Bone marrow edema is a manifestation of osteomyelitis, an infection and destruction of bone that can be caused by aerobic or anaerobic bacteria, mycobacteria and fungi. Osteomyelitis occurs in the long bones, in the feet of diabetic patients, or at sites of penetrating bone injury due to trauma or surgery. The most common sites in children are the long bones with good blood supply, such as the epiphyses of the tibia or femur. Boils, furuncles, sores, carbuncles and upper respiratory tract infections are the most common infectious diseases and are most likely to cause hematogenous osteomyelitis as a secondary infection. Therefore, the prevention of boils, sores, carbuncles and upper respiratory tract infections is very important to prevent the occurrence of osteomyelitis. 2. Traumatic infection, including infection after tissue injury and infection after bone injury, is also a common cause of osteomyelitis, so attention should be paid to active prevention in daily life. 3.For infectious diseases, early detection and timely treatment should be carried out. 4.Open fractures should be prevented from infection in the first place. Open fractures that have been internally fixed, once infection occurs and spreads to the medullary cavity, inflammatory infection often spreads along the intramedullary pin to both ends, and infection may also form under the skin at the site of intramedullary pin penetration or penetration, once it occurs, special attention should be paid to remove the internal fixation first to control the infection.