Pudendal nerve neuralgia from
entrapment/compression is one of the major causes of chronic perineal pelvic
pain. It is a condition similar to carpal tunnel syndrome where the nerve to
the hand is compressed between the ligaments going to fingers causing numbness.
Pudendal nerve entrapment was first recognised in 1987 as the Alcock's canal or
The pudendal nerve is one of the major
nerves to the pelvis and external genitalia. The main symptoms of nerve
entrapment are pain in one or more of the areas supplied by the pudendal
nerve. Typically patients
complains of pain in the perineum (area between rectum and vulva/scrotum),
penis, scrotum in men and vulva, labia, vagina, clitoris in women. The pain is
aggravated by sitting especially on a soft chair, relieved by standing, lying
down or sitting on a toilet seat. The pain is usually described as a severe
burning, tingling pain, increased sensitivity in the area supplied by the
pudendal nerve or it can also be isolated in the rectum, vulva (scrotum) or
clitoris (penile pain).
Patients with pudendal neuralgia may have
symptoms other than pain. This includes pain with urination, urinary frequency,
bowel movement, pain with intercourse or orgasm and sometimes. persistent
sexual arousal. The symptoms of
pudendal nerve neuralgia can mimic and therefore often misdiagnosed as
prostatitis, cystitis, testicular pain, urinary hesitancy, endometriosis and
proctalgia. As a result the average time to diagnosis of pudendal nerve
entrapment is usually about 4 years.
The pudendal nerve can be compressed
between the sacrotuberous and sacrospinous ligaments (clamp), the Alcocks canal
or the falciform process of the sacrotuberous ligament. In approximately 70% of
patients, pain is only on one side and in the remaining 30% the pain is on both
sides of the body.
In many patients, the reason for the injury
of the pudendal nerve is not known. Some of the known causes of pudendal nerve
injury are trauma to the pelvic area, gynecological surgery (hysterectomy,
repair of bladder prolapse, surgery for incontinence), stretching of the
pudendal nerve from chronic constipation, normal vaginal delivery and prolonged
sitting. In cases of surgical
injury, onset of pain is usually sudden but in most cases the onset of pain is
slow and progresses over many months or years.
Diagnosis of pudendal neuralgia is mainly a
clinical diagnosis. There are no exclusive tests for pudendal nerve entrapment.
The criteria (Nantes criteria) used for
1.Pain in the area of the pudendal nerve.
2.Worsened by sitting & relieved by
sitting on toilet or standing.
3.The patient is not woken at night by the
4.No objective sensory loss on clinical
5.Positive anaesthetic pudendal nerve
Some groups use electromyography to test
the nerve function but this can be very confusing and unreliable. Professor Roberts group in Nantes has
stopped using this test for this reason.
Treatment of pudendal neuralgia consists of
conservative and surgical treatments. Conservative treatments include avoiding
activities that caused or aggravate the injury (eg. cycling),
analgesic/anti-inflammatory medications and physiotherapy/chiropractic
If there is no improvement then steroid and
local anaesthetic nerve blocks may be offered. This will reduce the pain as
well as swelling and inflammation around the nerve.