Medizinische Universität Graz Austria/Österreich - Forschungsportal - Medical University of Graz
Gewählte Publikation:
Merle, D.
On the creation of PMMA spacers containing ß-lactam antibiotics
Humanmedizin; [ Diplomarbeit ] Graz Medical University; 2018. pp. 66
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- Autor*innen der Med Uni Graz:
- Merle David Adrian
- Betreuer*innen:
- Kühn Klaus-Dieter
- Leithner Andreas
- Altmetrics:
- Abstract:
- INTRODUCTION: For decades, antibiotic loaded bone cement (ALBC) has been successfully used in surgical practise. In contrast to systemic antibiotic therapies, the use of ALBC enables high local concentrations and thus facilitates the total eradication of pathogens without risking systemic side effects. The Pro-Implant Foundation (PIF) periodically issues detailed and pathogen specific recommendations on which antibiotic agents are to be used as a PMMA supplement during one- or two-step revision protocols. Due to the rather fragile molecular structure of cephalosporin and ß lactam antibiotics along with the questionable compatibility with PMMA cements, those antibiotics are only rarely or not at all recommended. Therefore, it is crucial to evaluate if cephalosporin and ß lactam antibiotics are compatible with PMMA and how they impact on the mechanical and antimicrobial characteristics. MATERIAL AND METHODS: The samples were produced using PMMA cements (Palacos® R, Palacos® R+G, Copal® G+C, Copal® G+V) in combination with ampicillin (2,5% and 7,5%), piperacillin/tazobactam (11,25% and 22,5%) and cefuroxime (2,5% and 5%) in different concentrations. In order to assess the mechanical characteristics, tests according to ISO 5833 and DIN 53435 were performed. The antimicrobial efficacy was determined by inhibition zone assays in triplicates. RESULTS: All tested antibiotics could be successfully combined with PMMA without giving rise to significant inhomogeneities. The impact on the bending modulus (ISO 5833) was negligible, while significant differences could be observed for bending strength (ISO 5833) and Dynstat impact strength (DIN 53435). Generally, the higher the concentrations of the antibiotics were, the lower these values became. The antimicrobial efficacy showed strong strain-dependency, but was detectable for at least 28 days for the vast majority of tested strains. DISCUSSION: ß-lactam antibiotics can be effectively and safely combined with PMMA without critically decreasing stability of the cement or impeding antimicrobial activity of the antibiotic. Depending on the respective antibiogram, specific recommendations on the use of ß-lactam antibiotics can be made. This especially applies to cases were no allergies against the respective antibiotic are present and were reserve antibiotics would have to be used otherwise.