Complications and outcomes associated with two-stage treatment of periprosthetic total hip infection jacob schmidt, mary ziemba-davis, r. michael meneghini indiana university school of medicine; indiana university health physicians, iu health hip & knee center, saxony hospital; indiana university school of medicine, department of orthopaedic surgery background and hypothesis: periprosthetic joint infection (pji) is treated with implant resection, debridement, and component reimplantation after infection eradication. treatment consists of either a single surgery or two-stage surgery with intravenous antibiotic therapy between stages. we replicated a recent study which concluded two-stage treatment is associated with high morbidity, hypothesizing that complication rates would be similar, but that morbidity is not always conclusively a consequence of two-stage treatment for pji project methods: prospectively documented data on all primary and revision hips undergoing two-stage treatment for pji by a single surgeon were retrospectively reviewed. surgical complications were quantified for the interstage and post-reimplantation periods. chi-squared tests were used to compare current findings to published findings. results: six of seven patient demographics and comorbidities were equivalent in the two studies (p ≥ .278). more complex infections characterized the current study as evidenced by significantly more polymicrobial infections (p < .001). spacer retention rather than component reimplantation did not occur in the current study but characterized 32 patients (16%) in the comparison study (p = .002). there were no differences in the number of additional interstage septic procedures (p = .402) and fewer post-reimplantation septic surgeries in the current study (p = .018). using a proposed system which penalizes additional operations required to eradicate infection, treatment success rates at minimum one year follow-up were 73% and 71%, respectively (p = .856). without these penalties, treatment success in the current study was 93% (equivalent proportion not available for comparison study). all-cause mortality was higher in the current study (18.2% versus 7.6%, p = .044) but only two deaths were related to pji (unknown for comparison study). potential impact: study findings suggest that morbidity attributed to two-stage treatment reflect the inherent complexity of this patient group, and not the two-stage treatment itself