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 a pulsed 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 pulsed radiofrequency method in patients with chronic discogenic LBP diagnosed by discoblock, in terms of 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 with chronic 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 was applied for 15 minutes at a setting 5x5 ms/s and 60 V. Outcome measures included the pain intensity 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 pre-treatment 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 than 2, 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 as medication requirement or psychological effects were not addressed. CONCLUSIONS This intradiscal PRF method with consecutive PRF 5/5/60V, 15 min (with Diskit needle) appears to be a safe, minimally invasive treatment option for patients with chronic discogenic LBP.