Introduction The search for materials for bone defect filling that would provide a release of antibiotics in therapeutic levels over a long period is a pressing issue in the treatment of patients with osteomyelitis.The purpose of the work was to compare the kinetics of antibiotic release from materials based on polyurethane polymers for filling post-osteomyelitic bone defects.Materials and methods A comparative in vitro analysis of the kinetic release of cefotaxime, vancomycin, and meropenem from two materials was performed: one was based on polyurethane polymers (RK series) and the other on polymethyl methacrylate (PMMA series). In each series, antibiotics were added to the original materials in three proportions: polymer/ antibiotic — 10:1 (group 1); 10:0.5 (group 2), and 10:0.25 (group 3). The samples were incubated in 10 ml of saline at 37 °C. The incubation solution was changed daily during the first week, and then once a week. Six samples were incubated in each group.Results It was revealed that the volume of eluted cefotaxime in the PMMA series was higher than in the RK series for all antibiotic concentrations. In turn, for vancomycin and meropenem, it was observed only for group 1 samples. For groups 0.5 and 0.25, a larger volume of released antibiotics was noted in the RK series than in the PMMA series. It was found that in the RK series, the release of vancomycin and cefotaxime in an effective (therapeutic) concentration was more prolonged. In the RK series, there was prolonged release of effective concentrations but in a smaller volume of released antibiotic than in the PMMA series.Discussion Each material showed its own antibiotic elution profile and each of them may have its own indications. The RK-based material has advantages in terms of the duration of antibiotic elution in therapeutic doses.Conclusion The release of the studied antibiotics in effective concentrations from the material based on polyurethane polymers is longer than from the PMMA-based material.

Purpose of the analytical review — to evaluate the application experience of bone xenografts in trauma and orthopaedics surgery. Methods. Data search was performed in the electronic databases of PubMed and eLIBRARY with depth of 20 years. Results. The authors identified 13 papers which described the application experience of bone xenografts in trauma surgery and orthopaedics. The highest efficiency (from 92 to 100%) was reported for cases of xenografts use to replace defects in intraarticular fractures and revision arthroplasty. Unsatisfactory outcomes were related to cases with no integration and graft rejection. The least efficiency (from 41,9 to 46,1%) was reported in reconstructive foot surgery. No effect of bone xenografts was observed for replacement of defects in cases of pseudoarthrosis. The most frequent complication was graft material infection. The summarized literature data provided the calculated share of complications following xenograft use of 7,53% (18 out of 239 cases, CI 5-95%, 4,53-11,21). Two areas were identified for improvement of technical and biological properties of bone xenografts: 1. Modification of original xeno-matrix (enhancement of purification technique, alteration of structure of chemical composition of the bone matrix); 2. Augmentation of matrix volume by additional elements (biologically active agents, stem cells). It’s noted that demand for xenografts in traumatology and orthopaedics can increase after refining and expanding the indications for clinical use. Conclusion. Bone xenografts used in the modern trauma surgery and orthopaedics to replace bone defects in revision arthroplasty as well as in certain fracture types. Such material is relatively safe and its ability to be modified allows to improve its biological properties.

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