title: Contrasting effects of physical wear on elution of two antibiotics from orthopedic cement.
abstract: The use of antibiotics as a supplement to bone cement for the purposes of providing a local release of antibiotics is common practice in arthroplasty surgery and the kinetics of elution of the antibiotics in such systems have been investigated previously. However, in these previous studies no account was taken of the potential effects that wear may have on the elution kinetics of the antibiotic. Here, we have modified an existing wear testing rig to allow the simultaneous study of the elution kinetics of bone cement samples containing antibiotics being subjected to immersion only and immersion and conjoint wear. The results show contrasting effects with two commonly used antibiotics. Bone cement containing daptomycin showed no substantial change in antibiotic elution due to wear, while cement containing gentamicin (the most commonly used antibiotic in this application) in contrast demonstrated a substantial reduction in the rate of antibiotic elution when wear was applied. Scanning electron microscopy revealed a possible explanation for these diverse results, due to wear-induced "sealing" of the surface in conjunction with the crystal morphology of the antibiotic.
authors.affiliation: Materials and Engineering Research Institute, Sheffield Hallam University, Sheffield, United Kingdom.
authors.forename: S
authors.initials: S
authors.lastname: Dodds
authors.forename: T J
authors.initials: TJ
authors.lastname: Smith
authors.forename: R
authors.initials: R
authors.lastname: Akid
authors.forename: J
authors.initials: J
authors.lastname: Stephenson
authors.forename: T
authors.initials: T
authors.lastname: Nichol
authors.forename: R D
authors.initials: RD
authors.lastname: Banerjee
authors.forename: I
authors.initials: I
authors.lastname: Stockley
authors.forename: R
authors.initials: R
authors.lastname: Townsend
mesh_terms: D000085:Acetates; D000900:Anti-Bacterial Agents / Q000737:chemistry*; D001178:Arthroplasty; D032701:Biomimetics; D001843:Bone Cements / Q000737:chemistry*; D002021:Buffers; D003460:Crystallization; D017576:Daptomycin / Q000737:chemistry*; D004058:Diffusion; D005839:Gentamicins / Q000737:chemistry*; D006801:Humans; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D014640:Vancomycin / Q000737:chemistry*
chemical_list: D000085:Acetates; D000900:Anti-Bacterial Agents; D001843:Bone Cements; D002021:Buffers; D005839:Gentamicins; D014640:Vancomycin; D017576:Daptomycin; C018824:ammonium acetate