Retrospective Study from a Single Center to Identify Risk Factors Associated with Reinfection in Patients Undergoing 2-Stage Revision Surgery for Periprosthetic Joint Infection

BACKGROUND: This study identified risk factors associated with reinfection and created a scoring system designed for patients with periprosthetic joint infection (PJI) who have undergone prosthetic resection and spacer implantation. MATERIAL/METHODS: Patients who underwent 2-stage revision for PJI from January 2010 to December 2017 were retrospectively analyzed in this study. Patients were divided into 2 groups: infection recurrence and infection cure. Demographic and clinical information, laboratory test results, and radiological images that were potentially associated with infection were obtained and analyzed. RESULTS: Seven independent risk (protective) factors for infection recurrence in patients with PJI who underwent 2-stage hip revision surgery were identified: C-reactive protein level, type of bacterial infection, age, immunosuppression, albumin/globulin ratio, glucose level, and magnetic resonance imaging findings. Finally, a weighted scoring system of 100-mark system was established and the area under the curve was 0.965 (95% confidential interval=0.947–0.983). The predictive scores for low risk (≤30%), moderate risk (31–69%), and high risk (≥70%) of infection recurrence were ≤45, 46–77, and ≥78, respectively. CONCLUSIONS: For patients with PJI who had already undergone joint resection and spacer implantation, this newly established scoring system might help determine the accurate risk of infection recurrence after a definitive new prosthesis implantation. Patients with scores greater than 78 points would be considered very likely to have an infection recurrence. Therefore, the second-stage revision surgery should be changed to an additional anti-infection treatment or a debridement surgery instead of a definitive prosthesis implantation surgery.