Therapeutic Potential of Acupuncture in Knee Osteoarthritis: Clinical Efficacy and Mechanistic Insights

Knee osteoarthritis (KOA) is a prevalent degenerative joint disorder that significantly compromises joint function due to the progressive degradation of cartilage and persistent inflammation. Acupuncture is an effective technique that has been employed in Traditional Chinese Medicine to treat KOA. This review aims to summarize 21 randomized controlled trials (RCTs) and mechanistic research to investigate acupuncture's clinical efficacy and biological mechanisms in KOA. The literature was sourced from various databases, including PubMed, CNKI, and Google Scholar. Clinical data revealed that acupuncture monotherapy significantly reduces pain intensity (Visual Analogue Scale reductions: 32-54%) and enhances functional capacity (WOMAC score improvements: 25-40%). Furthermore, the combination of acupuncture with moxibustion or electroacupuncture induced synergistic improvements. Mechanistically, acupuncture modulates KOA pathophysiology by suppressing NF-κB-mediated pro-inflammatory cytokines, inhibiting chondrocyte apoptosis (caspase-3 downregulation) while activating autophagy (LC3-II/Beclin-1 upregulation), rebalancing cartilage metabolism by increasing aggrecan/COL2A1 synthesis and MMP-13 inhibition, as well as by attenuating pain transmission through μ-opioid receptor activation and central descending inhibition. These multimodal interventions position acupuncture as a dual-target treatment, mitigating symptoms while inhibiting structural degradation. However, despite promising evidence, further research is warranted for protocol standardization and long-term outcome validation. This review highlights acupuncture's scientific legitimacy as a non-pharmacological approach for the integrated management of KOA, combining traditional methods with modern mechanistic insights.