Histology of osteosynthesis associated bone infection.

The introduction to this paper summarizes the small amount of information currently published on the histological changes that accompany posttraumatic osteomyelitis in man in addition to other information to aid understanding of this topic. The development of three cases of posttraumatic osteomyelitis and the histological analysis of important tissue areas harvested during debridement are described in detail. Two of the patients suffered from diaphyseal fractures, one of which was nailed and the other plated. The third patient had an epi-metaphyseal fracture, which was later plated with the additional use of an autogenous bone graft. The histological examination consisted of embedding the undecalcified tissue specimens in methylmethacrylate and cutting with a diamond saw or a special microtome. Bone necrosis, damaged soft tissue around it, and penetration of bacteria are the prominent etiological features for the onset of osteomyelitis. The distribution of bone necrosis depends mainly on trauma, the care of the surgeon, and the type of osteosynthesis. Loose dead bone and bone pieces demarcated by osteoclastic activity are transformed into sequestra surrounded by tissue that exhibits different infection activities according to the state of spontaneous development or treatment. Remodeling of bone necrosis from the living bone is slow and depends on many factors. New bone formation is mainly subperiosteal, embedding osteomyelitic areas if the periosteum is not destroyed.