Development of a Preoperative Risk Calculator for Re-Infection Following Revision Surgery for Periprosthetic Joint Infection

Abstract Introduction A recent systematic review demonstrated re-infection rates following eradication of hip and knee periprosthetic joint infection (PJI) may be as high as 29%. This study aimed to develop a preoperative risk calculator for assessing patient’s individual risk associated with re-infection following treatment of periprosthetic joint infection (PJI) in total joint arthroplasty (TJA). Methods A total of 1081 consecutive patients that underwent revision TJA for PJI were evaluated. 293 patients were diagnosed with TJA re-infection. A total of 56 risk factors, including patient characteristics and surgical variables, were evaluated with multivariate regression analysis. Analysis of the area under the receiver operating characteristics curve (AUC) was performed to evaluate the strength of the predictive model. Results Of the 56 risk factors studied, 19 were found to have a significant effect as risk factor for TJA re-infection. The strongest predictors for TJA re-infection included previous PJI treatment techniques such as irrigation and debridement, the number of previous surgical interventions, medical comorbidities such as obesity, drug abuse, depression and smoking, as well as microbiology including the presence of Enterococcus species. The combined AUC of the risk calculator for periprosthetic hip and knee joint re-infection was 0.75. Discussion The study findings demonstrate that surgical factors, including previous PJI surgical treatment techniques as well as the number of previous surgeries, alongside microbiology including the presence of Enterococcus species have the strongest effect on the risk for periprosthetic THA and TKA joint re-infection, suggesting the limited applicability of the existing risk calculators for the development of PJI following primary TJA in predicting the risk of periprosthetic joint reinfection.