The Influence of Antibiotic-Loaded Bone Cement Spacer Type on Outcomes of the First Stage of a Revision Total Hip Arthroplasty

<b>Background:</b> There is no consensus on the optimal type of antibiotic-loaded bone cement (ALBC) spacer for ue in the first stage of revision total hip arthroplasty (THA) as a method for treating/managing periprosthetic joint infection (PJI) following THA. The purpose of this study was to determine the influence of ALBC spacer type on a collection of outcome metrics for revision THA (rHA). We hypothesized that infectious complications would be comparable across spacer types, while mechanical complications would be more common with the use of hemiarthroplasty ALBC spacer designs in rHA. <b>Methods:</b> This was a multicenter retrospective review of 144 patients who underwent a planned two-stage revision for THA for PJI between 2011 and 2022. Patients were stratified into three groups: pre-molded articulating hemiarthroplasty ALBC (PHA) spacers, custom articulating hemiarthroplasty ALBC (CHA) spacers, and custom ALBC THA (CTHA) spacers. The types and incidence of complications that arose during the time that the spacer was in situ were obtained. In total, 29 (20.1%) PHA, 11 (7.6%) CHA, and 104 (72.2%) CTHA patients were included. <b>Results:</b> CHA patients were significantly younger (mean age: 54.1 years) than PHA (mean age: 63.9) and CTHA (mean age: 63.9) patients (<i>p</i> = 0.011). The proportion of patients discharged home was significantly higher in the CHA group (81.8%) compared to that in both the CTHA group (64.4%) and the PHA group (34.5%) (<i>p</i> = 0.02). The re-revision rate for hip PJI was higher for CHA (18.2%), followed by PHA (13.8%) and CTHA (5.8%), while hemiarthroplasty spacers had the highest dislocation rate (13.8% in PHA and 18.2% in CHA vs. 3.8% in CTHA, <i>p</i> = 0.055). The vast majority of the outcome metrics did not differ among the three spacer groups, with examples being the incidence of dislocations, the incidence of all types of unplanned procedures for treating/managing re-infection, the time to the second stage in the rHA, and the proportion of spacers that were not removed until the second stage in the rHA. <b>Conclusions:</b> For the vast majority of the outcome metrics determined, the difference among the three study groups was not significant. Thus, the present results suggest that antibiotic-loaded cement spacer type does not influence outcomes when a spacer is used in the first stage of a two-stage protocol for the revision of a THA.