Whether the meniscus is injured or not can be determined by symptoms, meniscus injury test and auxiliary examination. 1. Symptoms: acute meniscus injuries usually have a history of trauma, manifested by knee pain, swelling, popping or feeling stuck when moving, and other symptoms, and in severe cases, there is a limitation of knee joint movement. Chronic injury is often characterized by joint swelling, pain, popping, muscle atrophy in front of the thigh. 2. Meniscus injury test: such as knee joint overflexion test, knee joint over-extension test, rotational compression test, meniscus anterior horn compression test, meniscus gravity test and so on. These tests can be used to determine meniscus injury. 3. Auxiliary examination: such as X-ray, magnetic resonance examination, ultrasonic examination, arthroscopy, joint effusion examination, and so on. Among them, arthroscopy is the gold standard for the diagnosis of meniscus injury. If there is knee pain, swelling, etc., it is recommended to consult the doctor in time, make a clear diagnosis under the guidance of the doctor, and carry out regular treatment as early as possible.