The optimal impregnation of
antibiotic-loaded
bone cement in the treatment of periprosthetic hip and knee joint
infection is unknown. It is also unclear, whether a suboptimal impregnation might be associated with a higher persistence of
infection. A total of 93 patients (44 knee, 49 hip) were retrospectively evaluated, and the most common organism was a methicillin-resistant Staphylococcus epidermidis, followed by
methicillin-susceptible Staphylococcus aureus. Of all the organisms, 37.1% were resistant against
gentamicin and 54.2% against
clindamycin. All organisms were susceptible against
vancomycin. In 41 cases,
gentamicin-loaded beads were inserted and in 52 cases, spacers: (2 loaded only with
gentamicin, 18 with
gentamicin +
vancomycin, 19 with
gentamicin +
clindamycin, and 13 with
gentamicin +
vancomycin +
clindamycin). The analysis of each
antibiotic impregnation showed that complete susceptibility was present in 38.7% of the cases and partial susceptibility in 28%. In the remaining 33.3%, no precise statement can be made because either there was a culture-negative
infection or the
antibiotic(s) were not tested against the specific organism. At a mean follow-up of 27.9 months, treatment failure was observed in 6.7% of the cases. Independent of which
antibiotic impregnation was used, when the organism was susceptible against the locally inserted
antibiotics or not tested,
reinfection or persistence of
infection was observed in the great majority of cases. Future studies about the investigation of the optimal impregnation of
antibiotic-loaded
bone cement are welcome.