A Systematic Review and Meta-Analysis of Surgical Site Infections in Older Adults Undergoing Total Knee Arthroplasty:

Background. Total knee arthroplasty (TKA), effectively improves joint function and quality of life, but carries the risk of surgical site infection (SSI). SSIs most affect older adult patients with comorbidities. Thus, we evaluated the incidence of SSIs following TKA in older adult populations (≥65 years) and explored the association of SSIs with male sex, morbid obesity, and other comorbidities. Methodology. A systematic review and meta-analysis were conducted according to PRISMA guidelines. Data were extracted from prospective and retrospective studies evaluating the incidence and risk factors for SSIs following TKA in older adults aged ≥65 years. Studies were found through MEDLINE/PubMed, Cochrane Library, and other databases up to 31 July 2024. Risk factors included male sex, morbid obesity, type 2 diabetes, rheumatologic disease, peripheral vascular disease, heart failure, and anaemia. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using a random-effects model. Heterogeneity was assessed using the I² statistic. Results. Twenty studies with a total population of 29,20,681 patients were included. The pooled prevalence of SSIs following TKA was estimated at 1.19% (95% CI: 0.84–1.68%). Male sex was associated with a higher SSI risk (OR: 1.79, 95% CI: 1.45–2.21%). Morbid obesity showed the strongest association with SSIs (OR: 1.47, 95% CI: 1.16–1.86%), followed by type 2 diabetes (OR: 1.28, 95% CI: 1.05–1.56%), and rheumatologic disease (OR: 1.72, 95% CI: 1.09–2.69%). Significant heterogeneity was observed across studies (I² >50%). Conclusion. This meta-analysis highlights the burden of SSIs among older adult patients following TKA, particularly male patients and those with comorbidities. These results indicate the need for individualized risk assessment and preventive strategies to optimize surgical outcomes in this population. Future research should focus on developing tailored interventions for this vulnerable population.