A Novel Approach to Blocking the Pudendal Nerve Using Neurostimulation to Increase Accuracy and Efficacy

AlopiM. Patel, MD ; Amber G. Hampton, MD; Stephanie G. Vanterpool, MD, MBA, FASA 

Introduction

Pudendal Nerve Block is the diagnostic and therapeutic treatment ofchoice for chronic pelvic pain caused by pudendal nerve irritation orentrapment.

The pudendal nerve arises from the ventral rami of thesacral spinal nerves S2-S4, and gives off three consecutive branches as it exitsAlcock’s canal- the inferior rectal (anal) nerve; the perineal nerve; and thedorsal nerve of the penis or clitoris.

These nerves innervate the regions ofthe rectal canal, anus, perineum, and external genitalia, including the clitorisand penis, labia minora, vaginal vestibule, and the lower one-fifth of the vaginalcanal, as well as the posterior aspects of the labia majora and scrotum.

Theanatomic variation of the branches of the pudendal nerve can make a uniformed approach topudendal nerve block somewhat ineffective if the correct branch has not been anesthetized.

Wedescribe a novel approach to the pudendal nerve block using nerve stimulation guidance to preciselytarget the branches of the nerve that are concordant with the patient’s painful area.

We present a case series of 5 patients with varying pain locations, all innervatedby the pudendal nerve, and describe the precise needle locations that producedconcordant nerve stimulation and successful pudendal nerve block.