Condition Basics

What is kneecap dislocation?

The kneecap (patella) is normally positioned over the front of the knee joint at the base of the thighbone (femur). A kneecap can be dislocated, or moved out of its normal position, when:

• The inner edge of the kneecap is hit, pushing it toward the outer side of the leg. This can happen more easily if there is patellar tracking disorder (the kneecap is already slightly out of place).
• The foot is firmly planted pointing outward, and the knee is bent with the thigh turned inward. This kind of injury is common during many sports activities.

What are the symptoms?

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 it 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 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 can you care for yourself?

Home care can help you manage your symptoms. For example, don't put weight on your leg until your doctor says it's okay. Prop up your leg and use a cold pack to help reduce swelling. Take an over-the-counter pain medicine like ibuprofen or naproxen. Use a brace or bandage as directed.