Mechanical characteristics of antibiotic-laden bone cement.
We studied the mechanical characteristics of cement-antibiotic combinations in vitro. Palacos R was tested without antibiotics, with gentamicin alone and with gentamicin plus vancomycin or flucloxacillin. Palacos LV was studied only with gentamicin added. CMW 1 was studied with gentamicin added, with gentamicin plus vancomycin, and with gentamicin plus flucloxacillin. We performed four-point bending tests on beams of cement to establish bending strength and modulus, and compared the values to ISO standards. Density was also assessed. Palacos R was the strongest of the cements (bending strength 80 MPa). Palacos formulations (apart from Palacos LV) had a higher density and bending modulus than CMW 1. Statistical comparison of various cements with plain Palacos R showed lower density in 4 of the mixtures, and lower bending strength and modulus in 6 of the mixtures. Palacos R/gentamicin plus vancomycin and CMW 1/gentamicin plus vancomycin had bending strength slightly above minimum ISO standards, suggesting that the addition of vancomycin during cement mixing may compromise the outcome in revision surgery for sepsis.
Armstrong
Michael S
MS
Avon Orthopaedic Centre, Southmead Hospital, Bristol, UK.
Spencer
Robert F
RF
Cunningham
James L
JL
Gheduzzi
Sabina
S
Miles
Anthony W
AW
Learmonth
Ian D
ID
D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000627:therapeutic use; D001843:Bone Cements / Q000493:pharmacokinetics* / Q000627:therapeutic use; D004347:Drug Interactions; D004359:Drug Therapy, Combination; D005436:Floxacillin / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000627:therapeutic use; D005839:Gentamicins / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000627:therapeutic use; D006801:Humans; D066298:In Vitro Techniques; D008422:Materials Testing; D010406:Penicillins / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000627:therapeutic use; D019904:Polymethyl Methacrylate / Q000493:pharmacokinetics* / Q000627:therapeutic use; D016459:Prosthesis-Related Infections / Q000517:prevention & control*; D013314:Stress, Mechanical; D013718:Tensile Strength; D014640:Vancomycin / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000627:therapeutic use
D000900:Anti-Bacterial Agents; D001843:Bone Cements; D005839:Gentamicins; D010406:Penicillins; D005436:Floxacillin; D014640:Vancomycin; D019904:Polymethyl Methacrylate