Abstract

This study was designed to determine the antibacterial activity of fucidic acid or cefazoline in cancellous bone obtained from patients undergoing total knee replacement. Thirty samples of cancellous bone were obtained from patients undergoing total joint arthroplasty for primary osteoarthritis of knee joints. The prophylactic antibiotics were infused to the subjects an hour before the operation. In the first group (15 samples) fucidic acid (500 mg intravenous) was used as a prophylactic antibiotics and 1^st generation of cephalosporin were used in the second group (15 samples) as the prophylaxis. Same strains of Staphyloccocus aureus were used to assess the antibiotic activity using the disc diffusion technique after 1, 3, 7, 10, 14, 18, 21 and 28 days. The antibiotic efficacy was defined as an inhibition zone diameter of 10 mm. Inhibition zone diameters were significantly higher in fusidic acid than cefazoline specimens on the first, third and 14th day after the incubation (P<0.05). No statistically significant difference was found in the inhibition zone diameter at the seventh, 18^th and 21^st days. Evaluation of inhibition zone diameters showed that samples obtained from the first group (fucidic acid) had a longer duration of antibiotic release than that of second group (cefazolin). Fucidic acid shows a higher release and a longer antibacterial activity when used as a prophylactic antibiotic compared to cefazolin.

Key words: Human cancellous bone, preoperative prophylaxis, fucidic acid, cefazoline.