A Trial of Cooled Radiofrequency Ablation of Medial Branch Nerves for theTreatment of Lumbar Facet Syndrome

Inclusion Criteria: * Patients with lumbar facet syndrome pain who would undergo treatment by lumbar medial branch radiofrequency ablation. * Low back pain for at least 6 months. * Pain resistant to conventional therapy including NSAIDs, opioids, muscle relaxants, oral steroids, physical therapy or chiropractic care. * Pain diagram suggesting possibility of facet-mediated pain. * Referred pain when present not beyond the knee. * Positive response to at least 1 set of diagnostic intra-articular facet injections or medial branch blocks, defined as \> 75% reduction in pain following diagnostic blocks with local anesthetic (0.5mL of 0.5% bupivacaine OR 0.5 mL of 2% lidocaine). Exclusion Criteria: * Focal neurologic signs or symptoms. * Radiologic evidence of a symptomatic herniated disc or nerve root impingement related to spinal stenosis. * Previous radiofrequency ablation treatment for similar symptoms. * Patient refusal. * Lack of consent. * Active systemic or local infections at the site of proposed needle and electrode placement. * Coagulopathy or other bleeding disorder, current use of anticoagulants or anti-platelet medications. * Allergy to medications being used for injection procedures (contrast dye, local anesthetic, IV sedative). * Inability to read English, communicate with staff, or participate in follow up. * Pregnancy. * Cognitive deficit. * Negative response to diagnostic intra-articular facet injections or medial branch blocks, defined as \< 75% reduction in pain following diagnostic blocks with local anesthetic (0.5mL of 0.5% bupivacaine OR 0.5 mL of 2% lidocaine). * Daily opiate analgesic use more exceeding 3 months prior to study inclusion. * Unstable medical or psychiatric illness.