It is best to straighten the knee after an abrasion to avoid pulling on the wound site and promote healing, and you also need to take care of disinfecting the wound site to avoid infection. The knee should be straightened after an abrasion occurs because bending the knee will pull on the wound, causing tearing and delayed healing. Straightening the knee relaxes the skin at the knee, which promotes faster healing of the abrasion. After the knee abrasion, you also need to clean and disinfect the wound, first use saline to clean the wound, then use iodine povidone to disinfect the wound, after cleaning and disinfecting the wound can effectively avoid the wound from becoming infected. If the knee abrasion is serious, it is recommended to go to the hospital in time, complete the examination to clarify the cause of the disease, and then give targeted treatment or treatment.