Symptoms

In some cases, a Baker's cyst causes no pain, and you may not notice it. If you do have signs and symptoms, they might include:

• Swelling behind your knee, and sometimes in your leg
• Knee pain
• Stiffness and inability to fully flex the knee

Your symptoms may be worse after you've been active or if you've been standing for a long time.

When to see a doctor

If you have pain and swelling behind your knee, see your doctor. Though unlikely, a bulge behind your knee may be a sign of a condition more serious than a fluid-filled cyst.