Chronic osteomyelitis in a new rabbit model

Dogs, rats, and rabbits are the most suitable species to induce chronic ost eomyelitis and to study different methods of treatment. In rabbits, the inc idence of and mortality from Staphylococcus aureus-induced osteomyelitis of the tibia depends on the method of prelesions and the amount and virulence of species-specific bacteria used. In this study two different lesions wer e combined simultaneously in the medullary canal of the femurs by aspiratio n of bone marrow, leaving the insertion needle in situ. A sclerosing agent was then inoculated followed by 300,000 bacteria of a rabbit-derived S. aur eus strain to initiate infection. With this method, the incidence of chroni c progressive osteomyelitis of the femur was increased to 100%. A relativel y low mortality was observed, probably due to a lower number of inoculated bacteria as compared to other rabbit models described. The incidence of acu te to chronic osteomyelitis was diagnosed by local signs, x-rays, microbiol ogical recovery, and gross pathology of the femur. Initial fever, weight lo ss, abscess formation in soft tissues, and pain on palpation characterize t he clinical features in the course of development of this chronic disease.