Transsacral S2-S4 nerve block for vaginal pain due to pudendal neuralgia.

Pudendal neuralgia is a type of neuropathic pain experienced predominantly while sitting, and causes a substantial decrease in quality of life in affected patients. Pudendal nerve block is a diagnostic and therapeutic option for pudendal neuralgia. Transsacral block at S2 through S4 results in pudendal nerve block, which is an option for successful relief of pain due to pudendal nerve injury. Herein is reported blockade of S2 through S4 using lidocaine and methylprednisolone for successful treatment of pudendal neuralgia in 2 patients with severe chronic vaginal pain. The patients, aged 44 and 58 years, respectively, were referred from the Gynecology Department to the pain clinic because of burning, stabbing, electric shock-like, unilateral pain localized to the left portion of the vagina and extending to the perineum. Their initial pain scores were 9 and 10, respectively, on a numeric rating scale. Both patients refused pudendal nerve block using classical techniques. Therefore, diagnostic transsacral S2-S4 nerve block was performed using lidocaine 1%, and was repeated using lidocaine 1% and methylprednisolone 80 mg after confirming block efficiency as demonstrated by an immediate decrease in pain scores. After 1 month, pain scores were 1 and 0, respectively, and both patients were free of pain at 6-month follow up. It is suggested that blockade of S2 through S4 using lidocaine and methylprednisolone is an effective treatment option in patients with chronic pudendal neuralgia when traditional pudendal nerve block is not applicable.