Abstract
Introduction
Periprosthetic joinTt infection (PJI) remains an uncommon, yet devastating complication of total hip arthroplasty (THA) and total knee arthroplasty (TKA). Debridement with antibiotics and implant retention (DAIR) provides an alternative to staged revision. Chronic infection is considered to be a contraindication to DAIR, however, outcomes stratified by chronicity have not been documented.
Methods
We performed a retrospective review of all DAIR cases performed at our institution between 2008–2015. Timeframe to treatment was categorized as acute (< 6 weeks since surgery), chronic (>6 weeks since surgery) or acute hematogenous (previously well-functioning prosthesis). Treatment failure was defined as reoperation during the first 90-days following DAIR. Univariate analysis (Mann-Whitney U and Chi-square; p<0.05) and generalized estimating equations (GEE) were used with multiple comparison adjustment by Tukey-Kramer method (α = 0.05).
Results
282 patients underwent DAIR; 52.8% female; 37.6% THA; 62.4% TKR; mean age: 66.6 (+/−12); mean BMI: 30.3 (+/−7). There were 68 acute (24.1%) patients, 64 (22.7%) chronic and 150 (53.2%) acute hematogenous patients. There was no difference in failure rate between THA and TKA (p=0.09). The data demonstrated that DAIR was more likely to fail in acute (45.6%) compared to chronic (20.3%) or acute hematogenous (25.3%) (OR=4.05; 95 % CI: 2.25 – 7.3, p<0.0001). Staph aureus was the causative organism in 47.1% acute, 18.8% chronic and 28% acute hematogenous. Microbial diagnosis influenced the effect of DAIR results; staph aureus independently increased the failure rate for acute (OR=4.17; 95% CI:1.3–14.3; p=0.02) and chronic (OR=5.89; 95%CI: 1.6–20.0; p=0.01) but not acute hematogenous (OR=1.96; 95% CI: 0.88–4.38; p=0.096).
Discussion
90-day failure of DAIR was higher in the acute compared to chronic or acute hematogenous infection groups. Infection with staph aureus conferred a higher risk of failure for acute and chronic but not for acute hematogenous. DAIR may be more efficacious in chronic PJI than previously considered, particularly for non-staph aureus cases.
