Knee bursitis

Knee bursitis is inflammation of a bursa located near your knee joint. A bursa is a small fluid-filled, pad-like sac that reduces friction and cushions pressure points between your bones and the tendons and muscles near your joints.

Each of your knees has 11 bursae. While any of these bursae can become inflamed, knee bursitis most commonly occurs over the kneecap or on the inner side of your knee below the joint.

Knee bursitis causes pain and can limit your mobility. Treatment for knee bursitis often includes a combination of self-care practices and doctor-administered treatments to alleviate pain and inflammation.

Symptoms Causes Risk factors Prevention

Knee bursitis signs and symptoms may vary, depending on which bursa is affected and what precisely is causing the inflammation.

In general, the affected portion of your knee may feel warm, tender and swollen when you put pressure on it. You may also feel pain when you move or even at rest.

A sharp blow to the knee can cause symptoms to appear rapidly. But most cases of knee bursitis result from repetitive injuries — sustained in jobs that require a lot of kneeling — so symptoms usually begin gradually and may worsen over time.

When to see a doctor

The bursa that lies over your kneecap can sometimes become infected. Call your doctor if you have a fever in addition to pain and swelling in your knee.

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