Local treatment of chronic osteomyelitis with surgical debridement and tigecycline-impregnated calcium hydroxyapatite: an experimental study

Abstract

The aim of this study was to determine the efficacy of tigecycline-impregnated hydroxyapatite in the local treatment of chronic osteomyelitis experimentally induced in rat tibias with methicillin-resistant Staphylococcus aureus. Monocortical defects were established in the left tibias of 32 adult Wistar albino rats. Five rats were randomly selected and injected intramedullarly with saline solution (group 1), whereas chronic osteomyelitis was induced in other rats by intramedullary injection of S. aureus. Infected rats were then randomized and divided into 4 groups: group 2, no further treatment; group 3, debridement only; group 4, debridement followed by implantation of calcium hydroxyapatite; and group 5, debridement followed by implantation of tigecycline-impregnated calcium hydroxyapatite. On day 21 after induction, all rats in groups 2-5 showed signs of osteomyelitis. Rats in groups 1 and 2 were killed on day 21 after induction, whereas rats in groups 3, 4, and 5 underwent debridement surgery on day 21 after induction and were killed 21 days after debridement surgery. Tibias were analyzed histopathologically and cultured for S. aureus. Compared with group 2, histopathologic disease severity scores in groups 3, 4, and 5 were 37%, 44%, and 83% lower, respectively. Nontreated infected rats had the highest bacteria count (mean 5 × 10(5) colony-forming units/g bone), and bacterial count was 26%, 29%, and 79% lower in groups 3, 4, and 5, respectively, compared with group 2. Tigecycline-impregnated hydroxyapatite can have a potential in the treatment of chronic osteomyelitis of methicillin-resistant S. aureus origin, which may be considered as a therapeutic alternative by surgeons dealing with osteomyelitis.