Popliteal pain occurs because of the presence of cysts in the popliteal fossa, which can lead to increased pressure inside the popliteal fossa and cause painful symptoms in the popliteal fossa. Second, it is seen in patients with ligament injury in the popliteal fossa, resulting in painful symptoms in the popliteal fossa. Third, it is seen in patients with posterior meniscal horn injury, which can stimulate the ligaments and joint capsule of the popliteal fossa and cause pain in the popliteal fossa, especially when squatting and moving. Fourth, in middle-aged and elderly patients with knee degeneration and osteoarthritis, there is significant bone growth on the posterior side of the knee that can stimulate the ligaments and joint capsule in the popliteal fossa, causing pain in the popliteal fossa.