What is Ilioinguinal Neuralgia?
Ilioinguinal neuralgia is a common source of lower belly and upper thigh pain, usually due to damage or injury to a particular nerve. The nerve in question, the ilioinguinal nerve, is found running along your abdomen from your lower back down to the top of your hip. This nerve travels through several muscles in your abdomen and becomes surface-level near some important areas. In men, it’s near the spermatic cord (the tube that carries sperm from the testicles), and in women, it’s near the round ligament (a cord-like structure that connects the uterus to the groin). Along its path, the ilioinguinal nerve helps control movement and carries sensations from specific sensitive regions in males and females, including parts of the genital area and a small section of the upper thigh.
The complex path of the ilioinguinal nerve makes it susceptible to damage or entrapment, particularly following certain surgeries in the lower abdomen. Both male and female patients may experience varying amounts of pain, a tingling sensation known as paresthesia, and abnormal sensations in the areas supplied by the nerve.
Diagnosing ilioinguinal neuralgia involves a thorough patient history review, physical exams, and specialized tests including electrical studies of the nerve and ultrasound imaging. Initial treatment typically begins with non-invasive approaches, such as pain medications, anticonvulsant drugs, physical therapy, and techniques to relieve muscle tension. If these conservative treatments do not lessen the symptoms enough, other therapeutic options like localized nerve block procedures, cryotherapy (use of cold for treatment), or radiofrequency ablation (a procedure that uses radio waves to reduce pain) may be helpful. In severe cases where other treatments do not work, part of the nerve might need to be surgically removed, a procedure known as a neurectomy.
What Causes Ilioinguinal Neuralgia?
There are several medical procedures and conditions that could potentially cause damage to the ilioinguinal nerve, which is one of the major nerves in your hip and groin area. These include:
- Abdominoplasty (a tummy tuck)
- Routine surgeries like removing the appendix or the uterus, especially when done through a certain type of incision called a Pfannenstiel incision
- Severe injury to the abdomen
- Placing a tube (catheter) into a large vein in the thigh
- Repairing a groin hernia
- Damaging the connective tissue that connects the lower part of the oblique muscles (this might happen, for example, among hockey players)
- Performing surgery on the testicles using an approach through the groin
- Physical stresses during pregnancy
- Inserting a pointed instrument (a trocar) during keyhole surgery.
Additionally, the ilioinguinal nerve could also become trapped and cause discomfort. This usually happens because of abnormalities in the connective tissues that surround the muscles due to tight layers of fibrous tissue (fascial planes). The usual sites where the nerve could become entrapped include the top of the hip bone (iliac crest), the groin area, near the spine, and the edge of the muscle that runs down the middle of the abdomen (rectus border muscle).
Risk Factors and Frequency for Ilioinguinal Neuralgia
Ilioinguinal neuralgia is a common source of ongoing lower tummy and front pelvic pain. Often, it’s seen after surgical repair of an inguinal hernia, which happens due to the nerves being stretched or trapped. It’s not often due to these two conditions. Every year in the United States, about 800,000 hernia operations take place. Out of these, 12% result in long-term pain and 2% lead to significant ilioinguinal neuralgia. It’s also worth mentioning that in terms of global figures, between 18% to 24% of people might experience ilioinguinal neuralgia at some point in their lives.
Signs and Symptoms of Ilioinguinal Neuralgia
Ilioinguinal neuralgia is a type of nerve pain that can lead to significant discomfort and disability. The diagnosis is important for effective treatment and is typically based on patient history and physical examination.
A patient with ilioinguinal neuralgia might complain about pain, which could be a result of surgery, in the lower abdomen, on the side of the hip bone (iliac fossa), and upper thigh. There could also be abnormal sensitivity (hyperesthesia) or lack of sensitivity (hypoesthesia) in the skin in the area where the ilioinguinal nerve is distributed.
Patients may experience muscle weakness in the front and inside part of the thigh. Other common symptoms include pain that radiates from the groin area to the lower abdomen and thighs but does not go beyond the knees. Groin pain might also reflect on the inner thighs, the scrotum in men, or the outer parts of the female genitalia (labia majora).
Characteristics of the pain can vary a lot. Some increase discomfort with hip extension, leading to a bent-forward walking posture due to the strain on the surrounding muscles and the nerve affected. The emergence of such nerve pain can be traced back to a distinct episode of trauma or surgery. The onset of symptoms could be immediate or delayed by weeks, months, or even years.
- Additional signs of ilioinguinal neuralgia include: hair loss and changes in the anterior surface of the male genital region or the female genital region.
- There could be abnormal hypoesthesia or hyperesthesia on the inner front thigh and along the groin ligament.
