The knee fell swollen consider joint effusion, fracture and other reasons, swelling can be taken physical therapy, medication, surgery and so on. 1. Joint effusion: knee injury will lead to blood in the joints, local swelling, after the injury to brake, reduce activities, local ice packs to prevent further aggravation of swelling, external Yunnan Baiyao aerosol to reduce swelling and pain. You can also apply sodium hepatic saponin or mannitol injection static point to reduce swelling treatment. If there is much fluid, you can also use a sterile syringe to draw out. 2. Fracture: after the fall, if the joint activity is limited, consider the possibility of fracture, need to take X-ray film to clarify the diagnosis, the fracture is not displaced line cast fixation, if the fracture has obvious displacement, the line of incision and reduction of internal fixation surgery. If your knee is swollen, first go to the hospital for a radiograph, further treatment after a clear diagnosis, do not blindly use medication.