Synovitis effusion can be caused by a variety of different causes, such as degenerative arthritis, traumatic synovitis, infectious synovitis and rheumatoid synovitis, etc. Different diagnostic and treatment methods should be used to treat different diseases. 1. Degenerative arthritis: Degenerative arthritis is caused by the irritation of the synovial membrane due to bone hyperplasia, resulting in synovitis and effusion of fluid. Sodium vitrate can improve the microenvironment of the joints and promote the absorption of fluid. 2. Traumatic synovitis: Traumatic synovitis can occur due to meniscus injuries caused by twisting and external impact, resulting in fluid accumulation in the joint cavity, which can be treated by injecting dexamethasone after extracting the bloody fluid. 3. Infectious synovitis: If there is bacterial infection in the joint cavity, including tuberculous synovitis and bacterial synovitis, it should be treated with intra-articular injection of antibiotics such as cefuroxime sodium. 4. Rheumatoid synovitis: after diagnosis of rheumatoid or rheumatoid synovitis, intra-articular injection of dexamethasone and methotrexate can be used to treat the cause. Synovitis patients in the presence of effusion, should be actively under the guidance of the doctor treatment, to avoid inflammation exudation aggravation, resulting in adverse consequences.