The meniscus is an important part of the knee joint. It is a tough, crescent-shaped disc, two for each knee joint, on the inner and outer sides, which moves with the femur above or the tibia below according to different movements in the knee joint, acting as a cushion to absorb shock, reduce contact stress and maintain joint stability. Meniscal injuries are a very common type of sports injury, often caused by uncoordinated joint activity, such as kicking a soccer ball in the air or against the foot, or tripping and falling during running and other knee sprains, resulting in the meniscus getting stuck between the femur and tibia, causing a tear. If other conditions exist at the same time, such as long-term squatting labor, original ligament injury, or original discoid meniscus, it is more likely to cause a tear. Older adults are also prone to tears due to degenerative aging of the meniscus, and these tears can be caused even without obvious trauma. After meniscal injury, the most common symptom is pain when walking or exercising, the pain can be on one side of the joint or behind the joint, or it can occur when the joint extends and flexes to a certain position; many patients can experience the sound of “clicking” when squatting or walking, often at a relatively fixed angle; sometimes it can also Many patients may experience a “clicking” sound in the joint when squatting or walking, often at a relatively fixed angle; sometimes the joint may suddenly become stuck and immobile or the joint may suddenly become weak, affecting the quality of life. More seriously, the torn meniscus can also pull the synovial tissue during joint activities, wear out the joint cartilage, cause chronic synovitis that is extremely difficult to cure, and accelerate joint degeneration, making arthritis appear earlier. Therefore, meniscal tears must be diagnosed and treated as early as possible. Because the meniscus does not appear in the X-ray film, the X-ray examination does not detect the meniscus injury, especially in the acute stage of the injury, the swelling and pain of the joint affect the doctor’s physical examination and diagnosis, so the meniscus injury is often missed, losing the time for treatment and delaying the condition. The development of modern medicine allows us to use MRI for early diagnosis of meniscal injuries. For some cases that are difficult to diagnose, arthroscopic techniques can be used to accurately diagnose meniscus injuries. Treatment for meniscal tears is surgical or non-surgical. For small tears in the vascular zone, they can be treated with external fixation brakes such as casts and knee braces. All kinds of injuries other than these require surgical treatment. In general, most meniscal tears that cause symptoms require surgical treatment. In the past, when meniscus tears were found, they were often removed in their entirety, which provided temporary relief, but lost the meniscus-protected joint. It can develop into arthritis in just a few years. Therefore, current surgeries use arthroscopic partial meniscus removal or suture techniques to preserve as much normal meniscal tissue as possible and reduce the impact on joint function.