The cruciate ligaments may refer to the anterior cruciate ligament and the posterior cruciate ligament of the knee. When they are mildly injured, it is considered that a small number of fibers of the cruciate ligaments are torn due to trauma to the knee, and there is no joint instability. 1. Anterior cruciate ligament injury: It is mainly caused by external force, resulting in strong abduction or hyperextension of the knee joint. In mild injuries, patients may experience significant pain and swelling in the knee joint, but the knee joint is stable. 2. Posterior cruciate ligament injury: mostly seen in the upper end of the tibia of the knee joint is hit by the backward force, mild injury is only a slight tear of the ligament fibers, the patient can have obvious pain and swelling of the knee joint, will not affect the stability of the knee joint. It is recommended that patients go to the hospital in time to improve the auxiliary examination, in order to clarify the condition, mild injury can be given conservative treatment, need to be treated by a professional physician.