Release of antibiotics from the materials for postosteomyelitic bone defect filling

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.