Static vs Articulating Spacers for Two-Stage Revision Total Knee Arthroplasty: Minimum Five-Year Review

BACKGROUND: The gold standard treatment for infected total knee arthroplasty (TKA) is two-stage revision. The first stage involves a temporary antibiotic spacer, which can be static or articulating; it remains unclear which is best. We aimed to compare 5-year outcomes between static and dynamic spacers. METHODS: One hundred and seventy-six patients with infected TKA requiring two-stage revision were enrolled. Patients were organized based on the type of spacer used during the first-stage revision. One hundred and four patients received articulating spacers, and 72 received static spacers. At 5 years, postoperative range of motion (ROM), Short Form 12 (SF-12), Knee Society Score (KSS), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were recorded. Reinfection and revisions were also tracked. RESULTS: Eradication of infection was similar in both groups, with 83.7% in the articulating group and 86.1% in the nonarticulating spacer group (P = .234). Articulating spacers resulted in significantly improved ROM (111 vs 82 degrees, P < .001), SF-12 physical component score (35.2 vs 31.0, P = .01), KSS (145.2 vs 113.7, P < .001), and WOMAC function scores (60.1 vs 51.1, P = .03) as compared to the static spacer group. CONCLUSIONS: Treatment with an articulating spacer as opposed to a static spacer resulted in improved ROM, SF-12 physical component score, KSS, and WOMAC function scores at the final follow-up visit. There was no significant difference in reinfection rates. Patients requiring staged revision for infected TKA may benefit from an articulating spacer.