The purpose of this study was to evaluate the accuracy of the sonication fluid cultures (SFC) for the diagnosis of prosthetic joint infection and compare it with frozen section and periprosthetic tissue cultures.

108 patients underwent revision or explantation procedure for any reason. Frozen sections of intraoperative specimen were analized and multiple periprosthetic samples (at least 5) were collected and cultured. All explanted prosthesis components were subject to sonication and cultured. All cultures were incubated for 14 days.

PJI was diagnosed in 52 patients (48%). Sonication achieved the highest sensivity with 95% and specificity of 98%. Frozen section showed low sensivity (44%) and specificity (80%) and periprosthetic tissue cultures showed sensivity of 75% and specificity of 98%.

Sonication fluid culture is a cheap, easy, accurate and sensitive diagnostic method and helps to detect about 30% more PJI compared to frozen section and 16% more compared to periprosthetic tissue cultures. It also detect about 25% more pathogens than periprosthetic tissue cultures