Predictors of the analgesic efficacy of pulsed radiofrequency treatment in patients with chronic lumbosacral radicular pain: a retrospective observational study

Background: Pulsed radiofrequency (RF) targeting the adjacent dorsal root ganglion (DRG) is one treatment option for lumbosacral radicular pain. However, the analgesic efficacy of this procedure is not always guaranteed. The aim of this retrospective study was to identify the predictors of the analgesic efficacy of pulsed DRG RF treatment in patients with chronic lumbosacral radicular pain. Methods: Patients who underwent pulsed DRG RF treatment from 2006 to 2017 at our clinic were enrolled. Positive response was defined as a ≥50% reduction in pain score from baseline at day 30. Patient demographics, pain-related factors, and clinical factors were evaluated using logistic regression analysis to identify the predictors of a positive response to the treatment. Results: A total of 60 patients satisfied the study protocol requirements. Twenty-eight patients (46.7%) had a positive outcome. Multivariate logistic regression analysis revealed that the absence of comorbid musculoskeletal pain (OR=0.518, 95% CI=0.029-0.858, P=0.033) and positive response to previous epidural steroid injection (OR=3.269, 95% CI=1.046-10.215, P=0.042) were independent predictors of the analgesic efficacy of pulsed DRG RF treatment. Conclusion: Comorbid musculoskeletal pain and previous epidural injection response appear to affect the outcome of pulsed DRG RF treatment in patients with chronic lumbosacral radicular pain.