The anterior cruciate ligament is an important stabilizing structure of the knee joint that is highly susceptible to injury and, in severe cases, rupture during sports activities or other sports. After an ACL rupture, although the patient walks quite normally, he or she is unable to perform sports activities such as running, jumping, and even less able to run, stop, or turn and run. More importantly, after ACL rupture, the task of stabilizing the knee joint is “transferred” to the meniscus (especially the medial meniscus) and the spherical structure of the joint surface to complete, so it is very easy to cause secondary meniscal damage and articular surface cartilage damage, which can directly lead to the “scrapping” of the injured joint Therefore, it is very easy to cause secondary meniscus damage and articular surface cartilage damage, which can directly lead to the “failure” and early “retirement” of the injured joint. Therefore. Anterior cruciate ligament rupture must be treated in a timely manner, what is considered timely? From the first day after the injury to one month after the injury surgery can be considered timely, the later the treatment, the more “mending” the meaning of the sheep. The ACL rupture must be treated surgically, because the ACL rupture suture treatment is ineffective, must be a kind of surgery called “ACL reconstruction”. Reconstruction means that a new ACL is made to replace the patient’s original ligament. The procedure is simple: a hole (bone tunnel) is drilled in the femoral and tibial ends of the knee joint, a replacement ligament is introduced into the joint, and the new ligament is fixed to the femoral and tibial ends at the appropriate location. The ligament substitutes are autologous tendons, allograft tendons, and artificial ligaments. Autologous tendons are taken from less functionally important tendons in the patient’s body, but if the patient’s own tendons are too thin or too many ligaments need to be reconstructed, an allograft tendon is required, the latter having the disadvantage of a slightly longer recovery period and the theoretical possibility of disease transmission. Artificial ligaments are not routinely used in clinical practice because they are non-biological materials and have problems of fatigue rupture. There are many materials for fixing ligaments, including interface extrusion screws, sutured overturned plates, cross-over nails, and pile nails, all of which are relatively expensive. In the surgery of ACL reconstruction, one ACL is usually reconstructed, which is also called “single-bundle reconstruction”, and two at the same time, which is called “double-bundle reconstruction”, the latter procedure is more complicated and the cost of the patient is significantly higher, but some scholars believe that double-bundle reconstruction is closer to normal. However, some scholars believe that double-bundle reconstruction is closer to the normal anatomy and physiology, so the surgical result is better than single-bundle reconstruction. Post-operative rehabilitation of the ACL is a lengthy process, with full recovery taking 1 to 1.5 years. The rehabilitation process includes three components: muscle strength recovery, joint mobility exercises, and proprioceptive training. Through systematic rehabilitation, we aim to achieve motor functions such as walking, squatting, going up and down stairs, running and jumping on schedule after surgery. Complications such as laxity of the reconstructed ligament, joint adhesions, muscle atrophy and pulmonary infarction should be avoided as much as possible. The literature reports that approximately 15% of patients have unsatisfactory results after ACL reconstruction, which is more often due to untimely and inappropriate postoperative rehabilitation than to surgical technique. In addition, each patient has a different time of injury and a different combination of injuries at the same time, so the postoperative results may vary greatly. For example, an ACL injury combined with meniscus and articular surface cartilage injury may affect the overall outcome of ACL reconstruction surgery even if it was treated at the same time.