Surgical Site Infections in Knee Surgery Patients: A Comprehensive Review

Surgical site infections (SSIs) are a significant concern in orthopedic surgeries, particularly knee surgeries. Investigator Ramyar Farzan, MD, Department of Plastic & Reconstructive Surgery, School of Medicine for Guilan University of Medical Sciences in Rasht, Iran, was the lead author of a team that conducted a systematic review and meta-analysis to illuminate the prevalence of SSIs and identify associated risk factors in knee surgery patients.

SSIs, occurring within 30 days post-surgery (or within 1 year with implanted devices), are prevalent in orthopedic procedures. This review aimed to assess the prevalence and risk factors of SSIs in knee surgery patients, which is crucial for effective prevention and management.

“The elevated incidence of SSI can be attributed to factors such as the expanding range of orthopedic indications, the intricate nature of orthopedic surgeries, and the frequent use of implants in these procedures,” the authors wrote. “The prevalence of SSI in cases can vary significantly, ranging from 1.4% to 41.9%. The occurrence of this complication following orthopedic surgeries poses unique challenges due to the inherent difficulty in treating bone and joint infections. Additionally, there is a substantial long-term risk, with a 10% [to] 20% lifetime likelihood of recurrence.”

The study’s authors sought to answer 2 primary questions: What is the prevalence of SSIs in patients post-knee surgery, and what are the risk factors associated with SSIs in knee surgery patients?

A systematic search of international and Persian electronic databases yielded 7 relevant studies. Data extraction and quality assessment were performed using the Appraisal tool for Cross-Sectional Studies (AXIS tool). Statistical analysis included a random-effects model and subgroup analysis.

The collective prevalence of SSIs in knee surgery patients was 3.0%, with notable variations across the studies reviewed.

As reported in the 7 included studies, the collective prevalence of SSI in patients who underwent knee surgery was 3.0% (95% CI: 1.2% to 7.5%; I2 = 96.612%; p < 0.001). Prevalence by gender varied. According to the authors, “The odds ratio for the prevalence of SSI in men was greater than that in women; however, this difference did not reach statistical significance (OR: 1.254; 95% CI: 0.726 to 2.166; Z = 0.694; p = 0.487).”

The following statistics provide insights into the prevalence of SSI in patients with health conditions or habits. As reported in 6 studies, the combined prevalence of SSI in patients with diabetes mellitus (DM) was 5.1% (95% CI: 1.7% to 14.5%; I² = 79.054%; p < 0.001).

Based on 4 studies, the pooled prevalence of SSI among patients with hypertension was found to be 1.8% (95% CI: 0.7% to 4.5%; I² = 63.996%; p = 0.040). Additionally, 6 studies indicated that the collective prevalence of SSI in patients with a history of tobacco use was 4.8% (95% CI: 1.4% to 15.2%; I² = 93.358%; p < 0.001).

SSIs pose significant challenges to patients and health care systems, with long-term implications. While gender disparities and comorbidities like DM contribute to SSI prevalence, the study's results show that tailored interventions are essential for mitigation.

Study limitations included heterogeneity among studies and potential publication bias. The authors wrote, “One significant limitation is the substantial variability observed among the studies included in the analysis. High levels of heterogeneity are often a concern in prevalence meta-analyses. Furthermore, the results of the publication bias assessment suggest that further research is necessary to establish the true prevalence of SSI in patients following knee surgery.”

Future research should focus on prospective cohort studies and randomized controlled trials to refine prevention strategies and understand long-term SSI consequences.

The prevalence of SSIs in knee surgery patients highlights the need for tailored interventions addressing diverse risk factors. Through collaborative efforts, health care providers can reduce the burden of SSIs and improve surgical outcomes for knee surgery patients.