What is kneecap dislocation?

Kneecap dislocation in children: Overview

A sudden twisting or a blow can cause the kneecap (patella) to move out of its normal position. This is called a dislocation. It can happen because of a sports injury—such as turning suddenly while running—or an accident.

Rest and home treatment can help your child heal and return to normal activity, usually within 3 to 6 weeks. But your child needs to be careful after healing too. Now that the kneecap has been dislocated, it can more easily go out of position again.

What are the symptoms of kneecap dislocation?

Symptoms may include severe pain, swelling, or a popping sensation, followed by a feeling that something is out of place. You may not be able to bend your knee, or it may look misshapen. You may have cool, pale skin or numbness and tingling in or below the affected knee.

How is kneecap dislocation treated?

Your doctor may recommend pain medicine, home care, and physical therapy to help you heal. The doctor may suggest using a brace (immobilizer) or elastic bandage to support your knee while it heals. In some cases, surgery may be needed.

How is kneecap dislocation diagnosed?

The doctor will ask about your symptoms and past health and do a physical exam. You may have imaging tests, such as an X-ray, ultrasound, or MRI.

How can you care for your child who has a dislocated kneecap?

  • Have your child rest the knee by not putting weight on the leg until the doctor says it is okay.
  • Put ice or a cold pack on your child's knee for 10 to 20 minutes at a time. Try to do this every 1 to 2 hours for the next 3 days (when your child is awake) or until the swelling goes down. Put a thin cloth between the ice pack and your child's skin. Do not get the brace or elastic bandage wet.
  • Prop up your child's leg on a pillow when you ice it or anytime your child sits or lies down for the next 3 days. Try to keep it above the level of your child's heart. This will help reduce swelling.
  • Be safe with medicines. Read and follow all instructions on the label.
    • If the doctor gave your child a prescription medicine for pain, give it as prescribed.
    • If your child is not taking a prescription pain medicine, ask your doctor if your child can take an over-the-counter medicine.
  • Help your child follow the doctor's instructions for using crutches, a brace (immobilizer), or an elastic bandage to support the knee while it heals.
  • If you use an elastic bandage, make sure it is snug but not so tight that your child's leg is numb, tingles, or swells below the bandage. Loosen the bandage if it is too tight.
  • Go to physical therapy if your doctor suggests it. Help your child follow the therapist's instruction for home exercises.

What is kneecap dislocation?

Kneecap dislocation occurs when a sudden twisting or a blow causes the kneecap (patella) to move out of its normal position. This can happen because of an accident or a sports injury, such as turning suddenly while running.

Kneecap dislocation: When to call

Call 911 anytime you think you may need emergency care. For example, call if:

  • You have sudden chest pain and shortness of breath, or you cough up blood.

Call your doctor now or seek immediate medical care if:

  • You have signs that your kneecap may be dislocated again, including:
    • Severe pain.
    • A misshapen knee that looks like a bone is out of position.
    • Not being able to bend or straighten the knee.
    • Not being able to walk or bear weight on the knee.
  • Your foot is cool or pale or changes color.
  • You cannot feel or move your toes or ankle.
  • You have signs of a blood clot, such as:
    • Pain in your calf, back of the knee, thigh, or groin.
    • Redness and swelling in your leg.

Watch closely for changes in your health, and be sure to contact your doctor if:

  • Your pain and swelling get worse.

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The content above contains general health information provided by Healthwise, Incorporated, and reviewed by its medical experts. This content should not replace the advice of your healthcare provider. Not all treatments or services described are offered as services by us. For recommended treatments, please consult your healthcare provider.