Intra-articular ozone modulates inflammation, ameliorates pain and rigidity, improves function and has anabolic effect on knee osteoarthritis: A prospective quasi-experimental before-and-after study, 115 patients

Abstract

Purpose: The objective of the present study is to verify for the first time in the literature the symptomatic and modifying disease effect of ozone (O2-O3) through clinical (pain, function and stiffness), biochemical (C-reactive protein [CRP], erythrocyte sedimentation rate [ESR], uric acid) and radiological improvement (minimum medial and lateral joint space) in a series of patients with osteoarthritis of the knee. Methods: A prospective quasi-experimental before-and-after study was performed in 115 patients with knee osteoarthritis Kellgren-Lawrence grade 2 or more. The ozone protocol consisted of 4 sessions (one session / week) of an intra-articular injection of 20 ml of a medical mixture of Oxygen-Ozone (95-5 %) at a concentration of 20 μg / ml. Outcome variables included clinical (pain, stiffness, and function), biochemical (CRP, ESR, uric acid), and radiological variables (minimal femorotibial joint space). Results: Mean age of the patients was 64.81 ± 11.22 years. Female patients accounted for 75.6 % (n = 87), with a female / male ratio of 3 : 1. Biochemical-variables: CRP decreased from 0.42 ± 0.54 mg/dL to 0.31 ± 0.33 mg/dL (p = 0.0142). ESR decreased from 14.52 ± 10.14 mm/h to 13.08 ± 8.78 mm/h (p = 0.0014). Serum uric acid decreased from 5.12 ± 1.22 mg/dL to 5.05 ± 1.24 (p = 0.1307). Clinical variables: Ozone (O2-O3) significantly improved pain, stiffness and function clinical variables (p = 0.0000). Pain measured by VAS was 7.11 ± 1.11 points and decreased significantly to 3.56 ± 1.56 points (p = 0.0000). Before the intervention, WOMAC-pain subscale was 14.3 ± 22.29 points and decreased to 7.13 ± 33.13 points (p = 0.0000), WOMAC-stiffness subscale was 2.73 ± 1.39 points and decreased to 1.16 ± 1.13 points (p = 0.0000), WOMAC-function subscale was 41.66 ± 8, 1 points and improved to 25.29 ± 9.72 points (p = 0.0000). Radiological variables: In 53 patients analyzed radiologically (according to standardized protocol) at one year of follow-up after ozone treatment, the internal compartment increased significantly from 4.12 ± 1.41 mm to 4.4 ± 1.35 mm (p = 0.0008) and the external compartment increased from 6 ± 1.37 to 6.16 ± 1.4 mm (p = 0.0753). Conclusions: Intra articular ozone has demonstrated a symptomatic and disease modifying effect in patients with osteoarthritis of the knee, improving pain, function and stiffness; decreasing markers of inflammation (CRP, ESR and uric acid), and increasing the minimal joint space of the medial and lateral component evidenced radiologically. In this study it has been shown that ozone modulates inflammation, decreases pain and stiffness, improves function and has an anabolic effect in patients with osteoarthritis of the knee. No adverse effect has been observed after intra articular infiltrations of ozone.