TISSUE DISTRIBUTION OF ANTIBIOTICS IN THE INVERTEBRAL DISC

Study Design. This study analyzed the distribution of antibiotics with in the intervertebral disc of rabbits. Specimens were tested with spec ific antibodies against antibiotics using an immunofluorescent techniq ue. Objectives. The results were correlated to provide a rationale for perioperative prophylaxis of infection. Summary of Background Data. S everal groups of investigators and the recent data from our laboratory showed quantitative changes in penetration of antibiotics into interv ertebral disc. No previous study has assessed antibiotic distribution in anulus fibrosus and nucleus pulposus. Methods. Discs were obtained from rabbits after intravenous injection of penicillin or gentamicin. Antibiotics were localized in tissue sections using specific antibodie s with a immunofluorescent method. Results. Penicillin (negatively cha rged) and gentamicin (positively charged) penetrated the neutrally cha rged anulus fibrosus, but penicillin had less ability than gentamicin to penetrate into the negatively charged nucleus pulposus.Conclusion. Our data suggest that penetration and distribution of antibiotics into avascular intervertebral disc is significantly influenced by the char ge of antibiotics.