It is very swollen after 1 month after meniscus surgery, the treatment is different according to the etiology, the common causes are premature activity, venous thrombosis, infection and so on, which need to be targeted treatment under the guidance of the doctor, such as proper rest, medication and so on. 1. Premature activity: If there is no sufficient rest after surgery and premature activity, the injury will not be recovered and local swelling will appear, you can take proper rest and elevate the lower limbs which will be beneficial to reduce the swelling. 2. Venous thrombosis: after meniscus surgery, it is usually necessary to wear a brace to avoid lower limb activities. Due to the lack of lower limb activities for a long time, the blood flow slows down, resulting in the formation of venous thrombosis in the lower limb, which requires thrombolytic therapy, such as rivaroxaban. 3. Infection: If the surgical port is infected after surgery, with fever, redness, swelling, pain and other symptoms, it is necessary to improve the blood routine, bacterial culture and other tests, and use antibiotics, such as cephalosporins for anti-infection treatment. The causes of swelling 1 month after meniscus surgery are more, if the symptoms continue to be unrelieved, it is recommended to consult a doctor in time, to clarify the cause of the disease, targeted treatment, do not blindly use drugs.