- There may be pain in the scrotum or labia majora, inner thigh, or medial groin. This vein is often related to a specific trauma or surgical procedure.
- Pain might move towards the lower abdomen.
- Up to 75% of patients might identify pain when gently applied pressure to the external ring, a structure in the groin area. Pain could also be reproduced by touching the region just inside the anterior superior, a prominent bone point on the hip.
- Weakness of the muscles in the upper front and inner thigh, which is supplied by the ilioinguinal nerve, could be noticed.
During physical examination, the doctor may find tenderness when touching one inch inside and below the bone prominence on the hip on the affected side, or on direct pressure over the external ring. A thorough neurological examination is important to rule out other conditions associated with nerve pain.
Testing for Ilioinguinal Neuralgia
If you’re experiencing a burning, stabbing pain and a lack of feeling along the pathway of the ilioinguinal nerve (a nerve that runs through your lower abdomen), it could be a sign of ilioinguinal neuralgia. This is a condition where this specific nerve becomes irritated or compressed. The doctor can often discern if this is the cause of your symptoms by applying a local anesthetic (a numbing medicine) to the area where the ilioinguinal nerve is located. If the pain goes away after the anesthetic is applied, it often indicates ilioinguinal neuralgia.
However, just because an anesthetic doesn’t immediately alleviate symptoms, that doesn’t necessarily rule out ilioinguinal neuralgia. Sometimes, negative effects like inflammation or scarring from mesh-related surgeries can interfere with the anesthetic’s effectiveness.
To further understand your symptoms, doctors might use a few different evaluation methods:
1. A local anesthetic trial: The doctor injects a numbing agent in the area of the ilioinguinal nerve. If the pain subsides, it can confirm the diagnosis of ilioinguinal neuralgia.
2. Electrophysiologic studies: These are tests that measure electrical activity in your nerves. While they aren’t super reliable for diagnosing ilioinguinal nerve injury, they can help rule out other potential issues like problems with the nerves in your spine or around it.
3. Magnetic resonance imaging (MRI): This is a type of scan that creates detailed images of the inside of your body. An MRI on the lumbosacral spine (lower part of the back) can help exclude lumbar radiculopathies. These are conditions that affect the nerve roots in the spine and can also cause symptoms similar to ilioinguinal neuralgia.
4. Ultrasound imaging: This is a real-time imaging method that uses sound waves to create images inside the body. While it can be difficult to trace the nerve from its origin, it’s usually easier starting from the iliac crest (a prominent aspect of the hip bone) down to the external inguinal ring (an area in the lower abdomen). This can help identify the cause of the problem, such as scarring from previous surgery. A successful nerve block performed using ultrasound as guidance can also confirm the diagnosis of ilioinguinal neuralgia.
Treatment Options for Ilioinguinal Neuralgia
If you’re dealing with ongoing burning or stabbing pain in your groin area, it might be due to a condition called chronic neuropathic groin pain. This type of pain happens when a particular nerve in the groin area, called the ilioinguinal nerve, isn’t working properly. While this nerve pain might clear up on its own over time, in some cases the pain persists and interferes with daily activities.
Here are some ways that doctors usually treat this pain:
Conservative Treatment:
Doctors usually recommend starting off with simple, noninvasive treatments. If the pain subsides with time, they might watch and wait without any active treatment. They may also suggest changes to your daily activities, such as avoiding certain actions that seem to trigger the pain. For instance, you might notice that prolonged walking, bending over, or stretching your hip joint too much causes the pain to flare up. On the other hand, lying down with your hip and thigh bent may help to ease your symptoms.
Doctors often prescribe medications like nonsteroidal anti-inflammatory drugs (NSAIDs), opioids, antiepileptics, and antidepressants for pain relief. Exercises involving low-level electric nerve stimulation, release of muscle tension, and acupuncture might be helpful as well. However, if there’s no improvement after about 6 months, they might refer you to a pain specialist to discuss other treatments.
Ultrasound-Guided Nerve Block:
Another treatment often used is a nerve block – an injection of pain-reducing medication close to the problematic nerve. However, research results about the effectiveness of nerve blocks are mixed. While some studies suggest they can help a majority of patients, other research indicates very little to no pain relief from this therapy. But despite the different views, nerve blocks continue to be central to the treatment of chronic neuropathic groin pain.
Microwave Radiofrequency Nerve Ablation:
In this procedure, doctors use microwave radiofrequency energy to ablate, or burn, the nerve to minimize the pain. Some studies show that this treatment might provide longer-lasting pain relief compared to a nerve block.
