title: Prophylaxis of infection and effects on osseointegration using a tobramycin-periapatite coating on titanium implants--an experimental study in the rabbit.
abstract: No options are available for local antibiotic delivery from uncemented implants. By loading a porous titanium implant with a biomimetic HA-coating (PeriApatite, PA) with antibiotics, we could obtain adequate local antibiotic concentrations and reduce infection susceptibility. This study investigated the efficacy of a tobramycin-loaded PA-coated titanium foam implant in preventing infection, as well as the effects on osseointegration. In 72 New Zealand White rabbits, an uncoated (Ti), PA-coated (PA), or Tobramycin-PA-coated (PA-tobra) titanium foam rod was implanted intramedullary in the left tibiae after contamination of the implant bed with none (control), 10(3), 10(4) or 10(5) CFU Staphylococcus aureus. PA-tobra implants were loaded with 2.4 mg tobramycin. After 28 days analysis was done by bacteriology, histopathology and histomorphometry. Six percent of the contaminated PA-tobra rabbits were infected, whereas this was 53 and 67% for PA and Ti, respectively (p < 0.001). Quantitative cultures were also significantly lower in the PA-tobra group (p = 0.003). None of the control rabbits were infected. Histopathological and histomorphometrical scores were both better for the PA-tobra group, although only significant compared to Ti. No significant differences were observed between PA and Ti rabbits. We conclude that the application of tobramycin to PA-coated titanium foam implants appears to be an effective local antibiotic strategy for uncemented implants for infection prophylaxis and has a beneficial effect on implant fixation, which will result in improved long-term implant survival.
authors.affiliation: Department of Orthopaedics, University Medical Center Utrecht, Room G05.228, P.O. Box 85500, Heidelberglaan 100, 3484CX Utrecht, The Netherlands. D.J.F.Moojen@umcutrecht.nl
authors.forename: Dirk Jan F
authors.initials: DJ
authors.lastname: Moojen
authors.forename: H Charles
authors.initials: HC
authors.lastname: Vogely
authors.forename: André
authors.initials: A
authors.lastname: Fleer
authors.forename: Peter G J
authors.initials: PG
authors.lastname: Nikkels
authors.forename: Paul A
authors.initials: PA
authors.lastname: Higham
authors.forename: Abraham J
authors.initials: AJ
authors.lastname: Verbout
authors.forename: René M
authors.initials: RM
authors.lastname: Castelein
authors.forename: Wouter J A
authors.initials: WJ
authors.lastname: Dhert
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001031:Apatites; D001858:Bone Nails / Q000382:microbiology; D020099:Coated Materials, Biocompatible; D005260:Female; D016348:Osseointegration / Q000187:drug effects*; D016459:Prosthesis-Related Infections / Q000473:pathology / Q000517:prevention & control*; D011817:Rabbits; D013203:Staphylococcal Infections / Q000473:pathology / Q000517:prevention & control; D013211:Staphylococcus aureus / Q000187:drug effects; D014025:Titanium; D014031:Tobramycin / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D001031:Apatites; D020099:Coated Materials, Biocompatible; D014025:Titanium; D014031:Tobramycin