Results of pulsed radiofrequency technique with two laterally placed electrodes in the annulus in patients with chronic lumbar discogenic pain.

Discogenic pain is an important cause of low back pain (LBP). We have developed a pulsed radiofrequency (P-RF) technique, using two electrodes placed bilaterally in the annulus, for applying radiofrequency current in the disc (bi-annular P-RF disc method). The purpose of this study was to investigate the effect of the bi-annular P-RF disc method, using Diskit needles (Neurotherm, Middleton, MA, USA) in patients with discogenic LBP. The subjects were 15 patients with a mean age of 37.3 ± 8.63 years with chronic discogenic lower back pain that was not responsive to aggressive nonoperative care. Two Diskit II needles (15-cm length, 20G needles with a 20-mm active tip) were placed bilaterally in the annulus in the disc. Pulsed radiofrequency was applied for 12 min at a setting of 5 × 50 ms/s and 60 V. The pain intensity scores on a 0-10 numeric rating scale (NRS) and the Roland-Morris Disability Questionnaire (RMDQ) were measured pretreatment, and at 1 week and 1, 3, and 6 months post-treatment. The mean pain severity score (NRS) improved from 7.27 ± 0.58 pretreatment to 2.5 ± 0.94 at the 6-month follow-up (p < 0.01). The RMDQ showed significant (p < 0.01) improvement, from 10.70 ± 2.35 pretreatment to 2.10 ± 1.85 at the 6-month follow up (p < 0.01). The bi-annular P-RF disc method with consecutive P-RF 5/5/60 V, 12-min (with Diskit needle), appears to be a safe, minimally invasive treatment option for patients with chronic discogenic LBP.