The promotional effect of bone wax on experimental Staphylococcus aureus osteomyelitis

The consequences of using surgical bone wax are not well studied. We evaluated the infection-promoting potential of sterile bone wax in a rat model of chronic Staphylococcus aureus osteomyelitis. The addition of bone wax greatly reduced the quantitative bacterial inoculum (log colony-forming units) required to establish chronic osteomyelitis in 50% and 100% of challenged animals. The 50% infection rate was reduced from log 6.9 to 2.6 and the 100% infection rate from 8.2 to 4.4, respectively (p < 0.015, t test for parallelism). Separate experiments were done 10 to 30 minutes after inoculation with only log 6.4 staphylococci. Tibiae of animals that received bone wax yielded more organisms than those that did not (log 2.76 ± 0.68 versus 1.72 ± 0.94, p < 0.01). At 24 hours quantitative colony counts were not significantly different whether animals received wax or not (log 5.02 ± 0.42 versus 4.43 ± 0.65, p > 0.09). These studies suggest that the routine surgical use of bone wax should be reassessed.