Influence of pain-related psychological factors on therapeutic outcomes in patients with chronic low back pain after oxygen-ozone treatment: a case-series.

The aim of the study was to identify the variables related to therapeutic success of intramuscular oxygen-ozone (O2O3) in patients with chronic low back pain (LBP). Twenty-one patients underwent an eight-session intramuscular-paravertebral O2O3 treatment with a weekly frequency. Numeric Rating Score for pain (NRSp), anxiety (NRSa), mood (NRSm), Oswestry Disability Index (ODI) and Physical and Mental Component Summary scores (PCS and MCS) of Short Form 12 (SF-12) were assessed baseline, after the treatment and at six-months follow-up. The ODI and NRSp scores showed significant improvement at the end of the treatment: the improvement in pain was maintained also at 6 months' follow-up. A significant correlation between baseline NRSa and the variation of the NRSp and ODI was observed. There was a correlation between NRSm at baseline and the variation of the ODI. A moderate correlation between MCS-12 at baseline and the variation of the NRSp score was found. Surprisingly, patients with a more compromised psychological well-being due to LBP had better results after oxygen-ozone therapy. Therefore, NRSa, NRSm and MCS-12 scores could be useful predictors of good therapeutic outcome.