High-dose antibiotic-loaded acrylic cement (ALAC) is used for managing peri-prosthetic joint infections (PJIs). The marked increase in resistant high-virulence bacteria is drawing the attention of physicians toward alternative antimicrobial formulations loaded into acrylic bone cement. The aim of this in vitro study was to determine the elution kinetics of 14 different high-dose ALACs. All ALAC samples showed a burst release of antibiotics in the first hour, progressively decreasing over time, and elution curves strictly adhered to a nonlinear regression analysis formula. Among aminoglycosides, commonly seen as the most appropriate antibiotics to be loaded into the bone cement, the highest elution rate was that of tobramycin. Among the glycopeptides, a class of antibiotics that should be considered to treat PJIs because of the prevalence of aminoglycoside resistance, vancomycin showed better elution than teicoplanin. Clindamycin, which can be associated with aminoglycosides to prepare ALACs and represents a useful option against the most common pathogens responsible for PJIs, showed the highest absolute and relative elutions among all the tested formulations. A noticeable elution was also detected for colistin, an antibiotic of last resort for treating multidrug-resistant bacteria. The current study demonstrates theoretical advantages in the preparation of ALAC for some antibiotics not routinely used in the clinical setting for PJIs. The use of these antibiotics based on the infecting bacteria sensitivity may represent a useful option for physicians to eradicate PJIs. In vivo testing should be considered in the future to confirm the results of this study.

Coloured bone cements have been introduced to make the removal of cement debris easier at the time of primary and revision joint replacement. We evaluated the physical, mechanical and pharmacological effects of adding methylene blue to bone cement with or without antibiotics (gentamicin, vancomycin or both). The addition of methylene blue to plain cement significantly decreased its mean setting time (570 seconds (SD 4) vs 775 seconds (SD 11), p = 0.01), mean compression strength (95.4 MPa (SD 3) vs 100.1 MPa (SD 6), p = 0.03), and mean bending strength (65.2 MPa (SD 5) vs 76.6 MPa (SD 4), p < 0.001) as well as its mean elastic modulus (2744 MPa (SD 97) vs 3281 MPa (SD 110), p < 0.001). The supplementation of the coloured cement with vancomycin and gentamicin decreased its mean bending resistance (55.7 MPa (SD 4) vs 65.2 MPa (SD 5), p < 0.001).The methylene blue significantly decreased the mean release of gentamicin alone (228.2 µg (SD 24) vs 385.5 µg (SD 26), p < 0.001) or in combination with vancomycin (498.5 µg (SD 70) vs 613 µg (SD 25), p = 0.018) from the bone cement. This study demonstrates several theoretical disadvantages of the antibiotic-loaded bone cement coloured with methylene blue.

The use of fast or standard setting cement does not produce any difference in the quality of the radiologic cement mantle in the short-term. Both cements comply with ISO 5833 requirements.

The use of fast or standard setting cement does not produce any difference in the quality of the radiologic cement mantle in the short-term. Both cements comply with ISO 5833 requirements.

No abstract