Patients with posterior cruciate ligament laxity, mostly due to direct violence or indirect external force to the knee joint, posterior cruciate ligament injury, posterior cruciate ligament laxity patients will have knee joint part of the loose, unstable or persistent pain, can carry out normal functional exercise, can restore the elasticity, toughness and length of the ligament. The specific recovery method is to instruct the patient to take a prone position, relax the whole body, the affected limb of the heel area close to the hip, adhere to 10-15 seconds, you can do 4-5 groups per day, each group can do 8-10, it is best to train under the guidance of a rehabilitation doctor, can prevent the occurrence of ligament injury.