What is Sacral Nerve Stimulation (SNS)?
SNS is a recognised treatment for patients who have severe bowel leakage or bowel incontinence. A small surgical operation places an implant under the skin in the lower back to stimulate the sacral nerves (which control bowel and back passage muscles) using a weak electrical pulse.
Who may benefit from this treatment?
Patients who are most likely to benefit from this treatment often have intact or undamaged anal sphincter muscles (the muscles of the anus) but which are very weak and do not work very well.
It is occasionally used to try to help the symptoms of patients who have severe constipation.
When is this treatment considered?
If other treatments for leakage from your back passage have not worked well and your symptoms are severe, then sacral nerve stimulation may be worth trying. While it will not cure it completely, when it works, it seems to cut the number of leakages.
What tests are necessary before the operation?
We may also perform Anorectal Physiology and Ultrasound studies on the anal sphincter (the anal muscle) to look at its structure and function (how it is working). For these tests small catheters or tubes are gently inserted through the anus and measurements are taken.
A Proctogram is an X-ray that is sometimes required to make sure there is no missed rectal prolapse. This X-ray is a series of images of the way the waste passes through the whole length of the bowel. These tests are x-ray studies that look at how well your large bowel works and to see how the pelvic organs (the organs and area around the rectum) are supported
(how they hold up) when the bowel is emptied.
How do you know that Sacral Nerve Stimulation will work?
The treatment is in two stages. The first is Temporary Sacral Nerve stimulation (where only a wire is placed under the skin). This shows if the treatment is likely be a success before the larger implant (with a stimulator or battery) is put in.

What happens in Temporary Sacral Nerve Stimulation?
A temporary wire is inserted often as a day case procedure and under a local anaesthetic (an injection to the skin to numb it), or sometimes a general anaesthetic (you are put to sleep) is used.
A fine needle is then passed through the skin of your lower back, with you lying on your front. The needle has a weak electrical current passed through it so that the surgeon can find the right place to put the wire so that it can stimulate the nerves. A flexible wire then replaces the needle and is taped under the skin. The other end of this wire is connected to a stimulator the size of a Walkman or Ipod (which the patient wears usually on a belt) and which will send out electrical energy to the nerves of the pelvic floor.
There should not be discomfort and you can return home but you will need to keep a diary record of bowel control and leakages so that we can see if it is working.
When the wire is removed it should not cause any pain.
What are the results like from temporary SNS?
If the treatment works, patients report having fewer leakages. If it seems to be working then we can recommend considering the second stage of treatment, going on to have a more permanent and long lasting implant for SNS (Permanent Sacral Nerve Stimulation). The treatment seems to work in 2 out of every 3 patients.
What if the treatment doesn’t work?
If the treatment does not work you will be sent back to your specialist doctor for further assessment and to look at other treatment options.
Permanent Sacral Nerve Stimulation
The more permanent sacral nerve stimulation is usually performed under general anaesthetic
(you are put to sleep).
Like temporary SNS a wire is inserted to the nerves through the skin of the lower back.
Instead of being brought to the surface and taped into place, this time the wire is tunnelled under the skin and connected to a battery that also sits under the skin. This is carried out by making a small cut in your upper buttock.
The small battery is very much like a heart pacemaker and is about the size of a small matchbox. The device can be removed at any time so that the treatment is reversible.
Recovery after the operation is often rapid with discharge on the same day or the day after surgery.
What are the Benefits of sacral nerve stimulation?
Many people with sacral nerve stimulation have reported:


Improved quality of life
Freedom to live without worry of leaks
You and your doctor can try sacral nerve stimulation without making a big commitment.

.
.
.
Are there any risks?
As with any medical treatment, sacral nerve stimulation may cause you to experience some of these side effects:








Pain at the implant site
Lead movement (when the electrode in the back moves to a different position in relation to the nerves)
Infection or skin irritation
Technical problems with the way the battery works
Jolting or shocking stimulation
Numbness at the battery site
Undesirable stimulation or sensations
In most cases, these issues can be resolved and corrected, so talk to your doctor if you are having any problems.