Recovery from knee meniscus injury cannot be signaled by the disappearance of joint effusion. Whether the knee meniscus injury is treated surgically or conservatively, as the meniscus heals and the inflammation in the joint cavity decreases, the amount of joint fluid will gradually decrease, but it will not disappear completely, so the disappearance of joint fluid cannot be taken as a sign of healing of the meniscus injury. Whether the meniscus is healed should be considered in conjunction with the patient’s symptoms, physical examination and imaging. In normal knee joints, there is a small amount of joint fluid, which lubricates the articular cartilage and protects the joint surface. When there is inflammation in the joint, such as trauma, infection, gout, etc., it will lead to an increase in the joint fluid in the joint cavity, and a larger amount of joint fluid will lead to swelling, soreness and other discomfort in the joint. After knee meniscus injury, you need to standardize the treatment under the guidance of a professional doctor.