Most of the pain the pelvic area is mediated by the superior hypogastric plexus. The plexus lies anterior to the body of the L3 to L5 vertebra. It contains postganglionic sympathetic fibers and afferent pain fibers. Innervation of the vagina, rectum, bladder, perineum, vulva, prostate, testes, and uterus arise from this plexus.
What is the purpose of it?
The superior hypogastric block is for the treatment of pelvic pain, either to nonmalignant or malignant pain. Therefore, pain felt to originate from any of these structures could theoretically be treated by blockade of this plexus.
How is it done?
The block is performed under fluoroscopic guidance, with the needles placed anterior to the L5-S1 junction. After an IV is placed in the pre-op area, the patient will be placed in the prone position. Using a live X-ray the position the plexus in the lower back will be identified, and the skin over that area will be numbed by local anesthetics. Under fluoroscopic guidance a needle will be directed to the desired position. Prior to injecting the local anesthetic solution, the correct position of the needle will be confirmed using contrast solution.
How long does the injection take?
The procedure lasts about 20-30 minutes.
What should I expect after the injection?
After the completion of the procedure, Band-Aids will be placed at the injection sites, and a nurse will monitor the blood pressure and pulse and will review the discharge instructions with the patient before going home.
What is injected?
A local anesthetic (numbing medicine) is injected. There may be one or two other types of medicine added to help prolong the block.
Will the injection hurt?
Most patients tolerate the injection very well. Numbing medicine is placed under the skin that feels like a poke and a burn. After that, you most likely will only feel pressure. If you feel any pain during the injection, more numbing medicine can be given. If you choose, you may have intravenous sedation to help you relax. You will likely have some soreness & back pain for 48 hours afterwards.
How many injections do I need?
Usually a series of injections will be needed for treatment if you respond to the first injection. You should be obtaining progressive benefit from the injections as well as physical therapy. Some patients may require over 3 injections where others will require fewer. Months of relief is the goal.