Complications and Outcomes Associated with Two-Stage Treatment of Periprosthetic Total Knee Infection

Abstract

Background: Chronic periprosthetic joint infection (PJI) has been traditionally treated with two-stage revision. However, single-stage treatment is gaining popularity based on claims of decreased morbidity and mortality. This study sought to evaluate whether two-stage treatment for chronic knee PJI is associated with high morbidity and complication rates compared to existing literature.

Methods: Prospectively collected data on all two-stage knee revisions were retrospectively reviewed (n=97). Modern perioperative optimization protocols were implemented during the interstage and post-reimplantation periods. Surgical complications were quantified for interstage and post-reimplantation periods. Chi-squared tests compared current findings to published data.

Results: Patient sex and age were equivalent, with more current smokers in the present study (P=.001) and more renal failure (P=.002) in the comparison study. Infection complexity in the current study is indicated by 84% late chronic infections in compromised (McPherson) hosts (70%) with 14% polymicrobial infections (unknown for comparison). One percent of cases in the current study did not undergo component reimplantation compared to 8.2% in the comparison study (P=.015). There were no differences in interstage and post-reimplantation septic surgeries (P=.566). Within a year of reimplantation, 9% versus 29% underwent septic reoperation (P=.0002). Using a proposed system from the comparison study penalizing additional operations required to eradicate infection, treatment success rates at minimum one-year follow-up were 56% (current study) and 51% (comparison study) (P=.412). Without these penalties, treatment success in the current study was 64% (unknown for comparison). All-cause mortality rates were the same in both samples (13.4%); however, 9/13 deaths in the current study were unrelated to PJI (unknown for comparison). No patients in the current sample died within the first postoperative year compared to 6.7% in the comparison (P=.024).

Conclusion: Study data suggest morbidity attributed to two-stage treatment for PJI reflects the inherent complexity of this patient group, and not the two-stage treatment itself.