I have this bulge behind my right knee, at first my doctor told me baker s cyst, but lately been have constant pain during the night, it hurts to bend, it is ok while I am walking at work, but once I get home and sit down, the pain comes. no numbness or tingling in my right leg, just pain radiating as far as my calf.
Bakers cyst are synovial cyst with joint fluid in it. It is formed due to a rent in joints capsule so that joint fluid can go in and out of this cyst. During standing due to compression over cyst by posterior knee muscles its fluid goes in to knee joint and cyst becomes empty. While seating or squatting due to coming out of knee joint fluid it is filled. That stretches its synovial lining and compresses surrounding muscles, which causes pain. Hamstring muscle stretching exercise may help you to decrease this phenomenon. If it does not work then ultrasonography guided fluid aspiration and instillation of sclerosis agent will benefit you. For this you will have to visit your Orthopedic surgeon.  Hope this helps. Hope this answers your question. If you have additional questions or follow-up questions then please do not hesitate in writing to us. I will be happy to answer your questions. Wishing you good health