Osteonecrosis can have a serious impact on the normal life of the elderly, as the occurrence of osteonecrosis in the elderly in daily life will often limit the elderly’s walking and running and jumping activities, resulting in the slow metabolism of the elderly, which seriously affects the health of the entire body of the elderly bones. Therefore, a clear understanding of the causes of dead bones in the elderly is quite important to prevent the occurrence of dead bones, thus avoiding the possibility of paralysis in bed. The causes of dead bone in the elderly: 1, age factor: the elderly as they grow older, the loss of bone calcium amount, the greater the improvement of necrotic bone occurs. 2, physical factors: the elderly with the decline in body function, the decline of immunity, resulting in poorer and poorer physical fitness, poor blood circulation, greatly increasing the probability of bone cell death, while increasing the occurrence of osteonecrosis disease 3, physical factors: according to clinical medicine, the elderly in the three high, cardiovascular sclerosis, atherosclerosis of the high incidence, resulting in blood vessel blockage, bone cell metabolism stopped, insufficient blood supply, leading to the occurrence of dead bone phenomenon. This leads to the occurrence of the phenomenon of dead bone. In order to improve the quality of life of the elderly in their later years, it is important to go to the hospital in a timely manner for physical examination to avoid the occurrence of osteonecrosis leading to the phenomenon of dead bones.