title: Antibacterial efficacy of a new gentamicin-coating for cementless prostheses compared to gentamicin-loaded bone cement.
abstract: Cementless prostheses are increasingly popular but require alternative prophylactic measures than the use of antibiotic-loaded bone cements. Here, we determine the 24-h growth inhibition of gentamicin-releasing coatings from grit-blasted and porous-coated titanium alloys, and compare their antibacterial efficacies and gentamicin release-profiles to those of a commercially available gentamicin-loaded bone cement. Antibacterial efficacy increased with increasing doses of gentamicin in the coating and loading with 1.0 and 0.1 mg gentamicin/cm(2) on both grit-blasted and porous-coated samples yielded comparable efficacy to gentamicin-loaded bone cement. The coating had a higher burst release than bone cement, and also inhibited growth of gentamicin-resistant strains. Antibacterial efficacy of the gentamicin coatings disappeared after 4 days, while gentamicin-loaded bone cement exhibited efficacy over at least 7 days. Shut-down after 4 days of gentamicin-release from coatings is advantageous over the low-dosage tail-release from bone cements, as it minimizing risk of inducing antibiotic-resistant strains. Both gentamicin-loaded cement discs and gentamicin-coated titanium coupons were able to kill gentamicin-sensitive and -resistant bacteria in a simulated prothesis-related interfacial gap. In conclusion, the gentamicin coating provided similar antibacterial properties to those seen by gentamicin-loaded bone cement, implying protection of a prosthesis from being colonized by peri-operatively introduced bacteria in cementless total joint arthroplasty.
authors.affiliation: Department of Biomedical Engineering, University Medical Center Groningen, The Netherlands. d.neut@med.umcg.nl
authors.forename: Daniëlle
authors.initials: D
authors.lastname: Neut
authors.forename: René J B
authors.initials: RJ
authors.lastname: Dijkstra
authors.forename: Jonathan I
authors.initials: JI
authors.lastname: Thompson
authors.forename: Henny C
authors.initials: HC
authors.lastname: van der Mei
authors.forename: Henk J
authors.initials: HJ
authors.lastname: Busscher
mesh_terms: D000497:Alloys; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001843:Bone Cements; D020099:Coated Materials, Biocompatible; D005839:Gentamicins / Q000494:pharmacology*; D006622:Hip Prosthesis / Q000382:microbiology*; D006801:Humans; D066298:In Vitro Techniques; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D016459:Prosthesis-Related Infections / Q000517:prevention & control*; D013203:Staphylococcal Infections / Q000517:prevention & control; D013211:Staphylococcus aureus / Q000187:drug effects / Q000254:growth & development; D014025:Titanium
chemical_list: D000497:Alloys; D000900:Anti-Bacterial Agents; D001843:Bone Cements; D020099:Coated Materials, Biocompatible; D005839:Gentamicins; D014025:Titanium