Background. Metals used for the manufacture of various implants for traumatology have all the necessary mechanical properties, but these materials are able to oxidize. In comparison, carbon has excellent biocompatibility. Carbon-carbon composite material (CCCM) is 2-4 times lighter than a similar metal implant, has a stiffness and modulus of elasticity close to similar indicators of a human bone, not prone to the effect of fatigue stress, and is characterized by chemical resistance in the body and high biocompatibility. Objective. The purpose of this work was to evaluate the features of bone regeneration according to pathomorphological analysis in an experiment on animals. Material and Methods. Carbon-carbon composite material for intromedular osteosynthesis after experimental fracture on white outbred male Wistar rats (n=18) was used in the experiment. A stainless steel rod (n=18) was used for control. Subsequently, rats of both groups were kept in standard vivarium conditions. Results. Histological examination revealed that the use of implants with CCCM did not disrupt vascularization and angiogenesis in the fracture zones. During the analysis of the contact of bone tissue and implant material, it was determined that in the larger area of ​​the perimeter of the pin with CCCM, a newly formed bone was located directly on its surface, filling its irregularities. In the case of the use of stainless steel rods, a significant number of lymphocytes were accumulated around the newly formed blood vessels directly adjacent to small hemorrhages, which were always observed at the fracture site. Conclusions. Regeneration of an experimental rat femur fracture after osteosynthesis with carbon-carbon composite implants did not differ significantly from fracture fusion after osteosynthesis with a stainless steel implant.

Background. In Ukraine, there has recently been an increase in the number of limb bone fractures among the population, in particular, due to increase in the number of elderly people, which is associated with the development of age-related osteoporosis and fragility of bones. Therefore, the use of artificial implants in traumatology is becoming increasingly important. The search for new bioinert and biodegradable materials, that are capable of providing rapid fracture consolidation and do not require repeated surgical intervention, continues. Objective. To elaborate a model for the research of using carbon-carbon composite nail for intramedullary osteosynthesis in laboratory rats with fractures of femur and tibia in norm and with experimental osteoporosis. Methods. The work investigated the lower limbs of 6 groups of Wistar rats. The first part of the study involved 4 groups of rats with modeled tibial fracture with subsequent osteosynthesis in norm and with experimental osteoporosis. The second part of the research included two groups of laboratory rats with modeled femur fracture. In both parts we used metal injection needle, as well as carbon-carbon composite nail for osteosynthesis. Results. All animals underwent surgery well, stepped on the injured limb. X-ray examination after the osteosynthesis demonstrated satisfactory reposition of the fragments. One month after modeled fracture in rats with experimental osteoporosis a violation of the normal consolidation of the fracture was observed, especially in the group where carbon-carbon composite nails were used for osteosynthesis. Further, until the 180th day after the surgery there were no peculiarities, function of the limbs was restored, mainly without expressed angular deformities. Conclusion. The above mentioned model was successfully elaborated for the research of using carbon-carbon composite nail for intramedullary osteosynthesis in laboratory rats with fractures of femur and tibia in norm and with experimental osteoporosis.