Meniscus injuries usually have symptoms such as pain, swelling of joint effusion, joint popping and weakness of lower limbs. 1. Knee pain: the degree of pain varies according to the degree of injury. Small injuries have only mild pain, which is only aggravated by twisting or rotating movements, while serious injuries have severe pain accompanied by joint restriction. 2. Swelling of the knee joint with effusion: Meniscus injuries usually cause synovial inflammation, synovial exudate and joint effusion, which leads to swelling and stiffness of the joints. 3. Joint popping: when meniscus is acutely injured, there will be a tearing sensation or popping, and the sound can be heard when moving, which is called joint popping. 4. Weakness of lower limbs: patients can have pain in knee joint when walking and going up and down the stairs, and symptoms of knee joint tenderness and weakness of lower limbs. Quadriceps atrophy can occur. When the symptoms of meniscus injury appear, you should seek immediate medical attention and treatment as soon as possible to avoid irreversible damage.