Use of a tobramycin-impregnated polymethylmethacrylate pin sleeve for the prevention of pin-tract infection in goats

Objective: To test the hypothesis that antibiotic-laden polymethylmethacryl ate (PMMA) pin sleeves prevent infection around skeletal external fixation pins. Design: An experimental study using an animal model was conducted. Animals: In each of five goats, three four-millimeter half-pins were placed in the left and right iliac crests, for a total of thirty half-pins. The p ins were infected with one milliliter of broth containing 7.6 X 10(5) colon y-forming units per milliliter of Staphylococcus aureus (ATCC 25923). Intervention: The pins in the right iliac crest were treated with the tobra mycin-impregnated pin sleeves, and the pins in the left iliac crest (contro l) were left untreated. Results: The results showed clinical evidence of infection (i.e., looseness and gross pus) and heavy bacterial growth (average 6.8 x 10(10) colony-for ming units per milliliter) for the untreated pins, but no clinical evidence of infection and no bacterial growth at forty-eight hours for the treated pins. Conclusion: The present results indicate that the use of the antibiotic-imp regnated PMMA pin sleeve can prevent the development of pin-tract infection and appears to prevent colonization of the external fixation pins.