How good are surgeons at disclosing periprosthetic joint infection at the time of revision, based on pre- and intra-operative assessment? A study on 16,922 primary total hip arthroplasties reported to the Norwegian Arthroplasty Register

Abstract

Background and purpose: Revision due to infection, as reported to the Norwegian Arthroplasty Register (NAR), is a surrogate endpoint to periprosthetic joint infection (PJI). We aimed to find the accuracy of the reported causes of revision after primary total hip arthroplasty (THA) compared with PJI to see how good surgeons were at disclosing infection, based on pre- and intraoperative assessment.Patients and methods: We investigated the reasons for revision potentially caused by PJI following primary THA: infection, aseptic loosening, prolonged wound drainage, and pain only, reported to the NAR from surgeons in the region of Western Norway during the period 2010–2020. The electronic patient charts were investigated for information on clinical assessment, treatment, biochemistry, and microbiological findings. PJI was defined in accordance with the Musculoskeletal Infection Society (MSIS) definition. Sensitivity, specificity, and accuracy were calculated.Results: 363 revisions in the NAR were eligible for analyses. Causes of revision were (reported/validated): infection (153/177), aseptic loosening (139/133), prolonged wound drainage (37/13), and pain only (34/40). The sensitivity for reported revision due to infection compared with PJI was 80%, specificity was 94%, and accuracy—the surgeons’ ability to disclose PJI or non-septic revision at time of revision—was 87%. The accuracy for the specific revision causes was highest for revision due to aseptic loosening (95%) and pain only (95%), and lowest for revision due to prolonged wound drainage (86%).Conclusion: The accuracy of surgeon-reported revisions due to infection as representing PJI was 87% in the NAR. Our study shows the importance of systematic correction of the reported cause of revision in arthroplasty registers, after results from adequately taken bacterial samples.

Enhancing the data capture of periprosthetic joint infections in the Danish Knee Arthroplasty Registry: validity assessment and incidence estimation

“…In the Norwegian Arthroplasty Registry, the accuracy of surgeon-reported revision cause in cases due to PJI after THA was 87% [ 30 ], emphasizing the importance of systematic correction of the reported revision cause, when results from biopsies taken during revision surgery are known. In the present study, 21% of missed PJI cases were erroneously registered under other causes in the DKR.…”

“…As surgeons report to the DKR immediately after TKA surgery, when microbiology results are unknown, we hypothesized that misclassification of revision cause would be a major problem. Such misclassification is widely thought to be a contributing reason for the underreporting of revision due to PJI in hip arthroplasty registries [ 30 , 35 ]. However, our results showed that non-reporting was a larger problem than misclassification.…”

Periprosthetic Joint Infection After Total Knee Arthroplasty With or Without Antibiotic Bone Cement

“…A recent register study on revision hip arthroplasty found high accuracy (87%) of surgeon-reported revisions for PJI. 69 Third, the inherent nature of registry data collection may rely on time of surgery, resulting in some inaccuracies in stated causes for revision. For example, revisions attributed to aseptic loosening may ultimately be driven by low-grade infection; thus, registries are likely to underreport infection as a cause of revision.…”