The common people call it “knee”, and in medical science it is called “knee joint”. In the Henan dialect, it is also called “bu lao gai” (bu old gai). As the saying goes: “People get old before they get old legs”, the knee, which can be described as the larger and more complex flexion joint of the human body, is of great importance to people’s daily lives. In ancient times there is a criminal law called “Bin punishment”, refers to digging out the knee bone. The famous military man Sun Bin during the Warring States period was subjected to this punishment and changed his name from “Sun Bin” to “Sun Bin”. Kaifeng people have to intentionally say “ageless cover” (childish sound), giving the knee joint the title of eternal youth, which also explains the importance of the knee joint to human beings. What is the composition of our knee joint? The human body is made of flesh and blood, with bones, ligaments, muscles, blood vessels and nerves as its main components. The knee joint is the largest and most complex joint in the human body, and has a high chance of injury. Its bony structure consists of the medial and lateral femoral condyles, the medial and lateral tibial condyles, the fibula and the patella; the anterior and posterior cruciate ligaments (anterior and posterior cruciate ligaments), the medial and lateral collateral ligaments and the patellar ligaments; the medial and lateral menisci between the femoral and tibial condyles; the thin and loose joint capsule attached to the periphery of these cartilages; and the gap at the front of the knee joint is filled with fat. These are the main components of the knee joint. Many of the muscles of the thigh and calf also begin and end at the knee joint, and there are important blood vessels and nerves passing through the lower extremities behind it. The meniscus is composed of two crescent-shaped fibrocartilages located on the medial and lateral surfaces of the tibial plateau. The main function of the meniscus is to fill in between the femur and tibia, expand the contact surface of the femoro-tibial joint, have some elasticity, cushion gravity, play a role in protecting the joint surface, stabilize the knee joint, transmit load forces to the knee joint, and also assist in lubricating the joint. In recent years, the increased understanding of the meniscus has largely changed the principles of treatment for meniscal injuries. Anterior and posterior cruciate ligaments, medial, lateral and posterior collateral ligaments, and joint capsule The anterior and posterior cruciate ligaments (anterior and posterior cruciate ligaments), as well as the medial, lateral and posterior collateral ligaments and joint capsule ligaments of the knee. Together, they form a network of ligaments and capsules that are essential for maintaining the stability of the knee joint. As the saying goes: stability overrides everything else. It both limits the range of motion of the knee joint and guides the knee joint to follow a fixed pattern of motion. The anterior cruciate ligament prevents the tibia from shifting forward; the posterior cruciate ligament prevents the tibia from shifting backward; the tibial collateral ligament reinforces and limits knee hyperextension from the medial side; the fibular collateral ligament reinforces and limits knee hyperextension from the lateral side; the patellar ligament reinforces and limits knee hyperextension from the anterior side; 3. The patella protects the knee joint and prevents the quadriceps tendon from rubbing against the cartilage surface of the femoral condyles. It has the function of maintaining the stability of the knee joint in the semi-squatting position, preventing excessive knee adduction, abduction and extension and flexion activities, as well as the function of the carriage chain, increasing the knee joint rotation ability.