Mid-Term Effectiveness of Ozone (O2-O3) Compared to Platelet-Rich Plasma (PRP) in the Management of Knee Osteoarthritis: A Randomized Parallel Controlled Trial

Objectives: A randomized parallel controlled trial was designed to compare efficacy of ozone (O 2 -O 3 ) against platelet-rich plasma (PRP) as intra-articular infiltrations in knee osteoarthritis (OA) patients. Methods: Tertiary-level outpatient rehabilitation service. Subjects: Fifty-four patients with knee OA grades 2 a - 4 a according to Kellgren-Lawrencescalewereincludedafterobtaininganinformedconsent. Thetargetsamplesizewas27patientspergroup. Inter-vention: Patientsreceivedfourozone(interventiongroup)orthreeplatelet-richplasma(controlgroup)intra-articularinfiltrations at a one-week interval. Outcome measures: Patients were clinically and functionally evaluated by visual analogue scale (VAS pain) and by Western Ontario and Mac Master index for osteoarthritis (WOMAC) at baseline and at two months follow-up. Pain, stiffness, function, and quality of life (QoL) were evaluated outcome variables. Results: Overall,27patientswererandomlyallocatedtotheinterventiongroup(ozone)and27tothecontrolgroup(PRP).Improve-mentinpain,function,andQoLwereobservedinbothgroupswithoutastatisticaldifference(P> 0.05). Stiffnessimprovementwas significant between similar and different treatment groups (P < 0.05). No side-effects were observed in either group. Conclusions: Ozone (O 2 -O 3 ) is as effective as PRP in the management of knee OA. Both interventions improved pain, function, and QoL with no statistical difference between them.