It’s not that the “periosteum” is broken as you said, but that the articular surface of the knee joint has been worn and degenerated due to old age. Medically, it is called knee osteoarthritis. In the advanced stages of this disease, surgical treatment is necessary. Surgery involves removing the damaged joint surface and replacing it with an artificial joint surface. This is the greatest development in orthopedics today. It is a very mature technology, just like putting a brace on a bad tooth. After the surgery, the patient's joints will be reborn. If, as you said, you can no longer walk after "replacing the bone bowl", wouldn't the doctor be doing harm to people? ! However, this surgery can currently only be performed well in hospitals specializing in joint surgery in central cities. As long as it is performed by joint surgery experts from large hospitals above the provincial capital, there will be no problem. Professor Jin Qunhua from the Department of Joint Surgery of Ning Medical Affiliated Hospital is your best local joint surgery expert. He is also a famous joint surgery expert in China. I suggest you take the old man to see him.