The Effectiveness of a Herbal Supplement in Osteoarthritis.

This study aims to evaluate the effectiveness and safety of a combined herbal supplement containing Boswellia serrata, Curcuma longa, and Vitis vinifera in adults with clinically diagnosed knee or hip osteoarthritis. The primary objective is to determine whether the supplement improves osteoarthritis-related symptoms. The supplement will be compared with a placebo. Participants will: * take the supplement and placebo for 4 weeks each, one at a time; * complete validated questionnaires (6 times online) * perform three performance-based physical tests (6 times online) * provide a urine sample