Pudendal nerve block
Neuropathy of the pudendal nerve is a condition where alleviating pain becomes a primary goal. Radical treatment is not suitable for all patients, and pharmacological therapy also has its own peculiarities and limitations, making pudendal nerve block a real find for some patients.
When the pain syndrome becomes chronic, it significantly impacts a person's life: it deprives them of the ability to work comfortably, fully rest, engage in sports, and hobbies. In some cases, pain even triggers psychopathological disorders—most commonly depression—that require separate therapy and greatly reduce the quality of life.
— Tell me, on a scale of 0 to 10, how would you rate the level of pain?
The patient is contemplating. Initially, this question stumps her. The comparative scale is used in many areas of medicine — to measure pain, discomfort, the intensity of sensations during limb numbness, and even depression. But at first, it can be difficult for a person to correlate what they're feeling with a specific number.
— Five… or eight? I don't know how to count. It hurts a lot.
— This is a very useful diagnostic technique. With its help, we can assess how effective the chosen therapy is. Let's use a comparison. For example, just below the middle of the scale, mark 4 — that's pain, in terms of intensity, identical to what you experience with pulpitis or a severe bruise. You can work, but you're constantly aware of the pain and can't adapt to it. It's always a part of your life.
— The latter — perhaps, but a tooth… Is that a 4?
— Yes. A similar level of pain can be simulated by pinching the skin fold between the thumb and forefinger of the other hand, squeezing tightly, and digging in with the nails.
The patient tries to mimic.
— Not quite enough. Maybe an 8?
— It shouldn't be difficult for you to imagine this. It seems you're a mother? "Eight" is often compared to childbirth.
— And what's a 10 like?
— One of my colleagues compares the sensations of a "ten" to those of a person immersed alive in concentrated acid.
— I haven't experienced that yet, — the patient tries to smile.
— I hope you never will. It's a level of pain people rarely experience. For example, if you're in a serious accident and sustain severe injuries — to the point where your bones are shattered.
— Okay, I understand. Let's rate the pain at a six. It greatly interferes with life, and sometimes I even find it hard to think. It's usually dull, but one awkward movement — and it's not easy to soothe for a long time.
— Are you considering a nerve block?
— Yes, if it helps… I've read that there can be side effects.
— Unfortunately, that's possible. The effectiveness of the procedure, according to various studies, ranges from 40 to 75%. And I must warn you that you shouldn't rush to evaluate your condition immediately after taking the medication — at first, you may experience discomfort, and it may take time for us to see the effect. So, I'll expect you back in a week for a follow-up appointment after the procedure.
A week later, the same patient shares her impressions:
— The first few hours after the injection were wonderful — there was no pain at all until the anesthetic wore off. But then it came back. Right now, I would rate it at 3 or 4.
— Has it gotten easier for you?
— Definitely. And, I would say, I've gotten used to it, endured it. In any case, if I can settle comfortably and avoid sudden movements, life is much more comfortable. Can I do this regularly?
— We need to monitor your condition to understand how the nerve block is working. I'll wait for you to feel any changes in your sensations and then we'll decide what to do next.
The features of pudendal nerve block
Blockade is an injection of a special medication aimed at disrupting the transmission of pain signals throughout the patient's body. The anesthetic is injected precisely into the tissue area near the pudendal nerve. Since the pudendal nerve is small and varies in location among different individuals, basic knowledge of anatomy is insufficient for a quality and effective blockade.
Additional investigations are required to understand where, at what angle, and to what depth the needle should be inserted. These investigations include:
- Tomography (CT, MRI),
- X-ray,
- Ultrasound.
These examinations are mandatory because without them, it is impossible to determine the correct position of the syringe during the procedure. Neglecting precision can result in incorrect administration of the medication, leading to no effect, as the anesthetic zone will be too far from the intended area. There is also a risk of damaging the nerve and worsening the situation.
Blockade is considered palliative therapy, meaning its goal is not the complete recovery from the disease but rather the improvement of the patient's quality of life and pain relief. The technology continues to advance — for example, in the 2010s, the procedure began to be performed with dynamic fluoroscopy, allowing the confirmation that the medication is delivered precisely to the affected area during administration.
Types of blockade, medications, and injection technique:
There are two main types of injectable medications used for blockade in the treatment of pudendal nerve neuralgia. They are used depending on the goal, as the blockade can be:
The duration of the procedure depends on many factors. It may be temporary or even permanent, so many doctors prefer to take breaks between blockades: if the nerve is not irritated, steroids will not work.
The most common injection sites include:
- The ischial bones between the sacrotuberous and sacrospinous ligaments,
- Alcock's canal.
Some doctors perform nerve blockade on the dorsal penile/clitoral branch of the pudendal nerve.
Risks associated with pudendal nerve blockade:
Sometimes, a reaction contrary to the desired one is possible — an increase in pain sensations for several days or weeks. Some people who have undergone nerve blockades have experienced prolonged worsening of symptoms:
- Increased pain in a sitting position
- A condition called persistent genital arousal syndrome (without sexual desire)
The unwanted consequences may result from "pinching" the pudendal nerve with the needle of the syringe, as well as a reaction to medications or scar tissue formation.
Expected effect:
During the pudendal nerve blockade performed under patient control, the patient is placed in a lying position. When the pudendal nerve is identified, a short-acting anesthetic and steroid are injected. Control can be achieved using ultrasound, CT, and other techniques.
The procedure takes about half an hour and is performed on an outpatient basis — the patient can go home soon afterward. If it has been established that the cause of the pain lies in pudendal nerve pathology, therapeutic blockade with steroids is performed. The effect of the procedure can last for several months, after which the injection may need to be repeated or another therapy option chosen.
If the blockade was diagnostic, pain relief indicates that the diagnosis was correct. In the absence of results, two scenarios are possible:
- The cause of the pain lies elsewhere, and the pudendal nerve is healthy
- The medication did not reach a zone close enough to the nerve, thus failing to relieve symptoms.
If there is no loss of sensation in the target area, the doctor may prescribe another blockade. This is done to completely exclude the possibility of pudendal neuralgia.
