Low lubricating fluid in the knee joint may be caused by knee osteoarthritis, degenerative disease, meniscus injury, etc. It is necessary to actively treat the primary disease to prevent the loss of synovial fluid, and at the same time lubricate the joint with medication. 1. Treatment of the primary disease: first of all, go to the hospital to clarify the cause of the disease, and then treat the cause of the disease. Knee arthritis can also be treated symptomatically to control inflammation and slow down the condition. Degenerative diseases are mainly treated with the purpose of relieving pain, improving joint function and slowing down the degeneration of joints. 2. Medication: Oral medication to protect articular cartilage, such as glucosamine sulfate capsule or glucosamine hydrochloride capsule, or intra-articular injection of sodium vitrate to increase lubrication. In addition, it should reduce the weight bearing and excessive exercise of the knee joint to avoid further wear and tear of the articular cartilage. It is recommended to go to the hospital in time, to clarify the cause of the disease, and to carry out treatment under the guidance of the doctor, avoiding the blind use of drugs by oneself.