After posterior cruciate ligament reconstruction, patella displacement is mainly considered to be related to the structural disorder of knee joint, joint activity limitation or soft tissue adhesion, etc., which needs to choose the treatment plan according to the specific cause of the disease. 1. Structural disorder of knee joint: after posterior cruciate ligament reconstruction, if there is a structural disorder of knee joint, it will easily affect the position of patella, so it will lead to patellar subluxation, and it can be considered to be improved by joint loosening, and the patella can be appropriately pulled. 2. Restriction of joint movement: If the range of motion of the knee joint is affected by prolonged braking after posterior cruciate ligament reconstruction, it is easy to lead to the phenomenon of patellar downward movement, which needs to be improved by means of sports stretching to restore the range of motion of the knee joint and improve the position of the patella. 3. Soft tissue adhesion: after posterior cruciate ligament reconstruction, if there is a problem of soft tissue adhesion around the knee joint, which may lead to the phenomenon of patellar displacement, and it is not excluded that it needs to be treated by soft tissue release surgery. After posterior cruciate ligament reconstruction, in order to promote normal recovery, early attention should be paid to the braking rest, do not move the knee joint too early. In the later stage, it is necessary to carry out motor function exercise in a gradual and orderly manner to prevent the sequelae of motor dysfunction.