Abstract
Antibiotic-Impregnated polymethylmethacrylate (PMMA) beads for treatment of osteomylitis were evaluated for efficiency and safety ; dose and duration were decided for the purpose of clinical use. Control and DKB-Impregnated PMMA beads were made by mixing dideoxykanamicin B (DKB) 0g 0.5g and 1g with 10 g cement powder. In dogs, the beads were implanted into the femoral cavity ; beads were removed at 3 days, 1, 2, 4, 8, 16 and 24 weeks. The serum concentrations, elusionkinetics of removed beads, and tissue concentrations of surrounding beads in 4 tissues were measured ; histological studies were perfomed. The peak serum concentration of 4.31μg/ ml was measured at 3 hours after implantation of 1g beads. By 3 days DKB was no longer demonstrable. Pathological findings were no different in surrounding tissues. With high-dose DKB beads, there were no side effects systemically or locally. Elusionkinetics of removed beads was measured ; 25.50μg/ml 0.5g beads, 515.1μg/ml 1g beads at 24 weeks after implantation. DKB concentrations of surrounding tissues were highest in the scar tissues followed by the muscle, cancellous bone, and cortical bone. DKB concentrations were measured in the scar tissues as evidence of efficiency ; 8.21μg/g in 0.5g beads at 8 weeks, 6.45μg/g in 1g beads at 24 weeks. The best dosage of beads was 1 g mixed with 10 g cement because this dosage showed no side effects and high efficiency. The removal time of the beads was best within 24 weeks for 1g beads. Based on the results of this study, the efficiency and safety of PMMA beads for the treatment of osteomylitis were confirmed by maintaining a high concentration in local bone tissues for a long time by eluting the antibiotics from the beads ; there were no side effects systemically and locally.
