The bone can still move after posterior cruciate ligament surgery, which is caused by ligament laxity, or combined with anterior cruciate ligament injury and lateral collateral ligament injury. At present, for the complete rupture or most of the rupture of the posterior cruciate ligament, the minimally invasive knee arthroscopic surgery is usually taken for reconstruction, and the purpose of reconstruction is to restore the original anatomical structure of the knee joint and maintain the stability of the knee joint, avoiding the phenomenon of sliding of the bones of the knee joint. Instability of the knee joint will cause weakness and difficulty in walking on the one hand, and aggravate the wear and tear of the articular cartilage on the other. If the local ligaments are still loose after surgery, the bones may still move. In addition, if the bone can still move after posterior cruciate ligament surgery, it cannot be ruled out that there are injuries and ruptures of the anterior cruciate ligament and lateral collateral ligaments, which will also affect the stability of the knee joint, resulting in the bone can still move. In conclusion, if the bone can still move after posterior cruciate ligament surgery, it is recommended to consult an orthopedic surgeon for further diagnosis and treatment.