The ACL is located within the knee joint and its main function is to prevent anterior and posterior tibial misalignment and rotational instability of the knee joint. Most patients have a history of acute knee trauma, with a tearing sensation within the joint at the time of injury, followed by pain and joint instability, and inability to complete ongoing movements. In individual cases, the ruptured ACL can become embedded in the joint space with typical joint locking (the joint is stuck) and the knee cannot be straightened. An ACL rupture of more than 6 weeks is considered an old injury. ACL rupture can result in significant joint instability, pain and swelling, and the patient may be afraid to jump, do sudden acceleration, make sharp turns and stops (basketball passing maneuvers, folding and running, etc.), or even feel the joint move wrongly when going downstairs. Complete rupture of the ACL should be treated surgically. At present, reconstructive surgery of the ACL under arthroscopy without cutting into the joint has been widely carried out and the technique is very mature. Arthroscopic treatment is less invasive and has a quicker postoperative recovery. The joint instability caused by ACL rupture can cause further damage to the meniscus and cartilage of the knee over time. Therefore, if an ACL rupture occurs, it should be treated with surgery as early as possible to avoid other secondary injuries.