Pudendal neuralgia is defined as a painful neuralgia caused by a lesion or compression of the pudendal nerve, a peripheral nerve that arises from the sacral plexus.

Historical

Historically, pudendal neuralgia was first identified in competitive cyclists and was termed the „cyclist's syndrome“ or „Alcock canal syndrome“ by the French psychiatrist Gérard Amarenco in 1988[^4]. Later findings showed that pelvic injuries could also trigger this condition in other patient populations[^3].

Epidemiology

The prevalence of pudendal neuralgia is estimated to have an incidence of 1 / 100,000 and is more commonly observed in women than in men[^3].

Etiology

Pudendal neuralgia can be caused by mechanical injuries, viral infections, or immunological processes. Mechanical causes can result from muscle spasms in the pelvic floor (levator ani muscle or obturator internus muscle), pressure from surrounding ligaments (sacrospinous or sacrotuberous ligament), or scar tissue due to trauma or surgery. During surgical procedures, entrapment can also be caused by meshes or sutures that directly damage the nerve. In women, the most common causes of pudendal neuralgia are surgical injuries, particularly from gynecological procedures such as vaginal surgery for prolapse or incontinence, pelvic injuries (e.g., from heavy lifting, falls, or insertion of foreign objects), and less frequently vaginal childbirth. In men, on the other hand, pelvic injuries are the most common cause of pudendal neuralgia[^3].

Symptoms

Patients with pudendal neuralgia report neuropathic pain in the area innervated by the pudendal nerve. The pain is often described as burning or sharp, stabbing pain between the testes/labia and anus. These pains typically worsen when sitting on a chair, but not when sitting on the toilet. Digital rectal palpation of the sacrospinous ligament exacerbates the pain symptoms[^1] [^2].

Diagnostics

In addition to imaging of the pudendal nerve, further diagnostics can include an EMG examination as well as CT-guided blockade of the pudendal nerve[^1].

The typical clinical diagnosis of pudendal neuralgia can be made according to the Nantes criteria, which are composed as follows[^2]:

Pain in the anatomical territory of the pudendal nerve.
Increase in pain symptoms when sitting.
The patient does not awaken at night due to the pain.
No objective hypoesthesia in clinical examination
Positive response to a pudendal nerve block

Treatment

The treatment of pudendal neuralgia can be conservative, such as with CT-guided blockade, or surgical with neurolysis[^1].