Fluid in the bone generally refers to the presence of bone marrow edema or the presence of fluid in the joint cavity. In this case, the following treatment measures are generally taken: 1. For most cases of bone marrow edema and mild joint effusion, conservative treatment is preferred. Conservative treatment requires patients to maintain strict braking and rest during the treatment period, and not to do strenuous activities during this period to avoid aggravating the effusion. In addition to this, anti-inflammatory, anti-swelling, and pain-relieving drugs should be used, and the most commonly used non-steroidal drugs are nimesulide, together with sodium heptaerythroside, which is an anti-swelling drug. In addition, acupuncture, tui na, Chinese herbal fumigation, cupping, electrocautery and heat treatment can be used as supplementary treatment. 2. If there is more fluid in the joint cavity, joint fluid aspiration or joint cavity cleaning can be performed. Joint cavity cleaning is mainly done through arthroscopic surgery to explore, repair and irrigate the joint cavity.