The structure of bone includes three parts: bone, bone membrane, and bone marrow. Bone is connected to bone to form the skeleton, which can mainly assist the body to complete the movement and protect the important organs of the body, such as the heart, brain, kidney, etc., and also has the role of supporting the weight, which is the key to constitute the human body scaffold.1. Bone: composed of bone tissue, can be divided into dense bone and osteophyte. Osteodense structure is dense, strong resistance to compression, hard texture, and distributed on the surface of the bone; osteophyte is crossed by the arrangement of bone trabeculae, the structure is more lax, and the texture is more brittle; 2, periosteum: covered in the bone surface other than the joint surface, mainly composed of fibrous connective tissue. The periosteum is divided into an inner layer and an outer layer, with the outer layer being denser and the inner layer being lax. The periosteum is rich in blood vessels, nerves and lymphatic vessels, which can provide nutrition for bone and play an important role in bone nutrition and regeneration; 3. Bone marrow: it is a soft tissue that fills the bone marrow cavity and the cancellous space of bone, and is divided into red bone marrow and yellow bone marrow. Red bone marrow contains red blood cells, which are red in color and have hematopoietic and immune functions. Yellow bone marrow is mainly fatty tissue, which appears yellow and has no direct hematopoietic function, but can be converted to red bone marrow with hematopoietic function when the body is severely anemic. The bone marrow of infants and children is red marrow, and after the age of 5, the red marrow in the long bones will gradually become yellow marrow, but the red marrow is always present in the epiphysis of irregular bones such as vertebrae and iliac bones.