Efficacy of Commercially Available Irrigation Solutions on Removal of Biofilms Grown on Porous Titanium Implants: An In Vitro Study.

Abstract

Periprosthetic joint infection (PJI) remains a major complication in orthopaedic surgery. A challenge in treating PJI is bacterial biofilm formation on implants, which confers a barrier to conventional antibiotic therapies and often necessitates implant removal and revision surgery. The goal of this study was to compare the efficacy of six commercially available irrigation solutions in decreasing bacterial load and disrupting biofilm formed on three-dimensional (3D)-printed porous titanium discs that are similar to the surface characteristics of TJA implants. An in vitro model with 3D-printed titanium discs was used. Staphylococcus aureus was cultured to induce biofilm formation on the discs. There were six irrigation solutions applied according to the manufacturer's instructions. The effectiveness of each solution in reducing bacterial load was measured by sonication and colony-forming unit (CFU) counts. Scanning electron microscopy (SEM) was employed to observe biofilm disruption and structural changes. When comparing groups, all had significantly fewer total CFUs after irrigation than after use of the chlorhexidine gluconate solution (P < 0.001). There were no other significant differences in the average total bacteria post-irrigation between the other groups. The SEM imaging revealed that the biofilm on the chlorhexidine gluconate-treated samples exhibited the least disruption when compared to the other groups. Although biofilm was not completely eradicated in any group, solutions like Solutions A and D demonstrated better disruption of biofilm architecture, with a reduction in the extracellular matrix. This study found that several commercially available irrigation solutions were more effective than chlorhexidine gluconate in reducing bacterial load and disrupting biofilm on porous titanium discs. However, none of the solutions completely eradicated biofilm, highlighting the limitations of irrigation alone in treating chronic PJI. While irrigation can be effective as a prophylactic measure, additional strategies are needed to effectively manage biofilm-associated infections in orthopaedic implants.