A Baker's cyst, also known as a popliteal cyst, is a pocket of joint fluid that forms a lump behind the knee. Often a Baker's cyst is painless, but occasionally this pocket of fluid can tear open and drain into the tissues of the lower leg, causing pain and swelling.
            Symptoms include:
            
              - Swelling behind the knee that may increase when a person stands.
 
              - Discomfort behind the knee and into the upper calf, especially when the knee is completely bent or straight.
 
            
           
         
        
          
            
              Current as of: July 31, 2024