CLINICAL-RESPONSE TO ANTIBIOTIC-IMPREGNATED POLYMETHYL METHACRYLATE BEAD IMPLANTATION OF DOGS WITH SEVERE INFECTIONS AFTER LIMB-SPARING ANDALLOGRAFT REPLACEMENT - 18 CASES (1994-1996)

Successful treatment of severe orthopaedic infections in people and an imals has been augmented by the use of antibiotic impregnated polymeth yl methacrylate (PMMA) bead implantation at the site of infection. Hig h local wound concentrations of antimicrobials can be achieved without resulting in toxic levels systemically. Clinical, radiographic and pa thological response was evaluated following PMMA beads impregnated wit h vancomycin and tobramycin implanted in 18 dogs with severe infection s following ''limb sparing'' operation with allograft replacement for osteosarcoma. A variety of aerobic and anaerobic bacterial organisms w ere cultured from the sites of infection and numerous systemic antimic robial drug combinations were used in an attempt to control the infect ions prior to the implantation of the beads. In 12 of 18 (67%) dogs im planted, clinical signs of infection resolved within a median of four weeks post implantation. Three of 12 (25%) had recurrence of signs at a median of 17 weeks post implantation. This was not a randomized, pro spective controlled trial and limitations to the study exist, the most notable being the variability in individual patient treatment. Howeve r, antibiotic impregnated PMMA bead implantation may play a role in th e treatment of severe infections in dogs.