10.

Honkamp NJ, Shen W, Okeke N, Ferretti M, Fu FH. Anterior cruciate ligament injuries: 1. Anterior cruciate ligament injuries in the adult. In: DeLee JC, Drez D Jr, Miller MD, eds. DeLee and Drez's Orthopaedic Sports Medicine. 3rd ed. Philadelphia, PA: Elsevier Saunders; 2009:chap 23, section D.


Review Date: 8/14/2011
Reviewed By: Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine, Seattle, WA; C. Benjamin Ma, MD, Assistant Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 2002 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

   View History
  Anterior cruciate ligament (ACL) injury

Related Links
Request an Appointment Online or call
1-800-789-PENN (7366)
ACL reconstruction
Knee arthroscopy
   
   

 

About UPHS   Contact Us   Site Map   Privacy Statement   Legal Disclaimer   Terms of Use

The University of Pennsylvania Health System, Philadelphia, PA 1-800-789-PENN © 2014, The Trustees of the University of Pennsylvania