In Vitro Elution Characteristics of Commercially and Noncommercially Prepared Antibiotic PMMA Beads

Abstract

The successful treatment of osteomyelitis with commercially prepared gentamicin—polymethylmethacrylate (PMMA) (Septopal) beads and surgical debridement has led to the use of this technique in the United States. However, commercially prepared gentamicin—PMMA beads are not currently available to orthopedic surgeons in the United States. Therefore, these surgeons commonly manufacture their own antibiotic-containing cement beads in the operating room at the time of surgery. There is little data that compare the antibiotic elution characteristics of such preparations to commercially prepared gentamicin—PMMA beads. This study compares the measured amount of antibiotic elution of either gentamicin or tobramycin from laboratory manufactured Zimmer, Simplex, or Palacos beads to commercially prepared gentamicin—PMMA (Septopal) beads. During a 30-day study period, commercially prepared gentamicin—PMMA beads eluted more total antibiotic and maintain higher concentrations than did antibiotic acrylic composites manufactured in the authors' laboratory.