There are about 206 bones in the human body, which are mainly composed of bone tissue and richly distributed with blood vessels, lymphatic vessels and nerves. Bone is composed of organic matter, inorganic matter and water, bone is covered with periosteum and contains bone marrow, and bone mass is divided into dense bone and cancellous bone. Dense bone has strong resistance to compression and distortion, while cancellous bone is mainly found at the end of the stem scale and is filled with red bone marrow. The bones of the human body have many functions such as protection, support, movement and hematopoiesis. The proportion of organic and inorganic matter in bone changes gradually with age. In the bone tissue of young children, the proportion of inorganic matter accounts for about 1/2 of the backbone, and in adulthood, organic matter accounts for about 1/3 of the backbone and inorganic matter accounts for 2/3 of the backbone, and in the elderly, the inorganic matter will further increase. As a result, the bones of young children are pliable and easily deformed, and may break but not break when subjected to violence. In the elderly, the bone is easily brittle and less elastic, which, together with osteoporosis, makes it susceptible to fracture.