Pain in the posterior fossa of the knee can be caused by trauma, rheumatoid arthritis, popliteal cysts, etc. It can be treated by flurbiprofen gel paste, indomethacin babu cream and so on. 1. Trauma: If the pain in the posterior knee socket is caused by muscle strain or cold, you can choose flurbiprofen gel paste. You can choose anti-inflammatory and analgesic drugs such as flurbiprofen gel paste. 2. Rheumatoid arthritis: If rheumatoid arthritis causes pain in the back of the knee. You can choose the local application of drugs, such as diclofenac diethylamine latex, etc., or the external paste of the ointment, such as indomethacin babu cream. 3. Popliteal cysts: If popliteal cysts cause pain in the posterior knee fossa, you can choose to use diclofenac diethylamide latex or flurbiprofen gel paste for pain relief, but if the cysts are large in size, you need to consider surgery for removal. Patients with pain in the posterior fossa of the knee should go to a regular hospital in time to identify the cause of the disease and take targeted treatment under the guidance of a professional doctor. The above drugs need to be used under the guidance of a doctor, avoid self-medication.