Pulsed radiofrequency for chronic inguinal neuralgia

Abstract

Background: Chronic inguinal neuralgia has been reported after inguinal herniorrhaphy, caesarean section, appendectomy, and trauma to the lower quadrant of the abdomen or inguinal region. Objectives: This study was designed to evaluate the efficacy of pulsed radiofrequency in management of chronic inguinal neuralgia. Study Design: Randomized, double-blind controlled trial. Setting: Hospital outpatient setting. Methods: Twenty-one patients were allocated into 2 groups. Group 1 received 2 cycles of pulsed radiofrequency (PRF) for each nerve root. In Group 2, after stimulation, we spent the same time to mimic PRF. Both groups received bupivacaine 0.25% + 4 mg dexamethasone in 2 mL for each nerve root. Visual Analogue Scale (VAS) was assessed. Duration of the first block effective pain relief was reported. Repeated PRF blockade was allowed for any patient who reported a VAS > 30 mm in both groups during the one year follow-up period. The number and duration of blocks were reported and adverse effects were also reported. Results: Significantly longer duration of pain relief was noticed in Group 1 (P = 0.005) after the first block, while the durations of pain relief of the second block were comparable (P = 0.59). In Group 1 the second PRF produced pain relief from the twenty-fourth week until the tenth month while in Group 2, pain relief was reported from the sixteenth week until the eighth month after the use of PRF. All patients in Group 2 received 3 blocks (the first was a sham PRF) during the one year follow-up period. Meanwhile, 2 PRF blocks were sufficient to achieve pain relief for patients in Group 1 except 4 patients who needed a third PRF block. No adverse events were reported. Limitations: Small sample size. Conclusion: For intractable chronic inguinal pain, PRF for the dorsal root ganglion represents a promising treatment modality.