Popliteal effusion can be caused by popliteal injury, osteoarthritis of the knee, bursitis, etc., which can be treated with general therapy, medication and surgery. 1. Popliteal fossa injury: ligament and joint capsule injury in popliteal fossa can cause popliteal fossa effusion, which needs to be rested with localized braking and elevation to avoid aggravating the injury with continued activities, and if the injury is serious, surgery should be carried out to repair the injury, which can help to alleviate popliteal fossa effusion. 2. Osteoarthritis of the knee joint: when osteoarthritis of the knee joint occurs, degeneration of the knee joint and local osteophytes can stimulate the joint capsule and ligaments in the popliteal fossa, which can lead to the production of joint effusion. Should reduce the knee joint activities, can be applied under the guidance of the doctor to improve the circulation of drugs such as Mai Zhi Ling, the feasibility of joint cavity puncture extraction treatment, and can be injected into the sodium hyaluronate nutrition lubrication of the articular cartilage, the serious need to carry out surgical treatment such as knee joint replacement. 3. Synovitis: Synovitis in the popliteal fossa can lead to fluid accumulation in the popliteal fossa. Appropriate rest is needed to reduce joint activities and synovial membrane stimulation and proliferation, feasible hot compresses and physical therapy to improve local circulation, promote the repair of synovial inflammation, oral anti-inflammatory and analgesic medications such as Celecoxib can reduce synovial swelling, promote synovial membrane repair, and reduce the popliteal effusion. When popliteal effusion should be timely medical consultation, under the guidance of specialists to actively carry out appropriate treatment, can help early relief of discomfort symptoms.