Radiofrequency Denervation and Brain Imaging

The goal of this observational study is to learn about changes in brain and its activity of following radiofrequency denervation treatment for chronic low back pain. The main question it aims to answer are:report the magnitude of the brain changes following radiofrequency treatment for low back pain.identify changes unique to radiofrequency treatmentPatients with nociceptive type low back pain of moderate to severe intensity will be identified to undergo radiofrequency treatment. They will have 3 MRI scans - Baseline, after the diagnostic injections and 3 months after radiofrequency treatment. They will also fill questions relating to their pain, disability and health related quality of life.

Inclusion Criteria:Age 18 years or olderChronic moderate to severe cLBP (defined by average pain intensity of ≥ 4 in the 11 point Numerical Pain rating scale and a minimum duration of 1 year)Identified by clinical team as suitable for RFD pathwayPredominantly nociceptive pain (as defined by PainDetect score ≤12)Stable on current analgesic regimeAble to communicate in EnglishHas the capacity to and agrees to give informed consent for participation in the studyPositive response to a single diagnostic MBB with 1 ml or less of local anaesthetic (bupivacaine 0.5%) at each level. (a positive response is defined as ≥80% pain relief at 3 hours, based on patient reported assessment)Exclusion Criteria:Any patient whose physical condition will preclude them from lying still for the duration of the brain scan.Contraindication to magnetic resonance scanning such as an implantable cardiac device.Women who are, or may be, pregnant. (Pregnant patients do not undergo pain procedures under radiological guidance as per routine clinical care)Significant anxiety and depression (as defined by HADS score ≥ 9)Clinical suspicion that alternative diagnosis is the reason for LBPPresence of chronic primary pain conditions (Fibromyalgia, chronic widespread pain, Complex Regional Pain Syndrome, Chronic Primary Headache, Orofacial pain, Chronic primary visceral pian and Chronic Primary musculoskeletal pain as defined by ICD-11 classification)Presence of thoracic or neck painHistory of previous RF denervationRegular use of two or more dependence forming drugs (opioids, gabapentinoids, Benzodiazepines, tricyclics antidepressants and z-drugs)