Efficiency of Antibiotic-loaded Polymethylmethacrylate Rods for Treatment of the Implant-related Infections in Rat Spine

Study Design: A study of local treatment of the implant-related infections in animal spine. Objective: This study aims to investigate the efficiency of antibiotic-loaded polymethylmethacrylate rods for treatment of the implant-related infections. Summary of Background Data: Today's implant-related vertebral infections are challenging in spinal surgery. In addition to resolving this problem, systemic antibiotic treatment is necessary to study and develop the effectiveness of locally applied treatment methods. Methods: Twenty-four female white Sprague Dawley rats were randomized in 3 different groups, each consisting of 8 animals. Under general anesthesia, 3mm titanium microscrew was implanted in the thoracic vertebra. All 3 groups were inoculated with the same concentration of Staphylococcus aureus (10 6 colony-forming units/10 mu L). Group 1 was assigned as a control group and received no additional therapy, group 2 was given single intraperitoneal doses of vancomycin, and group 3 was implanted vancomycin buffered acrylic rods. Results: The results were analyzed by Fischer exact test. The comparison between the groups revealed a significantly higher therapeutic effect (P < 0.05) in the local therapy group and in the systematic treatment group compared with the control group. The success of the treatment in the systemic treatment group was statistically not significantly different (P > 0.05) compared with the outcome of the locally treated group. Conclusions: This study shows the success of antibiotic-loaded polymethylmethacrylate rods for the treatment of the spinal implant infections. Further research involving clinical studies is required to increase the efficacy and the clinical applicability of the technique.