The impact of extended preoperative examination on the treatment tactics choice before the second stage of revision hip arthroplasty

Abstract

Background. Reinfection and recurrence of periprosthetic infection rates during the second stage of revision hip arthroplasty (RHA) remain quite high. Performing preoperative diagnostic aspiration in patients with the installed hip spacer is a controversial issue. Aims of the study: 1) to compare the diagnostic accuracy, specificity and sensitivity of the used infection markers as a part of preoperative diagnostic protocols in order to exclude reinfection in patients with installed hip spacer before the second stage of RHA; 2) to analyze and compare the microbiological spectrum obtained at the stages of RHA. Methods. Diagnostic accuracy parameters of the used infection markers were assessed in order to exclude reinfection/recurrence in 107 patients with installed hip spacer. All patients were divided into two groups. In Group 1 (prospective), blood tests as well as diagnostic aspiration of synovial fluid were performed within the extended diagnostic protocol. In Group 2 (retrospective), the examination was performed according to the screening preoperative diagnostic protocol including blood tests. The used reference range of inflammatory biomarkers was based on the “small criteria” of ICM 2018. According to the results of the intraoperative microbiological examination of peri-implant tissue samples at the first and second stages of RHA, the analysis of detected microflora was conducted in order to assess probable reinfection/recurrence. Results. According to the results of the intraoperative microbiologic examination during the second stage of RHA, reinfection was detected in 40% of cases: in Group 1 — 9 cases, in Group 2 — 31 case. Synovial fluid was obtained from 85% of cases when preoperative diagnostic aspiration was performed. Synovial fluid could not be obtained in 15% cases (dry joint). Conclusion. Performing preoperative diagnostic aspiration before the second stage of RHA in patients with the installed spacer allowed choosing correct treatment tactics in 9% of cases. The parameters of diagnostic accuracy accounted for 82,6%. In the structure of detected pathogens in case of recurrence and reinfection, the representatives of Gram-positive coagulase-negative flora were the most frequent.