Surgical Neurectomy:
If no other treatments are working or are available, doctors might consider neurectomy surgery, which is the surgical removal of the problematic nerve. This is usually the last option considered after all other treatments have failed. Although scarring and mesh implants can make it difficult to locate and remove the nerve, the surgery is generally effective for patients who have exhausted all other treatments. That said, some patients do report that their pain returns over time.
Additional Treaties:
There are several other treatments like cryotherapy (freezing the nerve), dorsal root ganglion stimulation, peripheral nerve stimulation, pulse radiofrequency ablation, and selective nerve root blocks which can be considered, but more research is needed to understand their long-term effectiveness and potential side effects.
If you’re experiencing ongoing groin pain, it’s best to seek medical advice right away. Your healthcare provider can work with you to find a treatment that best suits your symptoms and lifestyle.
What else can Ilioinguinal Neuralgia be?
When trying to diagnose the exact reason behind pain in the lower abdomen and groin, doctors consider several potential causes. These include:
- Femoral nerve neuralgia: This condition can lead to groin pain, which is often minimized when the hip is flexed and externally rotated. Common symptoms include unusual feelings in the leg and thigh, difficulty walking, and feeling like the knees are buckling. If the saphenous nerve in the thigh gets affected, it may cause numbness and knee pain.
- Genitofemoral nerve neuralgia: This typically results in a diminished sensation in the upper front thigh, below the groin. Symptoms often get worse with light touch, hip rotation, and extensive walking.
- Iliohypogastric nerve neuralgia: Usually starts after an abdominal surgery, causing a sharp, burning pain that extends from the surgery site into the upper groin area. The pain might also spread to the testicles or groin. This pain can start immediately after surgery or may show up months or even years later due to scar tissue formation.
- Lateral femoral cutaneous nerve neuralgia: Common symptoms include burning or tingling feeling on the front and side areas of the thigh, numbness, and symptoms getting worse when standing, walking, or straightening the hip. Symptoms may also show up when lying face down but sitting up usually provides relief.
- Lumbar plexopathy
- Lumbar radiculopathy
- Saphenous nerve neuralgia
- Varicocele
- Herpes Zoster
- Hydrocele
- Inguinal hernia
To be sure about the cause of the pain, doctors would take a detailed medical history and carry out several tests such as physical examination, electrophysiologic studies, ultrasound examination, and magnetic resonance imaging. They might also block individual nerves to further pinpoint the source of the pain.
What to expect with Ilioinguinal Neuralgia
It’s not unusual for people to experience long-term pain after an injury or entrapment of the ilioinguinal nerve, a major nerve found in the lower abdomen. Thankfully, most patients get better on their own or find relief through procedures like nerve blocks or surgical removal of the nerve.
However, some patients may continue to experience a severe burning pain for months or even years. This pain might not respond to usual pain-relief medicines. If this is the case, these patients may need to be seen by a pain specialist who can provide treatment through nerve blocks or surgery.
Possible Complications When Diagnosed with Ilioinguinal Neuralgia
Ilioinguinal blocks, which involve a small injection, significantly reduce the risk of toxicity from local anesthetics. Using ultrasound to guide this process further decreases the chance of complications. However, one common issue with these treatments is that they may not successfully alleviate symptoms.
Potential side effects of non-steroidal anti-inflammatory drugs include:
- Stomach inflammation
- Stomach ulcers
- Kidney damage
- Liver toxicity
- High blood pressure
- Bleeding or blood clots
Central painkillers, like gabapentin, may cause:
- Loss of coordination
- Dizziness
- Fatigue
- Fever
- Rapid involuntary eye movements
- Swelling in the extremities
- Sleepiness
Meanwhile, nerve blocks could lead to:
- Internal or surface bleeding resulting in hematomas (bruising)
- Bowel perforation
- Infection
- Damage to the nerves or blood vessels
- Pelvic hematomas
- Temporary pain where the injection was given
- Temporary numbness in the legs
Finally, complications from a neurectomy (nerve removal surgery) may include:
- Bruising caused by internal bleeding (hematoma)
- Infection
- Fluid-filled swelling (seroma)
- Swelling in the testicles
- Tingling sensations
Preventing Ilioinguinal Neuralgia
When dealing with ilioinguinal neuralgia, a painful condition affecting a nerve in the lower abdomen, it is important to discuss several factors with your doctor.
First, consider working on reducing your body weight. This may help reduce pressure on the nerve and lessen the pain.
Second, try to avoid certain positions and activities that trigger the pain. By identifying what actions lead to discomfort, you can start avoiding them to better manage your condition.
Lastly, maintaining a healthy diet is key. Good nutrition helps the body heal and function properly and may lessen the discomfort associated with this condition.
