The aim of our research was to analyze the results of bacteriologic examination in patients with local and disseminated chronic osteomyelitis. We performed retrospective analysis of the results of bacteriologic examination of wound exudate in 80 patients who were admitted to the clinic of Irkutsk Scientific Center of Surgery and Traumatology for operative treatment of shinbone shaft fractures complicated with local and disseminated chronic osteomyelitis. We used common methods of mono- and bilocal osteosynthesis which resulted in different terms of fracture union and bone defect replacement. Bacteriologic examination of exudate from bone and soft-tissue wounds was performed in all patients at their admission to the clinic. In patients with local chronic osteomyelitis and with usual terms of fracture union, the most common were pure cultures (93. %) with dominant S. aureus (60 %). In patients with delayed fracture union, the most common were microorganism associations (55.5 ± 11.7 %). In patients with disseminated chronic osteomyelitis with usual terms of defect replacement, pure cultures were registered in 90 % of cases. In patients with delayed defect replacement pure cultures were found in 57,2 % of cases. Comparative analysis showed that in patients with delayed fracture union and defect replacement, bacterial associations were more common than in patients with usual terms of defect replacement. Preoperative bacteriologic examination showed that S. aureus was the dominant flora of wound exudate in patients with local and disseminated chronic osteomyelitis. Bacterial associations in wound exudate of patients with delayed fracture union and defect replacement is associated with significant circulation failure in affected extremity and is an unfavorable factor for reparative process disorder at chronic osteomyelitis.