25dkou306 10.3205/25dkou306 urn:nbn:de:0183-25dkou3064 Meeting Abstract Rastegar Adib Rastegar Adib Fatemeh F

Experimental Trauma Surgery, Faculty of Medicine, Justus Liebig University of Giessen, Gießen, Deutschland

author Stötzel Stötzel Sabine S

Experimental Trauma Surgery, Faculty of Medicine, Justus Liebig University of Giessen, Gießen, Deutschland

author Abu Mraheil Abu Mraheil Mobarak M

German Centre for Infection Giessen-Marburg-Langen, Institute of Medical Microbiology, Justus Liebig University, Giessen, Deutschland

author Heiß Heiß Christian C

Experimental Trauma Surgery, Faculty of Medicine, Justus Liebig University of Giessen, Gießen, Deutschland

author El Khassawna El Khassawna Thaqif T

Experimental Trauma Surgery, Faculty of Medicine, Justus Liebig University of Giessen, Gießen, Deutschland

author German Medical Science GMS Publishing House

Düsseldorf

610 20251031 engl This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 License. Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung). M0634 306 Deutsche Gesellschaft für Orthopädie und Unfallchirurgie Deutsche Gesellschaft für Orthopädie und Orthopädische Chirurgie Deutsche Gesellschaft für Unfallchirurgie Berufsverband für Orthopädie und Unfallchirurgie Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2025) Grundlagenforschung | Infekt & Diagnostik 2 Berlin 20251028 20251031 AB45-4503 TextObjectives and questions: Bone infections, including osteomyelitis and post-surgical infections, remain a major challenge in orthopedic and trauma surgery, often leading to implant failure, chronic inflammation, and compromised bone healing. Conventional treatment strategies, including systemic antibiotics and surgical debridement, are often ineffective due to high recurrence rates and rising antibiotic resistance. Therefore, localized, sustained-release alternatives are necessary to enhance treatment outcomes.This study aims to evaluate the antimicrobial efficacy, biocompatibility, osteogenic potential, and injectability of a newly formulated bone paste designed to prevent bacterial colonization, eliminate infections, and support bone regeneration in infected bone defects.Materials and Methods: The past containing Calcium Hydroxide (Ca(OH)₂), Polyvinylpyrrolidone (PVP), and Collagen, underwent a comprehensive in vitro study was conducted to assess the biological, antimicrobial, and rheological properties of the bone paste. Cell viability, proliferation, and osteogenic differentiation were analyzed using MSC cultures, while flowability and injectability tests were performed under various storage conditions to ensure handling feasibility. Furthermore, Agar diffusion assays evaluated antibacterial activity against Escherichia coli and Staphylococcus aureus, among others, while co-culture models of bacteria and mesenchymal stem cells (MSCs) assessed the paste’s ability to simultaneously suppress bacterial growth while supporting MSC proliferation.Results: The antimicrobial bone paste demonstrated potent antibacterial effects, with inhibition zones of 1.32 ± 0.15 cm for E. coli and 1.41 ± 0.19 cm for S. aureus, indicating broad-spectrum efficacy. Co-culture experiments confirmed that the paste significantly reduced bacterial growth (>80%) while improving MSC proliferation by 27% compared to controls. Cell viability assays showed 92.5% ± 3.1% survival, corresponding to 1.3 million viable MSCs/mL, with osteogenic markers (Runx2, ALP) up-regulated by 1.5–2.2 fold, suggesting a pro-osteogenic microenvironment. Flowability and injectability tests confirmed that the paste retained its homogeneous consistency and optimal viscosity, maintaining stable injectability (1.8 ± 0.2 N) for at least 21 days, ensuring ease of clinical application. The paste also showed a controlled degradation rate, maintaining structural integrity for up to four weeks in simulated physiological conditions.Discussion and conclusion: The injectable antimicrobial bone paste demonstrated strong antibacterial activity, excellent biocompatibility, and sustained injectability in vitro. Its ability to suppress bacterial growth while promoting osteogenesis underscores its potential as a next-generation treatment for bone infections. Ongoing pilot in vivo studies will further assess its efficacy in infection clearance and bone regeneration, paving the way for future clinical translation possibilities. 0 0 0 0