Antibiotic Impregnated Acrylic Bone Cements: A Comparative Study of the Mechanical Properties

This study describes a series of mechanical tests to determine the correlations between the strength properties of acrylic bone cement with anti biotic additives and the amount of antibiotic released from the cement. Mechanical test specimens were fabricated from Zimmer LVC and Surgical Simplex RO cements with 2.5 and 5.0 weight percent gentamicin sulfate addi tions. The compressive and tensile strength, as well as the fracture toughness, of control (non-antibiotic) and antibiotic cement specimens were determined. These results were correlated with immunoassay results of the amount of anti biotic released from the samples. Dramatic decreases in strength of the anti biotic cement during the first week correlated with an exponential decrease of released antibiotic over the same time period.