Outcome of prosthetic knee-associated infection: evaluation of 40 consecutive episodes at a single centre

ABSTRACTFew studies have compared the long-term success of different surgical strategies in prosthetic knee-associated infection. Accordingly, a retrospective cohort study was performed of 40 episodes in 35 consecutive patients undergoing revision surgery for prosthetic knee-associated infection at a singlecentre between 1988 and 2003. The median patient age was 70 (44–90) years; the median follow-up period was 28 (2–193) months; 45% of infections were early, 23% were delayed, and 32% were late; and 55% of infections were caused by staphylococci. The probability of survival without prosthesis failure was 92.4% (95% CI, 84.1–100) after 1 year, and 88.7% (95% CI, 78–99.4) after 2 years. Recurrence-free survival was observed in 20 (95%) of 21 patients treated with debridement and retention, in both patients with one-stage exchange, and in 11 (85%) of 13 patients with two-stage exchange. Patients with delayed infection had a worse outcome than those with early or late infection (67% vs. 97%; p < 0.03). Patients with at least partially adequate antimicrobial therapy had a higher success rate than those with inadequate treatment (94% vs. 60%; p 0.069). The outcome was similar for patients with a duration of therapy of 3 to < 6 months, and those with a duration of therapy of ≥ 6 months (91% vs. 87% success). Different surgical procedures had similar success rates, provided that the type of infection, the pathogen, the stability of the implant and the local skin and soft-tissue condition were considered. Adherence to an algorithm defining a rational surgical and antibiotic treatment strategy contributed to a favourable outcome

Challenges in periprosthetic knee-joint infection

The number of knee arthroplasty procedures is growing and projected to further increase. The risk for periprosthetic joint infection (PJI) is estimated to be low (>1%). However, considering the increasing number of total knee arthroplasty, the increasing number of patients with multiple comorbidities, and the lifelong risk for acquiring hematogenous infection, the total number of PJI will further increase. Despite existing treatment concepts for PJI of the knee, there are still questions to solve, such as type of debridement surgery in case of implant retention, the role of a spacer from a microbiological perspective, and the optimal duration of antimicrobial therapy. In this REVIEW, these questions will be analyzed according to the available literature and the experience of the authors. Moreover, we REVIEW the most recent data on infection, risk factors, and microbiology of PJI