title: Hand-mixed and premixed antibiotic-loaded bone cement have similar homogeneity.
abstract: Since low-dose antibiotic-loaded bone cement (ALBC) was approved by the FDA for second-stage reimplantation after infected arthroplasties in 2003, commercially premixed low-dose ALBC has become available in the United States. However, surgeons continue to mix ALBC by hand. We presumed hand-mixed ALBC was not as homogeneous as commercially premixed ALBC. We assessed homogeneity by determining the variation in antibiotic elution by location in a batch, from premixed and hand-mixed formulations of low-dose ALBC. Four hand-mixed methodologies were used: (1) suspension--antibiotic powder in the liquid monomer; (2) no-mix--antibiotic powder added but not mixed with the polymer powder before adding monomer; (3) hand-stirred--antibiotic powder stirred into the polymer powder before the monomer was added; and (4) bowl-mix--antibiotic powder mixed into polymer powder using a commercial mixing bowl before the monomer was added. Antibiotic elution was measured using the Kirby-Bauer bioassay. None of the mixing methods had consistently dissimilar homogeneity of antibiotic distribution from the others. Based upon our data we conclude hand-mixed low-dose ALBC is not less homogeneous than commercially premixed formulations.
authors.affiliation: Arizona State University, Phoenix, AZ, USA.
authors.forename: Alex C
authors.initials: AC
authors.lastname: McLaren
authors.forename: Matt
authors.initials: M
authors.lastname: Nugent
authors.forename: Kostas
authors.initials: K
authors.lastname: Economopoulos
authors.forename: Himanshu
authors.initials: H
authors.lastname: Kaul
authors.forename: Brent L
authors.initials: BL
authors.lastname: Vernon
authors.forename: Ryan
authors.initials: R
authors.lastname: McLemore
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000493:pharmacokinetics; D001178:Arthroplasty; D001843:Bone Cements / Q000737:chemistry*; D003460:Crystallization; D004339:Drug Compounding / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D008422:Materials Testing; D010019:Osteomyelitis / Q000517:prevention & control*; D011108:Polymers; D013535:Suspensions; D014732:Vibration
chemical_list: D000900:Anti-Bacterial Agents; D001843:Bone Cements; D011108:Polymers; D013535:Suspensions