DYNAMICS OF MORPHOLOGICAL CHANGES IN FRACTURE SITES IN VICTIMS WITH THORACIC TRAUMA AND FLAIL CHEST

Objectives - to improve the treatment results in patients with a closed chest injury complicated by the flail chest through the evaluation of the pathomorphological changes in the fracture sites on the background of their stabilization. Material and methods. The study is based on the autopsy protocols of 402 victims, whose primary cause of death was a closed chest injury with multiple rib fractures. In total 289 histological specimens were studied, including 82 samples taken from the rib fractures zones of the persons with a flail chest died in different periods after the injury. Depending on the time passed from the injury till death, there were identified 5 groups of patients. So It was possible to reveal the consistency of the evolution of morphological changes in the zone of rib fractures on the 1st, 2nd, 5th, 14th, and 21st day after the injury, with preserved breathing without stabilizing the rib cage. Results. We found out that on the 1st, 2nd, 5th day there were no morphologically significant changes in the fracture zone, aimed at its stabilization. With breathing preserved for more than 5 days, there was a delay in the primary callus formation and enhanced bone resorption in the fracture site. Osteoblasts activation, which manifests the proliferation of cellular elements in fragmentary rib fractures, occurred 7-9 days later than in a single fracture. It was conditioned by the persistent "floating" of the rib fragments which impacted the newly formed trabeculae of bone and forced them to rearrange twice during the bony callus formation. The increased time of the rib fractures repair aggravated the lung injury, contributed to the development of pneumonia and purulent-septic complications detected posthumously which, in their turn, were the primary cause of deaths. Conclusion. In 17.4% of victims with severe chest injury and flail chest the death is conditionally preventable. The crucial requirement of the effective treatment of patients with the thoracic trauma and flail chest is the usage of various methods of the thoracic cage stabilization.