Knee chondromalacia, or else known chondromalacia patellae, is a common painful medical condition which affects primarily the patellar cartilage, secondly the femoral cartilage and the tibial cartilage only in cases where the two meniscuses are worn or removed.
In 1877 Baker noticed the existence of synovial fluid cysts in the popliteal cavity, which received his name. The popliteal cyst occurs on the posterior internal surface of the knee between the internal head of the gastrocnemius and the tendon of the semimembranosus muscle (insertion). In essence, it is a synovial fluid that escapes from the pouch and cannot return to the joint.