DefinitionOsteomyelitis is an acute or chronic bone infection.Causes, incidence, and risk factorsBone infection can be caused by bacteria (more common) or fungi (less common).Infection may spread to a bone from infected skin, muscles, or tendons next to the bone, as in osteomyelitis that occurs under a chronic skin ulcer (sore).The infection that causes osteomyelitis can also start in another part of the body and spread to the bone through the blood.A current or past injury may have made the affected bone more likely to develop the infection. A bone infection can also start after bone surgery, especially if the surgery is done after an injury or if metal rods or plates are placed in the bone.In children, the long bones are usually affected. In adults, the feet, spine bones (vertebrae), and