Knee Osteoarthritis: Condroprotector Action and Symptomatic Effect of Ozone on Pain, Function, Quality of Life, Minimal Joint Space and Knee Arthroplasty Delay

Abstract

Objectives: To evaluate the effect of Ozone on pain, function, quality of life, minimal joint space and knee arthroplasty delay in a case series of patients with knee osteoarthritis (OA). Methods: Prospective quasi-experimental before-after study on 52 out of 120 patients with knee osteoarthritis (OA) Kellgren-Lawrence (K-L) grade 2 or more, who attended Santa Cristina's University Hospital, from January 2012 to June 2016. The Ozone protocol consisted of four sessions (1 session/week) of an intra-articular infiltration of a medical mixture of oxygen-ozone (95% - 5%) at a 20 µg/mL concentration. Pain and quality of life (QoL) were measured by visual analogical scale (VAS) and western ontario and Mc master universities index for osteoarthritis (WOMAC), and minimal internal/external joint space width were measured by plain posterior-anterior weight-bearing knee radiographies at the beginning / end of treatment. Results: Mean age 70.36 years. Women 80.8% (n = 42), men 19.2% (n = 10). The severity of OA according to Kellgren-Lawrence scale was 3° (n = 36; 69.2%). Pain measured by VAS significantly decreased (P < 0.0001) from 8.1 to 2.5. The WOMAC-pain, WOMAC-stiffness and WOMAC-function subscales decreased significantly (P < 0.0001) from 16.5 to 4.9 points, 3.2 to 2 and 48 to 17.6, respectively. With respect to minimal joint space, the internal compartment measured 4.17 mm and increased significantly to 4.44 mm (P = 0.0003); while the external compartment was 6.02 mm and improved significantly to 6.26 mm (P = 0.0032) after the treatment protocol. After a mean of 10 months follow-up to a maximum of 28 months, none of knee OA patients underwent knee arthroplasty replacement. Conclusions: Ozone treatment is capable of producing pain relief, recovery of function and radiological improvement on minimal joint space in knee OA patients. Based on the results of our study, it is assumed that Ozone could slow/revert OA progression, due to the increase in the minimal internal and external joint space width. Ozone treatment delays the need for total knee arthroplasty.