Osteomyelitis is an infection in a bone. Infections can reach a bone by traveling through the bloodstream or spreading from nearby tissue. Infections can also begin in the bone itself if an injury exposes the bone to germs.
In children, osteomyelitis most commonly affects the long bones of the legs and upper arms. Adults are more likely to develop osteomyelitis in the bones that make up the spine (vertebrae). People who have diabetes may develop osteomyelitis in their feet if they have foot ulcers.
Once considered an incurable condition, osteomyelitis can be successfully treated today. Most people require surgery to remove parts of the bone that have died — followed by strong antibiotics, often delivered intravenously, typically for at least four to six weeks.
Source: https://www.mayoclinic.org/diseases-conditions/osteomyelitis/symptoms-causes/syc-20375913