Direct versus conventional sonication for the diagnosis of joint infection: A comparative study

Periprosthetic joint infection (PJI) remains a major cause of revision arthroplasty, and accurate diagnostic methods are essential. In this comparative study of 196 revision cases (94 direct vs. 102 conventional sonication), 116 (59.2%) met criteria for PJI. Direct sonication achieved higher sensitivity (86.2%, 95% CI 78.3-92.0) compared with conventional sonication (70.7%, 95% CI 60.4-79.5; p < 0.01), while specificity was comparable (90.3% vs. 94.4%). Importantly, the time-to-positivity (TTP) was significantly shorter with direct sonication (median 2.1 days vs. 3.0 days; p = 0.002), particularly for Gram-positive organisms. These findings demonstrate that direct sonication enhances diagnostic yield, accelerates pathogen recovery, and supports its integration into standardized PJI diagnostic pathways for earlier targeted therapy.