1. 2020;23;E535-E540Intradiscal Pulsed Radiofrequency Application Duration Effect on Lumbar Discogenic Low Back Pain
   Retrospective Study
   Chan Hong Park, MD, PhD, Sang Ho Lee, MD, and Pyng Bok Lee, MD.

BACKGROUND: Discogenic pain is recognized as the most important and most common cause of low back pain (LBP). Intradiscal pulsed radiofrequency (ID-PRF) is used for the treatment of chronic discogenic pain.

OBJECTIVES: We investigated the effects of the duration of percutaneous monopolar ID-PRF application on chronic discogenic LBP.

STUDY DESIGN: Retrospective study.

SETTING: Department of Anesthesiology and Pain Medicine, Neurosurgery at Wooridul Spine Hospital.

METHODS: Forty-five patients were included in this retrospective study. The patients were assigned into 2 groups according to the duration of the PRF procedure they underwent (7-minute group = 17 patients vs. 15-minute group = 28 patients). The main outcome measures tested were pain score, as determined by the Numeric Rating Scale (NRS-11) and the Oswestry Disability Index (ODI), at baseline, at 2-week, and 6-month follow-up visits. Success was defined as a reduction in NRS-11 of 50% or more or an ODI reduction of 40% or more.

RESULTS: The mean posttreatment pain scores at 2 weeks and 6 months were significantly lower (P < 0.05) in both groups, but the differences between the groups were not significant. ODI scores were also significantly lower compared with the baseline, but the differences between the groups were not significant. At the 6-month follow-up, 12 patients (70.6%) in the 7-minute group and 20 patients (71.4%) in the 15-minute group reported more than 50% reduction in the pain score (P = 0.16), and there was no significant difference between the 2 groups in the number of patients with more than 40% reduction in ODI score (P = 0.23).

LIMITATIONS: This study was performed with a small sample size and there was no control group. Additional well-designed and well-controlled studies that include parameters such as the stimulation duration, mode, and intensity of PRF are needed to fully assess the efficiency of ID-PRF.

CONCLUSIONS: ID-PRF was shown to be effective for the treatment of discogenic LBP regardless of duration of ID-PRF application (7 vs. 15 minutes).

KEY WORDS: Discogenic pain, pulsed, radio frequency, duration, pain, reduction