A physical examination, MRI, and arthroscopic exploration will be able to determine if there is any damage to the meniscus of the knee. When the knee joint is damaged, the patient will have pain, limp leg and interlocking joints. In the examination of the knee joint medial or lateral pressure pain, do the knee joint flexion and extension, extrusion and grinding test pain and other positive signs, can be highly suspected of meniscus injury, can be further knee joint manipulation magnetic resonance examination. Through the knee magnetic resonance examination, the meniscus injury and the severity of the injury can be clearly defined, for the obvious injury can also be further arthroscopic investigation. Knee arthroscopy can directly under the mirror to observe the specific parts of the damage and the degree of damage. At the same time, it is also possible to treat the damaged meniscus, such as trimming and molding or meniscus suture. Patients are advised to seek prompt medical attention.