Post-operative swelling of the knee joint is quite common after arthroscopic meniscus surgery, ACL reconstruction, and post-operative swelling of the ankle joint, shoulder joint and extremity fractures. A. Injury to the synovial tissue within the joint caused by the surgery itself, resulting in synovial exudation, swelling and fluid accumulation; B. Intraoperative stretching and blunt stripping of soft tissues, resulting in postoperative soft tissue reactive swelling; C. Inflammatory reaction within the knee joint itself or postoperative reactive inflammation causing or further aggravating swelling; D. The large amount of saline used during the arthroscopic surgery itself to flush and expand the joint cavity; the saline is absorbed by the nearby soft tissue cells, resulting in swelling; E. The swelling of the knee joint after the surgery; E. The swelling of the knee joint after the surgery. Post-operative swelling can lead to limited knee movement, delayed wound healing, dehiscence, wound pain, and painful knee movement, thus hindering the post-operative rehabilitation of the knee joint! The best way to deal with post-operative swelling is to apply ice, compression bandages, or elastic knee pads. Many patients ask: I have followed the doctor’s instructions, iced and applied pressure, but why is the swelling not effective and still getting worse? One of the most important reasons is the incorrect method of icing, not using professional ice packs, some may simply use ice cubes or ice mineral water bottles on the knee, so the full contact area with the knee joint is small and the effect is limited, so the effect is not ideal! At the same time, the correct ice with the use of elastic knee pads, or elastic bandages, can make the effect twice as good!