The investigators studied 13 sequential patients of both sexes, between 18 and 70 years old, with persistent
chronic pain (more than six months) in the lumbar region and in the lower limbs related to
failed back surgery syndrome (FBSS).
Pain was classified as neuropathic and non-neuropathic regarding the topography (lumbar and lower limb), based on the DN4 (Douleur Neuropathique 4) questionnaire. The patients received the
ozone gas in the lumbar epidural space via spinal-sacral endoscopy. Clinical evaluation was performed before, immediately after (24 hours), and 1, 3, and 6 months after intervention with visual analog scale and Oswestry Disability Index (ODI).
RESULTS: Overall, the patients had 43.7% reduction of lumbar
pain, 60.9% reduction in leg
pain in six months followed by 44.0% of improvement in ODI. The reduction of
pain and in the disability index was markedly greater in patients with non-neuropathic predominant
pain, 95.2%, 80.6%, and 75.3% improvement in lumbar, leg
pain, and ODI respectively, while neuropathic predominant
pain patients experienced only 12.5%, 42.4%, and 20.9% improvement, also respectively. No neurological or infectious complications were observed acutely or during the follow-up. The present data suggests that epidural
ozone might be a therapeutic option for persistent
low back pain, especially in non-neuropathic predominant
pain patients, but double-blind controlled studies are still required to prove its efficacy.