Silver-coated megaendoprostheses in a rabbit model—an analysis of the infection rate and toxicological side effects

Abstract

Deep infection of megaprostheses remains a serious complication in orthopedic tumor surgery. Despite the use of systemic and local antibiotic prophylaxis the reported infection rate is between 5% and 35%. Silver-coated medical devices proved their effectiveness in reducing infections. The objective of this study was to examine in vivo the antimicrobial efficacy and possible side-effects of a silver-coated megaprosthesis. In a first study, 30 rabbits (15 titanium versus 15 silver-coated Mutars ®—endoprostheses) were infected with Staphylococcus aureus. In a second study, toxicological side effects were analyzed in 10 rabbits with a silver-coated megaprosthesis. The silver group showed significantly ( p<0.05) lower infection rates (7% versus 47%) in comparison with the titanium group. Measurements of the C-reactive-protein, neutrophilic leukocytes, rectal temperature and body weight showed significant ( p<0.05) lower signs of inflammation in the silver group. The analysis of the silver concentration in blood (median 1.883 ppb) and in organs (0.798–86.002 ppb) showed elevated silver concentrations without pathologic changes in laboratory parameters and without histological changes of organs. In conclusion, the new silver-coated Mutars ®—megaprosthesis resulted in reduced infection rates without toxicological side effects, suggesting that this prosthesis might be a promising device in tumor surgery exhibiting antimicrobial activity.