Three bones meet within the knee joint: the femur (thighbone), the tibia (shinbone) and the patella (kneecap). Between the three bones lies a bursa, a fluid-filled sac that lubricates the joint. As a result of age and wear, the bursa may create extra fluid. The fluid may leak out of the wall of the bursa, forming a fluid-filled sac known as a Baker's or Popliteal cyst. The condition can be painful and often accompanies osteoarthritis, gout or a meniscal injury.Causes A popliteal cyst is caused by swelling of the bursa, or fluid filled sac, around one of the muscles that forms the hamstrings in the back of the thigh (the semimembranosus muscle). Its formation may be triggered by overuse, arthritis, injury, gout, or meniscal injury.Risk Factors Degenerative conditions of the knee, such as arthritis or meniscal injury, can put a person at risk for developing popliteal cysts. Different types of popliteal cysts affect children and the middle aged, but both are at risk of contracting them.
more
more
