Evaluating the efficacy and safety of Curcuma longa, Boswellia serrata, and their mixed formulation in treating knee osteoarthritis: A systematic review and network meta-analysis.

BACKGROUND

Herbal interventions such as Curcuma longa (CL) and Boswellia serrata (BS) have demonstrated efficacy and safety in managing knee osteoarthritis (KOA); however, the effects of their combined formulation, including both direct and indirect outcomes, remain insufficiently explored. We performed systematic review and network meta-analysis for clinical effects of CL, BS, and their mixed formulation in alleviating KOA symptoms.

METHODS

The CENTRAL, PubMed, EMBASE, and EBSCO Open Dissertations, databases and also from Snowballing and citation searching were searched through March 2025. The randomized controlled trials (RCTs) that studied effectiveness of CL or BS in KOA participants using Visual Analog Scale (VAS) and KOA severity by the Western Ontario and McMaster Universities Arthritis Index (WOMAC), and adverse events as the main outcomes, were eligibly included. The Cochrane Risk of Bias a random-effects model, standardized mean differences (SMDs) along with 95 % confidence intervals (CIs) were employed.

RESULTS

In total, 20 RCTs comprising 1633 participants were included. The modified formulations of CL showed a significant reduction in VAS compared to placebo (SMD: -2.82; 95 %CI: -5.30 to -0.33), while the modified formulations of BS demonstrated significant improvement in WOMAC pain, stiffness, and knee function compared to other intervention groups. No significant differences in adverse events were observed among all comparisons.

CONCLUSIONS

BS extract, particularly in modified formulations, improves joint function in patients with mild to moderate KOA, while only the modified formulation of CL demonstrates notable pain-reducing efficacy. The potential benefits of combined CL and BS preparations warrant further investigation.