Patellar Instability

Also known as: unstable kneecap

What is patellar instability?

Patellar instability is the scientific term for a kneecap that has become unstable. (The patella is the kneecap.) When the patella slips out of alignment, it causes pain and injury to the knee.


What causes patellar instability?

Patellar instability is often the result of a person growing a shallow or uneven femoral groove that holds the patella in place. An injury or direct blow to the kneecap can also cause patellar instability.


What are the symptoms of patellar instability?

Symptoms can include knee pain, swelling, trouble moving the knee, a knee that buckles in use, a catching sensation when moving the knee or a cracking sound coming from the knee.


What are patellar instability care options?

In many cases, a doctor can reset the patella manually with a technique called reduction. Bracing, exercises, physical therapy and surgery are other possible treatments for patellar instability.

Reviewed by: Craig Spurdle, MD

This page was last updated on: 6/14/2017 8:19:04 AM

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