Pudendal canal syndrome, also referred to as pudendal pain, is an irritation affecting the pudendal nerve, an important nerve of the pelvic floor. Pain is the predominant symptom of pudendal canal syndrome, while motor disturbances, affecting movement or vesical control, are rare.
The Pudendal canal syndrome
The classical cause of pudendal pain is chronic pressure exerted on the nerves in the pudendal or Alcock's canal. Such pressure may result from using a poorly adapted bicycle seat or engaging in some extended activity in a sitting position. In some cases, giving birth may also lead to pudendal pain. Such a complication may arise if the pudendal nerve is compressed subsequent to postpartum haemorrhage, in the case of scarring in the pudendal canal (as a result of haemorrhage or infection) or because of pudendal nerve stretching during labour. The latter scenario may occur if the weight of the newborn is over 4 kg, if the expulsive labour lasts more than 30 minutes, and often in the case of forceps delivery.
Pudendal canal syndrome may also develop as a result of pudendal nerve adhesion following vaginal descent surgery or pelvic radiotherapy in gynaecological malignancies.
Typical symptoms of pudendal canal syndrome include pain in the left or right buttock that is amplified in a sitting position.
Pudendal pain is typically treated by decompression of the pudendal nerve. Treatment options include transgluteal or transperineal surgery or abdominal laparoscopy. While the pudendal canal is most easily accessed through the perineum, if surgery must be performed deep in the small pelvis, complete access is not possible. The same limitation exists with transgluteal surgery. In such cases, for example when the complete resection of deep endometriosis or adhesions is required, laparoscopy offers an optimal approach. Laparoscopy can also be used to treat different causes of pain associated with surgical lesions of the pudendal nerve or sacral root (such as the removal of pins, sutures or scar tissue).
Neuromodulation is another therapeutic option to treat pudendal pain. The LION procedure developed by Prof. Possover allows neuromodulation of the sacral nerve roots which contain pudendal nerve fibres.
Sacral neuromodulation is the therapeutic option of choice in the following clinical cases:
- Failure of pudendal nerve neurolysis
- Neurological conditions, such as multiple sclerosis, Parkinson’s syndrome or diabetic neuropathy (neurological disease caused by diabetes).
- As a follow-up procedure to pelvic surgery, when pain cannot be explained by any other cause, such as the presence of pins or sutures.