A randomized controlled trial of radiofrequency denervation of the ramus communicans nerve for chronic discogenic low back pain.

OBJECTIVE: The objective of this study was to determine the efficacy of percutaneous radiofrequency (RF) thermocoagulation of the ramus communicans nerve in patients suffering from chronic discogenic low back pain.

METHODS: Forty-nine patients who suffered chronic discogenic low back pain at only 1 painful vertebral level, and whose pain continued after undergoing intradiscal electrothermal annuloplasty (IDET), were randomly assigned to 1 of 2 treatment groups. The lesion group (n = 26) received RF thermocoagulation of the ramus communicans nerve. Patients in the control group (n = 23) received an injection of lidocaine without radiofrequency. Visual analog scale (VAS) pain scores, analgesic requirements, SF-36 subscales, and the overall patient satisfaction with the procedure were tabulated.

RESULTS: The average follow-up period was 4 months. The patient-reported VAS pain scores were significantly lower (P < 0.05) in the lesion group. The scores of the RF lesion group improved by a mean increase of 11.3 points (P < 0.05) on the SF-36 bodily pain subscale, and by a mean increase of 12.4 points on the physical function subscale (P < 0.05). In a follow-up analysis within the RF lesion group, VAS pain scores improved by a mean reduction of 3.32 (P = 0.001). The scores improved by a mean increase of 14.5 points (P = 0.005) on the SF-36 bodily pain subscale and 15.2 points(P = 0.002) on the physical function subscale within the RF lesion group. One patient in the lesion group complained of mild lower limb weakness, but he completely recovered at postoperative 15 days without any serious problems.

DISCUSSION: In patients with chronic discogenic low back pain, percutaneous RF denervation of the ramus communicans nerve should be considered as a treatment option.