Intradiscal Pulsed Radiofrequency for Chronic Lumbar Discogenic Low Back Pain: A One Year Prospective Outcome Study Using Discoblock for Diagnosis

Background: Discogenic pain is an important cause of low back pain (LBP). We have developed apulsed radiofrequency (PRF) technique, using Diskit II® needles (NeuroTherm, Middleton, MA, USA)placed centrally in the disk, for applying radiofrequency current in the disc (Intradiscal PRF method).Objective: The purpose of this study was to investigate the effect of this intradiscal pulsedradiofrequency method in patients with chronic discogenic LBP diagnosed by discoblock, in termsof pain relief and reduction of disability.Study Design: Prospective case series clinical outcome study.Methods: The participants consisted of 23 patients with a mean age of 35.3 ± 9.86 years withchronic discogenic LBP that was not responsive to aggressive nonoperative care. A Diskit II needle(15-cm length, 20G needle with a 20-mm active tip) was placed centrally in the disc. PRF wasapplied for 15 minutes at a setting of 5 × 5 ms/s and 60 V. Outcome measures included the painintensity score on a 0-10 numeric rating scale (NRS) and the Roland-Morris Disability Questionnaire(RMDQ) at pre-treatment, one, 3, 6, and 12 months post-treatment.Results: The mean pain severity scores (NRS) improved significantly from 7.47 ± 0.85 pretreatment to 3.13 ± 2.58 at the 12 month follow-up (P < 0.01). The RMDQ showed significant (P< 0.01) improvement from 11.4 ± 1.57 pre-treatment to 2.90 ± 2.97 at the 12 month follow-up (P< 0.01). Nineteen of 23 (82.6%) of the patients demonstrated NRS improvements of greater than2, and 15 of 23 (65.2%) had > 50% pain reduction, 12 months after treatment.Limitations: The number of patients was relatively low and secondary outcomes such asmedication requirement or psychological effects were not addressed.Conclusions: This intradiscal PRF method with consecutive PRF 5/5/60V, 15 min (with Diskitneedle) appears to be a safe, minimally invasive treatment option for patients with chronicdiscogenic LBP.Key words: Pulsed radiofrequency, discogenic pain, intradiscal procedures, chronic low backpain, Roland-Morris Disability Questionnaire