Super voltage pulsed radiofrequency vs thermal radiofrequency for ablation of saddle nerves for treating refractory malignant perineal pain: a singleblind prospective, randomized study

Abstract

Background & objectives: Perineal pain secondary to pelvic malignancies remains a big challenge to the pain
specialists and clinicians. Various management modalities have been used to manage it. This study assessed the
feasibility and effectiveness of selective super voltage pulsed radiofrequency (SVPRF) as a potential alternative to selective thermal radiofrequency (TRF) saddle rhizotomy in patients experiencing refractory perineal pain secondary to pelvic malignancies
Methodology: This prospective, randomized, single-blind comparative study included 60 patients (≥18 years, both sexes) with advanced pelvic malignancies and moderate to severe perineal pain. Patients were equally divided into two groups: Group A: selective saddle rhizotomy via TRF ablation of the S3 nerve root on one side and bilateral S4 and S5 ablation, while Group B: selective SVPRF targeting the saddle nerves at unilateral S3 and bilateral S4 and S5.
Results: Visual analogue scale (VAS) demonstrated a significant decrease at 1, 4, and 12 weeks in group TRF relative to SVPRF group (P < 0.05). The Oswestry disability index was significantly lower at (1 week and 4 weeks) in group TRF relative to group SVPRF (P < 0.05). Functional improvement was significantly higher at 1 week and 4 weeks in group TRF than group SVPRF.
Conclusions: TRF saddle rhizotomy demonstrated superior efficacy over SVPRF in reducing pain, opioid and
pregabalin use, and enhancing function in patients with refractory malignant perineal pain, without increasing
complications or impacting patient satisfaction.
Abbreviations: RF: radiofrequency, SVPRF: super voltage pulsed radiofrequency, TRF: thermal radiofrequency,
Keywords: Super Voltage Pulsed Radio Frequency, Thermal Radiofrequency, Saddle Rhizotomy, Saddle Nerves,
Refractory Malignant Perineal Pain
Citation: Wassef BZT, ElSamahy KAA, Rayad RM, Ghobrial HZ. Super voltage pulsed radiofrequency versus thermal radiofrequency for ablation of saddle nerves for treating refractory malignant perineal pain: a single-blind prospective, randomized study. Anaesth. pain intensive care 2025;30(1):17-24. DOI: 10.35975/apic.v30i1.3097
Received: May 09, 2025; Revised: October 26, 2024; Accepted: January 01, 2025