Introduction and Objectives: Currently it has become popular to use cement impregnated with antibiotics in revisions of septic total knee replacements. However, the use of cement with antibiotics in primary knee arthroplasties continues to be a cause of controversy. However, contrary to American opinion, in some European studies it has been seen that the use of cement with antibiotics decreases the infection rate in primary knee arthroplasties.

Materials and Methods: We hereby present a comparative study of 642 patients that underwent primary total knee replacement (TKR) (Legacy-Zimmer) between 2003 and 200. We divided the patients into 2 groups. One group of 296 patients underwent primary TKR using cement without antibiotic. A second group of 346 patients underwent primary TKR using gentamycin-loaded cement. Mean follow-up was 1 year. Our aim was to find differences in postoperative infection rates during the first year of follow-up

Results: We found no differences in demographic variables, operation time, ischemia time, rate of transfusions, days of hospitalization or medical complications. We saw 10 infections (3.3% infection rate) in group 1. We saw 3 infections (0.09 % infection rate) in group 2. We carried out a comparative statistical analysis and it was significant.

Discussion and Conclusions: Cement impregnated with gentamycin is effective in the prevention of deep infection in the short and medium term in primary total knee replacement.