Pudendal Nerve Irritation

Pudendal nerve irritation (neuralgia or nerve entrapment) is defined as pain in the distribution of the pudendal nerve, specifically the rectum, vagina, penis, perineum, and mons pubis. It can refer to nearby areas in the pelvis, but the predominant area of pain is in the areas described above.

Pudendal nerve entrapment occurs when there is something physically compressing the pudendal nerve along its pathway. This can occur as a result of a traumatic injury to the pelvis, where the pudendal nerve can become entrapped between the sacrospinous and sacrotuberous ligaments, or anywhere else along its pathway. It can also occur after a traumatic childbirth, especially from a forceps delivery, or other instrumentation during the birthing process. The third scenario that could potentially result in pudendal nerve entrapment is post-surgical entrapment, where a stitch may have been inadvertently introduced into the path of the pudendal nerve.

If these criteria are not met, and the pain is predominately in the distribution of the pudendal nerve, then pudendal neuralgia is a more likely diagnosis.

The major criteria that need to be present for the diagnosis for pudendal neuralgia are as follows:

1. Pain in the territories of at least two out of the three terminal pudendal branches.
   • There are three branches of the pudendal nerve on each side of the body.
   • The dorsal (clitoral or penile) branch, the perineal branch (middle branch), and the rectal branch.
2. Positive Tinel’s sign (tapping of the ischial spine internally which produces the patient’s typical pain).
3. Sexual arousal syndrome (may only be present in some patients).
4. Positive CT-guided pudendal nerve block; in other words, the pudendal nerve block temporarily abolished or significantly reduced the typical pain that the patient is reporting.

If the pudendal nerve is thought to be entrapped, the following criteria need to be met:

1. The pain is experienced predominately while sitting.
2. The pain does NOT wake the patient up at night (this is very important criteria).
3. The pain does not correlate with any objective sensory impairment(such as numbness).
4. Thepain is reduced by a pudendal nerve block (CT-guided).

If a patient has signs of a sensitive nervous system, they may not respond as well to surgery. Scoring less than 40 on the Central Sensitization Inventory would indicate a better prognosis with surgery. Furthermore, patients who have other co-morbid conditions that are highly correlated with a sensitive nervous system would also not do as well with surgery.  These concurrent conditions would include vulvodynia, endometriosis, BPS/IC, chronic non-bacterial prostatitis, idiopathic low back pain, fibromyalgia, temporo-mandibular joint pain, and migraine headaches.

Pudendal neuralgia and pudendal nerve entrapment often involve a component of biomechanical dysfunction in the SI joint, Pelvic Floor Muscle Weakness and connective tissue dysfunction. If you are going to consider a pudendal nerve block, you should see a pelvic floor physiotherapist first to ensure that the “container” of the pudendal nerve (muscles, connective tissue, and bony structures of the pelvis) are healthy so the effect of the nerve block can be accurately assessed. If these structures are still tight, you will likely not find relief from the block, even though the pudendal nerve may be truly involved. Furthermore, neural tension of the pudendal nerve should be assessed and treated prior to and after a pudendal nerve block by a pelvic floor physiotherapist. Neural tension exercises will help to ensure that the pudendal nerve is gliding smoothly within its container.

Pudendal neuralgia, or entrapment, has been compared to complex regional pain syndrome (CRPS), a sympathetically-mediated pain syndrome. There are significant changes in the nervous system that occurs with these pain syndromes, and the sensitive nervous system must be addressed to get full resolution of these symptoms.

The term “pinched nerve”, or nerve entrapment, can be very scary. Sometimes, the diagnosis itself can create its own set of problems. The more you learn about your protective nervous system, the better you will be able to restore the nerve to normal function again.