gms | German Medical Science

Fragestellung: The two-stage procedure with an interval of >6 weeks until reimplantation is considered the "gold standard" in the management of periprosthetic joint infections (PJI). Limited data suggest that a shorter interval is at least as successful as longer time intervals in selected patients. Theoretically, early reimplantation can provide several potential advantages, including faster patient mobilization and less muscle atrophy. However, lower cure rates in shorter intervals are of concern. We compared the treatment outcome of hip and knee PJI treated with a short (< 6 weeks) and long interval ( >6 weeks) in eradicating infection.

Methodik: In this prospective study, all consecutive hip and knee PJI cases from 2013 to 2015 treated in our institution were included. Patients were allocated to a short (< 6 weeks) or long ( >6 weeks) prosthesis-free interval, randomly determined by the availability of operating room. A standardized treatment-algorithm including surgical procedures and antimicrobial therapy was applied in all patients. Patients with infections caused by a difficult-to treat-organism (rifampin-resistant staphylococci, enterococci, ciprofloxacin-resistant gram-negative bacteria and fungi), patients with additional revision surgeries during interval because of persistent infection and insufficient soft tissue coverage were excluded. Treatment failure was assessed according to the Delphi-based consensus definition. Logistic regression analysis was performed to assess the risk factors for failure.

Ergebnisse und Schlussfolgerung: Among 132 patients with hip (n=67) and knee (n=65) PJI, 33 cases were treated with a short interval (mean: 26.6 days) and 99 with a long interval (mean: 64.3 days). Eradication of infection was achieved in 32 cases (97%) with a short interval and in 84 cases (85%) with a long interval (p=0.07). The mean patient follow-up was 28 months (range, 12-42 months). The mean total duration of antimicrobial therapy was significantly shorter in the short interval group (90 days) than in long interval group (117 days) (p<0.001), but the duration of antibiofilm active therapy was significantly longer in short interval group due to earlier reimplantation (55 vs. 39 days; p< 0.001). Also treatment failures had a significantly shorter duration of antibiofilm active therapy compared to patients with successful infect eradication (32 vs. 44 days, p=0.037) When controlling for other variables using multivariate analyses, the risk of treatment failure was higher in episodes with higher Charlson comorbidity score and involving knee joint. Usage of modern antibiotic concepts with antibiofilm activity allows a shortening of the prosthesis-free interval in a two-stage exchange arthroplasty without impairing the infect eradication rate and plays a crucial role in optimal outcome in PJI. Early implantation of the prosthesis with longer administration of antibiofilm active therapy may improve the treatment outcome in selected patients.