Intra-articular injections of oxygen-ozone versus hyaluronic acid for the treatment of knee osteoarthritis: A randomized controlled trial

Objective: The purpose of this paper was to evaluate the efficacy of intra-articular (AI) injections of Hyaluronic Acid (HA) versus Oxygen-Ozone (O2O3) in relieving pain and reducing disability in patients affected by knee osteoarthritis (KOA). Methods: People with painful KOA for at least three months were randomly allocated to receive three IA injections, once a week, of HA (Group A) vs O2O3 (Group B). They were evaluated at baseline (T0), at 1 (T1), 3 (T2), 6 (T3), and 12 months (T4) after the treatment, using as outcomes: WOMAC pain score, WOMAC LK 3.1, Numeric Rating Scale (NRS), and KOOS. Results: Of the 122 patients assessed for eligibility, 112 participants were enrolled. Both groups A and B showed significant improvements in all outcomes measures from 1 month after the treatment (HA Group: 6.77±2.53 vs 3.66 ±2.57; O2O3 Group: 6.50 ±2.24 vs 3.45 ±2.30). In contrast, at T2 and T3, the HA-treated group showed significant pain and functional improvement compared to O2O3 group. Conclusion: Both HA and O2O3 might be considered safe and potential effective treatments for KOA, due to their antiinflammatory effects. O2O3 seems to have a faster effect; rather, HA showed superior efficacy at 3 months onwards from the end of the treatment.