Pudendal Nerve Block With Articaine and Triamcinolone for Pudendal Neuralgia

Overview

This study is testing whether an injection of local anesthetic (articaine) combined with a steroid (triamcinolone), placed near the pudendal nerve under ultrasound guidance, can reduce pain in people with pudendal neuralgia - a chronic pain condition affecting the perineal area - when other treatments (such as medications and physical therapy) have not worked well enough. Participants are randomly assigned to receive either the active injection (articaine and triamcinolone) or a placebo injection (saline solution), without knowing which one they receive. Neither the participant, the person performing the injection, nor the person assessing the results afterward knows which group the participant is in. The main question the study is trying to answer is whether more people report at least 50% less pain four weeks after the injection with the active treatment compared with placebo. The study also looks at quality of life, sleep, physical function, use of pain medication, and side effects over 24 weeks after the injection.

This is a single-center, prospective, randomized, placebo-controlled, parallel-group trial conducted at Kharlampiev Clinic (Irkutsk, Russia), a clinical base of Irkutsk State Medical University. Patients meeting the clinical Nantes criteria for pudendal neuralgia, with pain refractory to conservative therapy, are randomized 1:1 to receive a single ultrasound-guided transperineal pudendal nerve block with either articaine 5 mL (20 mg/mL with epinephrine 1:200,000) plus triamcinolone acetonide 40 mg, or an equal volume of 0.9% saline (placebo), both brought to a total volume of 10 mL with saline. Randomization is performed using a computer-generated sequence with a fixed block size, by an independent staff member not involved in patient care or outcome assessment. Study medication is prepared by a designated unblinded staff member; the treating physician, outcome assessor, and participant remain blinded to group assignment throughout the study. The primary outcome is the proportion of participants achieving a reduction of more than 50% in pain intensity on a 0-10 Numeric Rating Scale (NRS) at 4 weeks after the injection. Secondary outcomes include NRS pain scores at 1, 2, 8, 12, and 24 weeks; quality of life (EQ-5D-5L); sleep quality (Pittsburgh Sleep Quality Index, PSQI); pudendal neuralgia-specific functional status (PNEQ); rescue analgesic use; and treatment-related adverse events over 24 weeks of follow-up.