Accuracy of joint aspiration for the preoperative diagnosis of infection in total hip arthroplasty.

The aim of this study was to assess the diagnostic accuracy of radiology department-based hip aspiration for the diagnosis of infection after total hip arthroplasty. Patient selection criteria were devised so that only patients with moderate to high risk of infection were selected for hip aspiration. Seventy-three patients are included in this study, all of whom underwent revision hip surgery after aspiration. Culture results of hip aspirates were compared with the intraoperative tissue cultures at the time of revision surgery, which was used as the gold standard for diagnosing infection. Seventeen patients (23%) had infected hip joints at operative culture. The sensitivity and specificity, positive and negative predictive values, and accuracy of the hip aspiration were 0.82 and 0.91, 0.74 and 0.94, and 0.89, respectively. We conclude that hip aspiration carried out in the radiology department is reliable, but appropriate patient selection is important to obtain accurate results.