Effect of steroid dose on efficacy of CT-guided pudendal nerve blocks for pudendal neuralgia

Abstract

Purpose: The aim was to determine the impact of steroid dose on effectiveness of CT-guided pudendal nerve blocks. Secondary aim was to assess predictors for response. Materials and methods: A retrospective cohort study was performed. Two-hundred-and-seventeen patients with pudendal neuralgia were identified. Of these, 189 patients had data on response and 511 pudendal nerve blocks were analyzed. Demographics, social history, initial pain data, treatment data including steroid dosing, and follow-up data were collected. Non-responders to treatment were compared to responders. Results: The majority of patients were female (92.1%) and most common areas of pain involved the vulva/labia/ perineum/vagina (scrotum) (44.2%). Treatment response rates increased with number of blocks with maximum response rate of 92.2% after fourth injection. Responders underwent more blocks within the first year (3.1 ± 1.5 vs 2.6 ± 1.6, p = 0.026). Steroid dose did not have a significant effect on response rate nor did site of injection. Non-responders were more commonly on disability due to pain ( p = 0.043). History of childhood/adolescent sexual abuse was more common in non-responders (p=0.046) and was a significant predictor of response (OR = 0.27 [0.08–0.94 95% confidence interval], p = 0.04). Conclusion: Steroid dose does not appear to have an impact on the short-term response rates to CT-guided pudendal nerve blocks in patients with clinically diagnosed pudendal neuralgia and our data may further support the discontinuation of steroids from CT block protocols. Current long-term disability leave status was a predictor of poor response along with history of childhood/adolescent sexual abuse. Adverse childhood events are easily assessed and may represent a clinical predictor of lack of response in this patient population. Clinical relevance: Approaches to managing pudendal neuralgia are varied. Steroid dose may not impact response to pudendal nerve blocks. Current disability status and history of childhood/adolescent sexual abuse may be clinical predictors of poor response to treatment.