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Acl Injury

WHAT YOU NEED TO KNOW:

What is an anterior cruciate ligament (ACL) injury?

An 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. The ACL stops the tibia from sliding too far forward and keeps the knee stable.


What causes an ACL injury?

Trauma such as from a car accident or a fall may cause a tear in the ACL. An ACL injury may happen when the outer or inner side of the knee gets hit hard. This often happens in contact sports, such as football, basketball, and hockey. You may also injure your ACL. This may happen if you twist the knee while standing. You may also overextend the knee. You may cause injury if you suddenly stop or change direction while running.

What are the signs and symptoms of an ACL injury?

  • A pop, snap, or tear when your ACL is injured
  • Sudden swelling or pain in your knee
  • The knee gives way
  • A change in the way you walk, such as with stiff legs
  • Trouble putting weight on your leg or straightening the knee

How is an ACL injury diagnosed?

Healthcare providers may test the function of your ACL by moving your knee, leg, or foot in different directions. You may be asked to lean or hop using your leg with the injured knee. Tell your healthcare provider if you feel pain while you do these or other activities. Both of your knees may be checked for any abnormal movement. You may need the following tests:

  • An x-ray or MRI may be used to look for an ACL tear. You may be given contrast liquid to help the knee show up better in pictures. 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.
  • Arthroscopy is a procedure used to look inside your knee for an ACL injury. A small incision is made in your knee and a scope is inserted. The scope is a long, bendable tube with a camera and light on the end.

How is an ACL injury treated?

  • NSAIDs , such as ibuprofen, help decrease swelling, pain, and fever. This medicine is available with or without a doctor's order. NSAIDs can cause stomach bleeding or kidney problems in certain people. If you take blood thinner medicine, always ask your healthcare provider if NSAIDs are safe for you. Always read the medicine label and follow directions.
  • Acetaminophen decreases pain and fever. It is available without a doctor's order. Ask how much to take and how often to take it. Follow directions. Read the labels of all other medicines you are using to see if they also contain acetaminophen, or ask your doctor or pharmacist. Acetaminophen can cause liver damage if not taken correctly. Do not use more than 4 grams (4,000 milligrams) total of acetaminophen in one day.
  • Prescription pain medicine may be given. Ask your healthcare provider how to take this medicine safely. Some prescription pain medicines contain acetaminophen. Do not take other medicines that contain acetaminophen without talking to your healthcare provider. Too much acetaminophen may cause liver damage. Prescription pain medicine may cause constipation. Ask your healthcare provider how to prevent or treat constipation.
  • Surgery may be needed if you have an ACL tear or damage to other knee ligaments.

How can I manage my ACL injury?

  • Rest your joint so that it can heal. Return to normal activities as directed. You may not be able to play certain sports until your knee heals. Talk to your healthcare provider about sports you currently play. You may need to make a safe plan to start playing the sport again.
  • Ice helps decrease swelling and pain. Ice may also help prevent tissue damage. Use an ice pack, or put crushed ice in a plastic bag. Cover the ice pack with a towel and place it on your injured ligament for 15 to 20 minutes every hour. Use the ice for as long as directed.
  • Compression provides support and helps decrease swelling and movement so your joint can heal. Ask your healthcare provider if you should wrap an elastic bandage around your injured ligament.
  • Elevate your injured area raised above the level of your heart as often as you can. This will help decrease or limit swelling. Elevate the injured area by resting it on pillows.
  • Use support devices as directed. A knee brace may be used to limit movement and protect your child's knee. Your child may need to use crutches to help decrease pain as he or she moves around.
  • Go to physical therapy if directed. Physical therapy may be used to teach your child exercises to help improve movement and strength, and to decrease pain. The exercises can also help increase the range of motion in your child's knee.

When should I seek immediate care?

  • Your toes are cold or numb.
  • Your knee becomes more weak or unstable.
  • Your pain has increased or returned, even after you take your pain medicine.
  • Your swelling has increased or returned.
  • Your symptoms are not getting better.

When should I contact my healthcare provider?

  • You have a fever.
  • You have questions or concerns about your condition or care.

Care Agreement

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. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

© 2017 Truven Health Analytics Inc. Information is for End User's use only and may not be sold, redistributed or otherwise used for commercial purposes. All illustrations and images included in CareNotes® are the copyrighted property of A.D.A.M., Inc. or Truven Health Analytics.

The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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