Enhancing Diagnostic Accuracy for Uncertain Periprosthetic Joint Infection: Combining Cultures With Intraoperative Multisite Sonication

Abstract

Background: Accurate diagnosis of periprosthetic joint infection (PJI) remains challenging, particularly in uncertain cases under the International Consensus Meeting (ICM) 2018 criteria. We explored whether combining cultures with intraoperative multisite sonication could improve diagnostic performance, especially in ambiguous cases. We addressed the following questions: (1) Does multisite sonication combined with standard culture reduce diagnostic uncertainty in PJI? (2) Does multisite sonication improve intraoperative culture positivity? and (3) Do preoperative and intraoperative postsonication bacterial profiles differ?

Methods: A total of 375 patients who were undergoing revision surgery were enrolled, including 242 who had confirmed PJI and 133 who had aseptic loosening. There were four diagnostic models established and compared: Model 1 applied the ICM 2018 criteria without histological data. Model 2 followed the standard ICM 2018 diagnostic criteria, which incorporate histological results and preoperative cultures. Model 3 employed the ICM 2018 criteria with nonsonicated, multisite intraoperative cultures. Model 4 also adhered to the ICM 2018 criteria, but utilized intraoperative multisite cultures with sonication. We compared uncertain PJI incidence in specimens with or without intraoperative sonication, analyzed bacterial spectra, performed receiver operating characteristic analyses, and conducted Kaplan-Meier survival curve evaluations.

Results: For uncertain PJI cases, integrating intraoperative multisite sonication with standard cultures considerably reduced the uncertain case rate from 20.2% based on ICM 2018 criteria excluding histology and 13.6% using standard ICM 2018 criteria down to a final rate of 2.9%. With intraoperative sonication, the synovial fluid, tissue, and prosthesis culture positivity rates increased from 68.4, 64.1, and 57.3 to 72.5, 72.5, and 68.9%, respectively. Integrated culture using multiple sites with intraoperative sonication achieved a positive rate of 89.7%.

Conclusions: Combining multisite sonication with cultures improves diagnostic accuracy and reduces uncertainty in uncertain PJI cases. This integrated approach also provides more reliable pathogen identification, supporting more targeted and timely treatment decisions.

Level of evidence: IV.

Keywords: ICM 2018 diagnostic criteria; intraoperative sonication; multiple-site culture; periprosthetic joint infection; uncertain PJI case.