Effects of producing a radiofrequency lesion adjacent to the dorsal root ganglion in patients with thoracic segmental pain.

Objective: To evaluate the effectiveness of a radiofrequency lesion adjacent to the dorsal root ganglion (RF-DRG) on a consecutive group of patients presenting with chronic thoracic pain.

Design: Retrospective study by a disinterested third party.

Setting: Clinical outcome study.

Patients: Forty-three patients with a minimum of 6 months history of unilateral thoracic segmental pain, unresponsive to conservative therapy were involved.

Interventions: Patients were selected for a radiofrequency lesion adjacent to the dorsal root ganglion after two or more prognostic nerve blocks had been performed under fluoroscopic control. The level which provided the best analgesic response was selected. At this level, a radiofrequency lesion was made at 67 degrees for 60 s immediately adjacent to the dorsal root ganglion.

Outcome Measures: Rating of pain was done on a four-step verbal rating scale.

Results: A radiofrequency lesion adjacent to the dorsal root ganglion provided short-term (8 weeks) relief of pain in 67% and long-term relief (> 36 weeks) of pain in 52% of patients with a limited segmental distribution of pain. If more than two segmental levels were involved, the procedure was found to be less effective.

Conclusions: There was a significantly (p < 0.05) better short-term and long-term pain relief in patients with a clearly localized pain that was confined to one or two thoracic segmental levels, compared to patients with more than two segmental levels involved in the pain syndrome.