Antibiotic-loaded bone cement and risk of infection after knee arthroplasty in high-risk patients

Background: The use of antibiotic-loaded bone cement (ALBC) in primary total knee arthroplasty (TKA) is debated. Some argue that ALBC might only be justified in high-risk patients. This study assessed the effectiveness of ALBC vs. plain bone cement (PBC) in reducing risk of revision for periprosthetic joint infection (PJI) in TKA patients considered to have a high risk of infection.

Methods: Cohort study of primary TKAs in 11 national or regional arthroplasty registries from 2010 to 2020. The 1-year risk of revision for PJI in TKAs with ALBC vs. PBC among patients with high American Society of Anesthesiologists (ASA) classification, body mass index (BMI), and/or diabetes was compared. Cumulative percent revision (1 minus Kaplan-Meier) based on 685,818 TKAs and Cox regression analyses (adjusted Hazard Rate Ratios [aHRRs]) were performed for TKAs with ALBC (reference) vs. PBC restricted to the following high-risk subgroups of patients: (1) ASA ≥3 (n = 335,612 vs. 35,997), (2) BMI ≥35 (n = 278,927 vs. 24,737), (3) ASA ≥3 and BMI ≥35 (n = 99,407 vs. 11,407), (4) diabetes (n = 38,341 vs. 21,838), and (5) ASA ≥3, BMI ≥35, and diabetes (n = 3,347 vs. 4,261). Advanced distributed meta-analyses were performed to combine all aggregate data and assess 1-year risk of revision for PJI.

Results: Each registry reported a 1-year cumulative percent revision of ≤1.6% for PJI following TKAs both for ALBC and PBC in all high-risk subgroups. Similar 1-year risks of revision for PJI were found in TKAs with ALBC (reference) and PBC among patients with ASA ≥3 (aHRR: 1.09; 95% CI, 0.90-1.31); BMI ≥35 (1.06; 0.54-2.12); ASA ≥3 and BMI ≥35 (1.12; 0.83-1.50); diabetes (0.95; 0.74-1.20); and ASA ≥3, BMI ≥35, and diabetes (1.40; 0.86-2.29).

Conclusions and Relevance: Similar 1-year revision risk of PJI was found for TKAs with ALBC vs. PBC in high-risk patients. Confirmation of the efficacy of ALBC in high-risk TKA patients needs to be evaluated in clinical trials.

Level of Evidence: Level III. See Instructions for Authors for a complete description of levels of evidence.