Pudendal Neuralgia
Health Organization for Pudental Education
Overview of Symptoms
The main symptom of pudendal neuralgia (PN) and pudendal nerve entrapment (PNE) is pain in one or more of the areas innervated by the pudendal nerve or one of its branches. These areas include the rectum, anus, urethra, perineum, and genital area. In women this includes the clitoris, mons pubis, vulva, lower 1/3 of the vagina, and labia. In men this includes the penis and scrotum. But often pain is referred to nearby areas in the pelvis.
The symptoms can start suddenly or develop slowly over time. Typically pain gets worse as the day progresses and is worse with sitting. The pain can be on one or both sides and in any of the areas innervated by the pudendal nerve, depending on which nerve fibers and which nerve branches are affected. The skin in these areas may be hypersensitive to touch or pressure (hyperesthesia or allodynia).
Possible symptoms include burning, numbness, increased sensitivity, electric shock or stabbing pain, knife-like or aching pain, feeling of a lump or foreign body in the vagina or rectum, twisting or pinching, abnormal temperature sensations, hot poker sensation, constipation, pain and straining with bowel movements, straining or burning when urinating, painful intercourse, and sexual dysfunction – persistent genital arousal disorder (genital arousal without desire) or the opposite problem – loss of sensation.
It is not uncommon for PN to be accompanied by musculoskeletal pain in other parts of the pelvis such as the sacroiliac joint, piriformis muscle, or coccyx. It is usually very difficult to distinguish between PN and pelvic floor dysfunction because they are frequently seen together. Some people refer to this condition as pelvic myoneuropathy which suggests both a neural and muscular component involving tense muscles in the pelvic floor.
Possible Causes of PN
There are numerous possible causes for pudendal neuropathy. Some of the possible causes are an inflammatory or autoimmune illness, frequent infections, tension on the nerve, a nerve entrapment similar to carpel tunnel syndrome, or trauma to the nerve from an accident/fall, exercise, childbirth, prolonged sitting, or surgery. Sometimes there is no apparent explanation and some doctors have theorized that the problem can be hereditary due to a musculoskeletal predisposition. Occasionally the problem originates in the spine or sacral area rather then the peripheral pudendal nerve.
Pudendal neuralgia can be caused by inflammation of the nerve or by mechanical damage/trauma to the nerve. Sometimes the pain develops slowly and is almost imperceptible at first, sometimes preceded by paresthesia in the area innervated by the pudendal nerve. Paresthesia is a “pins and needles” sensation or a feeling of prickling, numbness, and tingling.
Many people however recall one event in particular as the beginning of their symptoms. Some recall the feeling of a lightning electrical shock after a bad move. Some people report their symptoms started after direct shock like a fall on the buttock or a car accident. Others report pain after a sacral surgery such as a sacroiliac joint fusion resulting in a tilted pelvis or a pelvic surgery such as a sacrospinal fixation. Sometimes there is direct trauma to the nerve either from retractors or misplaced sutures. Pelvic surgery such as a hysterectomy may trigger pudendal neuralgia even though the nerve was not touched directly. One theory is that the nerve can undergo a stretch injury if the body is in a certain position for a long period of time during surgery. Sometimes women develop pudendal nerve pain immediately following childbirth and while often this eventually subsides, for some women the pain does not go away. Women with severe endometriosis may develop scarring or inflammation if the endometriosis settles on the nerve.
Prolonged sitting at work and frequent long drives are a common cause of compression to the nerve. Sports involving repetitive hip flexion like heavy weight lifting may cause enlarged or strained ligaments or enlarged muscles that impinge on the nerve. Some young athletes have been shown to have an elongated ischial spine, a bone that protrudes into the pelvis near the pudendal nerve. Cycling is a leading favorable risk factor for the development of the condition. In the sports medicine community it is sometimes called “cyclist syndrome”.
One hypothesis suggests that people who have PN were predisposed to have it and something occurred that triggered it. Other people who are predisposed may never develop the condition if they never engage in an activity or experience an incident that triggers it. For instance, someone who is predisposed to PN may take up weightlifting and consequently develop PN while another person who is predisposed but does not weight lift will not develop PN.
Tight muscles, tendons, or enlarged ligaments can lead to constant friction on the nerve or if the pelvis is out of alignment there may be undue pressure on the nerve. For some, the pudendal nerve can follow an irregular path or they may naturally have a tight space between the ligaments at the ischial spine or in the alcock’s canal. Some doctors have seen PN run in families, with several members in successive generations developing PN. Some people tend to form excessive scar tissue and this may lead to entrapment of the nerve. Certain autoimmune or inflammatory illnesses have been linked to pudendal neuralgia.
However, sometimes the cause remains unknown.
http://www.pudendalhope.info/node/9
Anatomy
• The pudendal nerve is made up of branches from the anterior sacral nerve roots (S2, S3, S4) and sympathetic fibres from the lower sympathetic chain.
• These nerves join together to form a single nerve about 1 cm behind the ischial spine. The nerve leaves the pelvis by passing through the greater sciatic foramen just below the piriformis muscle.
• It then crosses behind the attachment point of the sacrospinous ligament to the ischial spine, and the re-enters the pelvis through the lesser sciatic foramen.
• It then runs forward on the inner surface of the pelvis, in the pudendal canal (also known as Alcock’s Canal) together with the internal pudendal artery.
• The pudendal nerve has 3 branches, each supplying different parts of the perineum:-
1. Inferior anal branch – supplies the external anal sphincter and perianal skin
2. Perineal branch – supplies labial (or scrotal) skin, pelvic floor muscles, and erectile functions in the clitoris (or penis).
3. Dorsal nerve of the clitoris (or penis) – supplies sensation and erectile functions to these organs and also the urethra.