Dose-Response Effect of Intra-Articular Ozone in Knee Osteoarthritis

The goal of this clinical trial is to evaluate the clinical efficacy of different doses of intra-articular ozone injections combined with exercise in patients aged 40-75 diagnosed with Grade 2-3 knee osteoarthritis. The main questions it aims to answer are: * Which intra-articular ozone doses (10 µg/mL, 15 µg/mL, or 20 µg/mL) is most effective in improving pain and physical function in knee osteoarthritis? * Do combined ozone and exercise therapies provide superior clinical outcomes compared to exercise therapy alone? Researchers will compare four groups (Ozone 10 µg/mL + Exercise, Ozone 15 µg/mL + Exercise, Ozone 20 µg/mL + Exercise and Exercise Alone) to see the dose-dependent effects of ozone therapy. Participants will: * Complete a structured home exercise program for the duration of the study. * Receive 3 sessions of intra-articular ozone injections (for patients allocated to the ozone groups). * Participate follow-up visits for clinical and functional assessments at baseline (before the procedure), immediately after the 3rd injection session, at 1 month after the last ozone injection, and at 3 months after the last ozone injection.