Efficacy of aerobic exercises for knee osteoarthritis: a network meta analysis of randomized clinical trials

BACKGROUND: Previous research has demonstrated the therapeutic potential of aerobic exercise in alleviating symptoms of knee osteoarthritis (KOA). Nevertheless, comparative evidence regarding the relative effectiveness of different exercise modalities remains inconclusive, and the optimal exercise protocol continues to be debated. To address this knowledge gap, we performed a systematic network meta-analysis to compare and rank the clinical efficacy of various aerobic exercise regimens for managing KOA. METHODS: A systematic literature search was conducted across five electronic databases (PubMed, Cochrane Library, Web of Science, Embase, and Scopus) from database inception through June 2024. Eligible studies included randomized controlled trials (RCTs) evaluating aerobic exercise interventions for KOA management. Two investigators independently performed study selection using predefined inclusion criteria, with discrepancies resolved through consensus or third-party adjudication. Data extraction encompassed demographic characteristics, intervention protocols, and outcome measures. Methodological quality was assessed using the Cochrane Risk of Bias Tool 2.0. Statistical analyses were performed using Stata 17.0 (Network Meta-Analysis package) under a frequentist framework, with treatment effects estimated through surface under the cumulative ranking curve (SUCRA) probabilities. RESULTS: The network meta-analysis included 67 randomized controlled trials comprising 4,944 patients with knee osteoarthritis (KOA), assessing 10 aerobic exercise interventions: walking (WK), weight-loss walking (LK), retro walking (RW), cycling (CY), aquatic training (AT), yoga (YG), Tai Chi (TC), Baduanjin (BD), Wuqinxi (WQ), and Pilates (PT). Surface under the cumulative ranking curve (SUCRA) probability analyses yielded the following results: Pilates (PT) demonstrated the highest probability of being optimal for WOMAC pain score (SUCRA = 0.8%), WOMAC stiffness (SUCRA = 15.7%), physical function (SUCRA = 0.0%), and total WOMAC score (SUCRA = 7.8%). Tai Chi (TC) showed the highest likelihood of efficacy for Visual Analog Scale (VAS) outcomes (SUCRA = 17.4%), while weight-loss walking (LK) ranked first for Timed Up and Go (TUG) improvement (SUCRA = 27.1%). The comprehensive efficacy ranking was PT > LK > BD > YG > AT > WK > RW > TC > WQ > CY. CONCLUSION: This study demonstrates that Pilates appears to be the most effective aerobic exercise modality for managing knee osteoarthritis (KOA), particularly in enhancing overall functional outcomes. Tai Chi exhibited the greatest efficacy in reducing pain intensity, as quantified by the Visual Analog Scale (VAS). Based on these findings, Pilates and Tai Chi should be prioritized as primary therapeutic interventions for the majority of KOA patients.