Abstract
BACKGROUND: The optimal management of adult native knee septic arthritis remains controversial. While open arthrotomy and arthroscopic lavage are established surgical strategies, repeated joint aspiration has emerged as a less invasive alternative. This network meta-analysis (NMA) aimed to compare the effectiveness and safety of these three interventions. METHODS: A systematic review and NMA were conducted following PRISMA-NMA guidelines (PROSPERO: CRD420251036819). We searched PubMed, Embase, Scopus, Web of Science, and LILACS through April 25, 2025. Eligible studies included randomized controlled trials and non-randomized comparative studies evaluating repeated aspiration, arthroscopic lavage, or open arthrotomy with adjunctive antibiotic therapy in adult native knee septic arthritis. Two reviewers independently screened studies, extracted data, and assessed bias using ROBINS-I or RoB-2. Pairwise meta-analyses and frequentist NMAs estimated odds ratios (ORs) and mean differences (MDs). Heterogeneity and consistency were evaluated using standard metrics. RESULTS: Twenty-five studies involving 21,917 patients met inclusion criteria (24 retrospective cohorts, 1 low-risk RCT). Arthroscopic lavage showed superior clinical success compared to open arthrotomy (OR 2.52, 95 % CI 1.02-6.27) and fewer complications (OR 0.69, 95 % CI 0.49-0.97). NMA found repeated aspiration associated with higher reintervention risk (OR 3.35, 95 % CI 1.10-10.23) compared to arthroscopy. Open arthrotomy was linked to borderline reduced efficacy (OR 0.51, 95 % CI 0.26-1.02) and more complications (OR 1.44, 95 % CI 1.14-1.82). No significant differences were observed for hospital stay or mortality. Arthroscopy ranked highest in treatment hierarchy. CONCLUSION: Arthroscopic lavage appears to offer the best balance of efficacy and safety and may be the reference standard in immunocompetent adults. Repeated aspiration may be appropriate for selected high-risk patients. Open arthrotomy should be reserved for delayed or complex cases. Further RCTs with standardized outcomes are warranted.