Intra-articular oxygen-ozone therapy in knee osteoarthritis: Results of a 31-week randomized, single-blind study versus intra-articular hyaluronic acid

Abstract

Intra-articular (IA) oxygen-ozone (O2O3) has recently grown as a novel therapeutic option in knee osteoarthritis (KOA) and few studies in literature explored its safety and impact on pain and functional status in these patients. The aim of this study was to assess the effectiveness and safety of IA O2O3 compared to ialuronic acid (HA) in terms of pain, knee function, and health-related quality of life in patients affected by KOA over 31 weeks. In this randomized, single-blind, controlled study patients aged ≥ 60 years affected by KOA have been enrolled and randomly allocated to receive 4 IA knee injections once per week for 4 consecutive weeks of O2O3 or HA (T0–T3) and a follow-up visit 4 weeks after the fourth injection (T4). Patients having a Visual Analogue Scale (VAS) ≥ 4 at 6 months follow-up visit (T5) underwent a second treatment cycle (T5–T8) and a 1-month follow-up visit (T9). All adverse events occurred, VAS, Oxford Knee Questionnaire, 12-Item Short Form Health Survey, and European Quality of Life-5 dimensions scores have been assessed. Forty-six patients (mean aged 70.8 ± 2.4 years) were enrolled and randomly allocated to O2O3 (n = 23) or HA treatment group (n = 23). Nineteen patients reported a VAS ≥ 4 at T5, undergoing a second treatment cycle: 10 in O2O3 group and 9 in HA group. There were no significant differences in adverse events occurrence between the two groups. VAS scores showed a statistically significant reduction (P < 0.013) compared to baseline during both treatment cycles in both groups. At both follow-up visits (T4 and T9) the VAS score was significantly lower in the HA group compared to O2O3 group (P < 0.013). IA O2O3 therapy could be comparable to IA HA in terms of safety profile and effectiveness in reducing pain in patients with KOA, even on a multiple injection cycles and long term follow-up.