Comparative long-term efficacy of short-term spinal cord stimulation versus bipolar pulsed radiofrequency for refractory postherpetic neuralgia: a 24 month prospective study

Abstract

Background: Postherpetic neuralgia (PHN) is a debilitating neuropathic pain condition that persists after herpes zoster infection, often resistant to conventional medications. This study compares the long-term efficacy and safety of short-term spinal cord stimulation (stSCS) versus bipolar pulsed radiofrequency (bPRF) in managing refractory PHN.

Methods: In this prospective, controlled observational study, 140 PHN patients (aged ≥ 18 years; PHN duration ≥ 3 months) with inadequate pain relief from standard therapies were enrolled and randomized equally into two groups (n = 70 each). The stSCS group received percutaneous implantation of an 8-contact electrode for temporary neuromodulation, while the bPRF group underwent application of controlled high-frequency pulses to the dorsal root ganglion. Outcome measures included pain intensity (VAS, NRS), neuropathic pain characteristics (DN4), quality of life (SF-36, EQ-5D), sleep quality (PSQI), and psychological status (SAS, SDS), assessed at baseline and at follow-up intervals over 24 months.

Results: Both stSCS and bPRF achieved significant short-term pain relief. However, from 6 to 24 months post-treatment, the stSCS group demonstrated significantly lower VAS scores and superior pain control compared to the bPRF group. In addition, improvements in sleep quality and emotional well-being were more pronounced in the stSCS group at 12, 18, and 24 months. Both treatments exhibited favorable safety profiles with only minor, transient adverse events reported.

Conclusions: While both stSCS and bPRF effectively alleviate pain in patients with refractory PHN, stSCS offers superior long-term benefits in pain reduction, sleep quality, and psychological outcomes. These findings suggest that stSCS may be the preferred neuromodulation strategy for patients with chronic PHN requiring sustained symptom management.

Keywords: Bipolar pulsed radiofrequency; Pain management; Postherpetic neuralgia; Short-term SCS.

Fig. 1

CONSORT flow diagram of patient enrollment and follow-up. This figure illustrates the study flow from initial screening to patient allocation and follow-up. A total of 140 patients were enrolled and equally distributed between the stSCS and bPRF groups. The diagram details the number of patients assessed for eligibility, exclusions (with reasons), allocation to treatment arms, and follow-up at designated intervals (1, 3, 6, 12, 18, and 24 months)

Fig. 2

Fluoroscopic views of electrode placement for stSCS and bPRF. A Anteroposterior fluoroscopic view demonstrating the implantation of spinal cord stimulation electrodes; B lateral fluoroscopic view showing the electrode trajectory along the spinal column; C anteroposterior view illustrating the placement of bipolar pulsed radiofrequency needles at the target site; D lateral view confirming the accurate positioning of bipolar pulsed radiofrequency needles relative to vertebral structures

Fig. 3

Longitudinal changes in pain scores (VAS) over 24 months. This figure displays the mean VAS scores for both the stSCS and bPRF groups at baseline and subsequent follow-up intervals (1, 3, 6, 12, 18, and 24 months). Error bars represent standard deviations. The graph highlights that, while both groups showed significant short-term pain relief, the stSCS group maintained superior pain control over the long term (p < 0.05 from 6 months onward). Asterisks denote statistically significant differences between groups at the corresponding time points

Fig. 4

Sleep and mental health outcomes at 24 months. This figure summarizes the improvements in sleep quality and mental health parameters at the 24 month follow-up. Bar graphs represent the PSQI, SAS, and SDS scores for both treatment groups. The stSCS group demonstrated significantly greater improvements compared to the bPRF group, with *p < 0.05 indicating statistically significant differences between the groups