Bipolar intra-articular radiofrequency thermocoagulation of the thoracic facet joints: a case report of a new technique

Previous methods for denervation of the thoracic facet joints involved ablating the medial branch which is variable in location. This study tests the hypothesis that of bipolar radiofrequency thermocoagulation of the thoracic facet joint capsule may provide a safe and effective method of pain control from pain from thoracic facet origin. The design of the study is prospective nonrandomized trial. After IRB approval, 9 patients were selected to have bipolar RFTC. These patients had localized mid back tenderness with pain on extension and lateral bending with no radicular symptoms. All patients had magnetic resonance imaging showing facet disease, no disc extrusions, and no cord/root compromise. These levels were injected with one cc of a solution containing 9cc of 0.5% marcaine mixed with 40 mg of depomedrol after confirmatory arthrogram. Patients who received at least > 50% relief for 8 hours were enrolled in the study. One month later, two Baylis 20 gauge 10 cm radiofrequency cannulas with a 5 mm active tip was guided by fluoroscopy into the inferior portion of the thoracic facet joint. Each cannula was placed side by side in the inferior aspect of the thoracic facet joint 0.5 cm apart. Motor testing was done at 2.5 volts and 2 Hz with no radicular symptoms noted. Then each site underwent bipolar radiofrequency at 80 degrees for 90 seconds. Main Outcome measures were as follows: Visual Analog Scale (VAS) was measured pre-intervention and 1 month post-intervention, any complications, and changes in amount of pain medication were recorded. Significant 47.6% reduction(p=0.028) in VAS was noted at 1 month. There were no serious complications and 33.3 % of patients noted decrease use of pain medication. Intra-articular bipolar RFTC of the thoracic facet joint may be a technically easier and valid method of treating mid back pain of thoracic facet origin.