Medizinische Universität Graz Austria/Österreich - Forschungsportal - Medical University of Graz
Gewählte Publikation:
Kunzi, J.
Comparative analyses with drug-loaded cements for the usage in revision arthroplasty
Humanmedizin; [ Diplomarbeit ] Graz Medical University; 2019. pp.
[OPEN ACCESS]
FullText
- Autor*innen der Med Uni Graz:
- Betreuer*innen:
- Kühn Klaus-Dieter
- Leithner Andreas
- Altmetrics:
- Abstract:
- Introduction The therapy with local antibiotics by periprosthetic joint infections in combination with a one-stage or two-stage exchange of the prosthesis is essential for a successful eradication of the bacteria [Neut et al. 2007]. However, studies and case reports show that a recolonization and formation of biofilms is also possible by the use of gentamicin-containing polyacrylmethacrylates (PMMA) [Schmolders et al. 2014; Thornes et al. 2002]. This investigation tested the in vitro effect of different drug-loaded bone cements which were used in revision surgery against different microbes with agar diffusion tests. Material/Methods Eleven drug-loaded (0.5-2.5 g antibiotics in 40 g powder) cements were categorized in five groups, pressed in moulds and incubated in 20 ml phosphate buffered saline solution under sterile conditions. The cement moulds were put out, dried and inserted in a new solution after 1 h, 24 h, 7 d, 14 d, 21 d, 28 d and 42 d. Mueller-Hinton agar plates were spread with MRSA, E. coli, Pseudomonas aeruginosa or Cutibacterium acnes and a hole with a diameter of six millimeters was punched in the centre of each plate and filled with 30 µl of one of the elution fluids. After at least 24 hours incubation by 37 degrees Celsius, the zones of inhibition were measured with a ruler. Each bone cement was tested three times against every bacterium. The inhibiting areolas were documented in tables, graphs and pictures. Solely descriptive statistics were calculated because of the small number of test repetition. Results Group A contained PMMAs with aminoglycosides. None of the cements reached any effect against MRSA. Palacos® R+G showed always peak values and was the only one that had an antibacterial efficacy of 42 days. Simplex® HVG, Hi-Fatigue® G and BonOs® R Genta reached good zones of inhibition until the 28th day while Simplex® T showed inhibiting areolas for 14-21 days and CMW 1 G only for 24 hours to 7 days. Cements of group B with gentamicin and clindamycin also showed no effect against MRSA. The inhibition zones of Refobacin® Revision and Copal® G+C with Cutibacterium acnes were very similar and reached a peak value on the seventh day with 63.7 mm ± 1.5 and 63.3 mm ± 2.9, respectively. Simplex® E+C (group C) reached no effect against Pseudomonas aeruginosa and MRSA. There were significant differences between the PMMAs in group D which contained gentamicin and vancomycin. Vancogenx® showed an effect against E. coli until day seven and against MRSA until the 21st day at most. Copal® G+V had a good antibacterial efficacy over the whole tested time period with both tested bacterial strains. Group E with Copal® G+C showed similar results like in the tests against Cutibacterium acnes of group B. Discussion The results showed clear differences between the tested PMMA cements. The choice of the bone cement should be made in a considerate way, because the antibiotic elution of the various brands obviously differs very much which can lead to different antibacterial efficacy. Furthermore, the study shows that the concentration of antibiotic in the cement powder does not allow any interpretation to the antibacterial efficacy. The quantity of drug release and thereby the microbiological efficacy is important for recommendations of the PRO-IMPLANT-Foundation for admixture in revision surgery [Renz and Trampuz 2018].