Recently, a patient with patellar dislocation was admitted, who was still 14 years old and still growing. For such a patient with patellar dislocation, the use of bony surgery to correct the patellar dislocation is not appropriate because it will affect the patient’s growth and development. After the MRI and CT examination, it was seen that the patellar cartilage was damaged and collided with the lower end of his own thigh bone (medically called the distal femoral epicondyle) at the moment of patellar dislocation, most likely the patella’s own cartilage would have been knocked off, causing patellar cartilage damage. My article has previously addressed this issue for such an injury. The possibility of healing during the fresh period is high, and waiting until two weeks later, after the in situ formation of the bone scab is not very likely, and the surgical plan has to be redesigned. This time, as well, the patient came to our hospital immediately after the injury, and the treatment was still relatively timely. I would like to show you the photos before and after the surgery. Photo 1: The area in the middle of this photo is the area where the cartilage was knocked out, and if it is not repaired, arthritic symptoms will appear soon. The reason for this is simple: there is no joint surface left, and the consequences of this rough friction are severe. Photo 2: This is the piece of cartilage that was knocked out of the knee by using arthroscopic techniques to first find it in the knee cavity. Sometimes it is not always 1 piece, but several pieces may be knocked out. Once the cartilage is found and matched, it is held in place using special sutures like building blocks. Smaller bones are not easily fixed and do not have a cancellous bone surface, so they are removed. Once fixed, the articular surface comes out and the knee is then straightened and fixed for 1.5 months to allow it to grow and heal.