Radiology Cases Osteomyelitis

Description: If the bacteria are localized by, say, reduced flow, then they may have time to multiply and start a local infection, before being washed-out or destroyed in the blood. Trauma of bone, for example, may cause minor trabecular disturbance and a focus of poor circulation. Any pathology that produces bone infarcts will have a greater incidence of osteomyelitis. The transitional zones of the mataphyses are the most vascular, even in adults, and are the most likely site for infection. Infection destroys bone, will cross tissue boundaries and even cross cartilage plates. The proximity of joints to the metaphysis explains the incidence of septic arthritis. The spreading infection, bacterial toxins dead white cells and cellular toxins, pus, can spread out over the bone and elevate the periosteum. The periosteum has its own blood supply and will continue to make bone, while its elevation proceeds, the involucrum. This explains the "periosteal newbone" that is seen as a line exterior to the visible 'normal' location of cortical bone. As the infection proceeds, the diaphysis is eroded. Loss of blood supply to periosteal or cortical bone may produce infarction, the sequestrum.