LAUSR

BACKGROUND/HYPOTHESIS Treatment of periprosthetic joint infection (PJI) is complicated by the presence of residual biofilm, which resists eradication due to bacterial adherence to orthopedic implants. The purpose of this study was to compare BactisureTM (Zimmer Biomet, Warsaw, IN, USA), povidone-iodine (Betadine), and chlorhexadine gluconate solution (Irrisept®) (Irrimax Corp., Gainesville, FL, USA) on reducing biofilm formation of Staphylococcus aureus (S. aureus), Staphylococcus epidermidis (S. epidermidis), and Cutibacterium acnes (C. acnes) inoculated on cobalt-chrome, titanium and stainless-steel discs, representing metals commonly used for shoulder arthroplasty. The hypothesis was that there would be no significant difference in reduction in biofilm between the three topical adjuvants. METHODS Strains of S. aureus (ATCC 35556), S. epidermidis (ATCC 35984), and C. acnes (LMG 16711) were grown on the cobalt-chrome, titanium and stainless steel discs. For each strain, discs were divided into four groups: (1) control, (2) povidone-iodine (Betadine), (3) chlorhexadine gluconate (Irrisept®), and (4) BactisureTM. Bacteria was grown on 5% sheep's blood agar plates. Biofilm eradication was quantified using adenosine triphosphate (ATP) bioluminescence and compared to controls 48- and 72-hours post-implementation of the topical adjuvant. RESULTS At 72-hours post-implementation of topical adjuvant, a statistically significant reduction in colony-forming units (CFUs) was observed for all topical adjuvants across all tested metals, as compared to their respective control. With respect to the topical adjuvants themselves, BactisureTM more consistently demonstrated the most significant reduction in CFUs across all bacteria when the tested medium was adjusted for, with the exception for S. aureus which showed similar results to Betadine at 72-hours. CONCLUSION Using commonly encountered topical adjuvants on S. aureus-, S. epidermidis-, and C. acnes-inoculated discs of various implant metals, a significant reduction in biofilm production was observed. BactisureTM, a new FDA-approved topical adjuvant, demonstrated the overall greatest efficacy of the agents studied.