What is a Ganglion Impar Block?
The ganglion is an area where multiple nerves come together. These nerves send all kinds of signals to the brain, including pain signals and other sensory information. The ganglion impar sits in front of the sacrum, the bony triangle located at the base of your spine.
Nerves in the ganglion impar control functions and response in the:
- Anal area
- Lower part of the urethra
- Vagina and vulva
- Scrotum
- Tailbone
- Lower area of the rectum
When there is chronic pain in any of these areas, a ganglion impar block can help. A ganglion impar block uses a local anesthetic for pain and a steroid for inflammation that is injected into the ganglion impar to disrupt pain signals.
A ganglion impar block can be used diagnostically as well. If the cause or exact location of your pelvic pain has not yet been diagnosed, a successful ganglion impar block can help pinpoint the source of pain as occurring in this area.
Why is a Ganglion Impar Block performed?
The most common causes of pelvic and groin pain include:
- Cancer in the vagina or vulva
- Rectal or anal cancer
- Cancer in the scrotum
- Tailbone pain
- Pain in the rectum
Ganglion impar blocks are frequently used for diseases in the pelvic and groin area, however, injury or trauma – such as car accidents or sports injuries – to this area can also be treated with a ganglion impar block. A ganglion impar block can help provide relief.
These blocks have also provided relief for one of the 21st century’s “sitting diseases”: coccydynia, which is pain that is caused by improper or excessive sitting postures. It can also occur when a person stands incorrectly for an extended period, causing pain in the tailbone that usually responds to conservative treatments. When it does not, a ganglion impar block can provide relief.
Results depend on the individual patient, their overall health, and any underlying conditions, but many patients experience near total long-term pain relief. The benefits of a ganglion impar block can be temporary for some people, and the amount and duration of pain relief varies from person to person. Some have relief for weeks; others benefit from the block for years.
The procedure is a low-risk, non-surgical treatment that, if successful the first time, will most likely continue to provide pain relief with repeat treatments.
How is a Ganglion Impar Block performed?
Laying face-down on the examination table, your doctor will clean and sterilize the injection site. The doctor will give you an injection of local anesthetic to make the procedure is completely pain-free, which may sting briefly but will quickly become numb.
Using fluoroscopic (X-ray) guidance to ensure proper placement, a needle will be inserted into the area around your tailbone, stopping when it reaches the ganglion impar—the injection target. A small amount of contrast dye is injected first, which shows up on an X-ray and is another way to make sure the injection is in the right spot.
Finally, your doctor will inject medication, usually an anesthetic and a steroid, into the ganglion impar. You may feel a warmth or a burning sensation at the injection site.
Following the procedure, you will rest for 30 minutes to an hour while your vital signs (heart rate, blood pressure, and oxygen level) are monitored. This is an outpatient procedure, and you will be released to go home shortly after it’s completed.
This is a very low risk procedure, but there are some potential risks, including:
- Bleeding from a misplaced injection
- Nerve injury or paralysis
- Puncture of surrounding organs (including rectum)
- Puncture of nearby vessels
- Drug allergy and seizure (if the medication is injected into a blood vessel) are possible but rare, as is the risk of infection.
In some cases, patients will find no pain relief. If this occurs, your doctor may try the injection from another approach.
What should I expect after a Ganglion Impar Block?
Make sure you have a friend or family member to drive you home after the procedure, because you will receive light. Take it easy on the day of your procedure and avoid strenuous exercise or activity for at least 24 hours. Check with your doctor for specific recovery instructions. In general, keep these things in mind as you heal from your ganglion impar block.
- It’s normal to have some pain at the injection site after the procedure, which should gradually decrease over a few days. Icing the injection site can offer comfort if you are sore.
- Do not swim or soak in a bathtub until the injection site heals.
- You can eat and drink normally directly after the procedure.
- You can resume taking most medications after the ganglion impar block procedure but check in with your doctor to be sure.
As noted above, side effects are rare. Serious ganglion impar block side effects even rarer. Contact your doctor immediately if you experience any of the following in the days after your block:
- Severe pain
- Weakness or numbness in the legs
- Changes in bowel or bladder function
- Fever
- Redness, swelling, and oozing at the injection site
