Antibiotic-impregnated Polymethylmethacrylate Beads Research Articles

The use of antibiotic-impregnated polymethylmethacrylate beads to prevent the evolution of localized infection.

The effect of antibiotic bead chains on the evolution of infection cannot be studied entirely in man due to the ethical problems of obtaining valid controls. Therefore, a model of musculoskeletal injury was devised in rabbits by making a paraspinal wound, fracturing a spinous process, and contaminating the wound with 1 x 10(4) colony-forming units/ml of Staphylococcus aureus. These contaminated wounds were treated with tobramycin-containing polymethylmethacrylate (PMMA) beads. Control rabbits were either treated with PMMA beads that did not contain antibiotic, treated with IM tobramycin, or left untreated. At 5 days, six of eight animals treated with antibiotic-impregnated beads had no recoverable organisms. Six of eight rabbits receiving IM tobramycin had wound infections, and five of five in whom non-antibiotic-containing beads had been implanted had significant wound infections, with one of the five dying of sepsis on the 3rd day of the experiment. The clinical course of infected controls was the same as the course of those animals receiving IM antibiotics and the same as those in whom beads without antibiotics were implanted. That is, the rabbits had grossly infected wounds and the organisms recovered were of the same type as those implanted. This research shows a highly statistically significant effect of tobramycin-containing antibiotic beads in retarding the evolution of an experimental Staphylococcus infection in rabbits.

In Vitro and In Vivo Evaluation of Antibiotic Diffusion From Antibiotic-Impregnated Polymethylmethacrylate Beads

The elution of antibiotics from antibiotic-impregnated polymethylmethacrylate (PMMA) beads was measured in mongrel dogs. The antibiotics, used in mixture with Simplex cement, included cefazolin (Ancef; 4.5 g/40 g cement powder), ciprofloxacin (Cipro; 6 g/40 g powder), clindamycin (Cleocin; 6 g/40 g powder), ticarcillin (Ticar; 12 g/40 g powder), tobramycin (Nebcin; 9.8 g/40 g powder), and vancomycin (Vancocin; 4 g/40 g powder). After a pneumatic drill was used to dredge a trough in the tibia, five beads were implanted. During the next 28 days, seroma samples and serum samples were taken for antibiotic measurements. On Day 28, the dogs were killed, beads removed, and the seroma, serum, bone, and granulation tissue sampled. The results of the study showed that clindamycin, vancomycin, and tobramycin exhibited good elution characteristics and had consistently high levels in bone and granulation tissue.

Failure of bipolar hip arthroplasty secondary to retained antibiotic-impregnated polymethylmethacrylate beads. A case report.

Failure of bipolar hip arthroplasty secondary to retained antibiotic-impregnated polymethylmethacrylate beads. A case report.

Noncommercial Fabrication of Antibiotic-impregnated Polymethylmethacrylate Beads

Antibiotic-impregnated polymethylmethacrylate (PMMA) beads were fabricated by means of injections in specially designed molds to produce small and large beads. In vitro concentrates from these beads for 30 days were found to release tobramycin in an exponential function.