Five-year survival and complications of more than 300 articulating high-dose antibiotic spacers in two-stage revision total hip arthroplasties for infection.

Abstract

Two-stage exchange arthroplasty with an antibiotic-eluting cement spacer remains the predominant strategy in the USA for managing chronic periprosthetic joint infection (PJI) following total hip arthroplasty (THA). The aim of this study was to evaluate a commercially available, partially intraoperatively fabricated articulating high-dose antibiotic cement spacer, focusing on survival, complications, and patient-reported outcomes. A total of 298 patients (302 THAs) underwent two-stage exchange arthroplasty for PJI using a specific articulating antibiotic spacer between August 2005 and May 2022. Patients with a previous failed two-stage exchange were excluded, although 121 THAs (302, 40%) had undergone previous PJI-related procedures. The mean age of the patients was 65 years (SD 11), the mean BMI was 32 kg/m² (SD 7), and 116 (38%) were female. Most patients were classified as McPherson host B (158; 52%) and limb grade 2 (165; 55%), and 265 (88%) met the 2011 Musculoskeletal Infection Society criteria. The mean follow-up was six years (2 to 16). . At five years after reimplantation, survival free of reinfection, aseptic rerevision, any rerevision, or any reoperation were 89% (95% CI 85.2 to 93.1), 93% (95% CI 89.3 to 96.1), 86% (95% CI 81.3 to 90.3), and 80% (95% CI 74.7 to 84.9), respectively. Dislocation accounted for most aseptic rerevisions (15/20). McPherson host C (HR 3.7 (95% CI 1.4 to 9.6); p = 0.007) and limb grade 3 (HR 3.3 (95% CI 1.0 to 11.1); p = 0.049) were significantly associated with an increased risk of reinfection. The mean Harris Hip Score at the latest follow-up was 76 (29 to 100). A total of 17 patients underwent revision or removal of a spacer for concerns about persistent infection and two for dislocation of the spacer. Eight patients underwent a non-rerevision reoperation during the spacer interval for wound drainage (n = 5), dislocation of the spacer (n = 2), and perispacer fracture (n = 1). A total of 26 spacer-related complications were treated nonoperatively (15 perispacer fractures, 11 dislocations). Dislocation of the spacer was strongly associated with dislocation after reimplantation (HR 6.2 (95% CI 2.3 to 16.9); p < 0.001). This commercially available, partially intraoperatively fabricated articulating spacer showed excellent reinfection-free five-year survival (89%). Spacer-related fracture and dislocation each occurred in 5% of patients. Dislocation of the spacer significantly increased the risk of dislocation following reimplantation, supporting the use of higher-stability bearings in these high-risk patients.