What Is Meralgia Paresthetica?
Meralgia paresthetica is a condition that causes tingling, numbness, or a burning sensation in the outer thigh. Bernhardt-Roth syndrome is another name for it. It occurs when one of the leg's nerves, notably the lateral femoral cutaneous nerve, which supplies the front portion and side of the thigh, is subjected to excessive pressure or injury.
What Causes Meralgia Paresthetica?
The majority of cases of meralgia paresthetica have no known cause. The lateral femoral cutaneous nerve becomes trapped in meralgia paresthetica, usually under the inguinal ligament, which runs along the groin from the abdomen to the upper thigh. Any condition that raises pressure on the groin is a common source of this compression. Situations or conditions which can cause compression include:
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A car collision results in a seat belt injury.
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Belts, corsets, and tight pants are examples of restrictive apparel which could lead to compression on the nerve.
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A variety of sports and physical activities, such as gymnastics, baseball, soccer, bodybuilding, and vigorous exercise.
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Lying down in a curled-up position for long periods of time.
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Obesity or weight gain.
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Increased abdominal pressure due to fluid accumulation in the abdomen.
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Medical or surgical procedures and treatments, such as keyhole (laparoscopic) hernia repair.
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Nerve injury caused by diabetes.
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An injury or previous operation leads to scar tissue development near the inguinal ligament.
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Non-cancerous (benign) growths or tumors on a nerve are known as neuromas. Tumors in the pelvis or the abdomen can potentially compress the nerve.
What Are the Symptoms of Meralgia Paresthetica?
Many individuals with meralgia paresthetica experience the following symptoms:
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Numbness and tingling.
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Pain on the outside region of the thigh that may extend to the outside of the knee.
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Burning sensation.
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Reduced sensation.
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Even a light touch to the thigh can cause increased sensitivity, and the discomfort becomes worse.
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Pain gets worse after long durations of walking or standing.
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These symptoms usually affect one side of the body and may become more severe after walking or standing.
How Is Meralgia Paresthetica Diagnosed?
A diagnosis of meralgia paresthetica may usually be made based on the patient’s medical history, and a complete physical examination will be conducted. The doctor will inquire about the belts and clothing the patient uses at work and at other times of the day. The doctor will also inquire about lead exposure and alcohol consumption. The medical professional may conduct a hands-on test known as a pelvic compression test and ask the patient to describe the pain while tracing the painful or numb area on the thigh, as well as a test for sensation in the affected thigh.
Additional testing, such as strength and reflex tests, may be performed to rule out other possible explanations for the symptoms. The doctor may advise the patient to conduct the following diagnostic procedures to rule out other problems, such as femoral neuropathy or a problem associated with nerve root:
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Imaging Techniques: An X-ray to rule out other medical disorders such as bone cancers or a tumor of the pelvis and thigh maybe done since the X-rays of the hip and pelvic area will not show any specific alterations caused by meralgia paresthetica. Other imaging tests, such as computerized tomography (CT) scan or magnetic resonance imaging (MRI), may be requested to rule out other spinal or nerve disorders, such as a herniated disc. Uterine fibroids, which are non-cancerous growths in the uterus, can be ruled out using a pelvic ultrasound in a woman of childbearing age.
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Nerve Conduction Study Test: This involves a moderate electrical impulse used to activate the nerve using patch-style electrodes. Electrodes are placed along the lateral femoral cutaneous nerve (LFCN) to measure electrical impulses. These electrodes track how quickly the nerve sends impulses to the muscles around it. A comparison of each side's lateral femoral cutaneous nerve is possible using this test. This test may be performed primarily to rule out other possible reasons for the symptoms.
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Electromyography Test: It evaluates and diagnoses muscle and nerve problems by measuring the electrical discharges produced in muscles. A very small needle electrode is placed into the muscle and used to measure the electrical activity in the muscles. Although the results of this test are normal in meralgia paresthetica, it may be necessary to rule out other illnesses when the diagnosis is unclear.
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Anesthetic Injections: Nerve blockade is an anesthetic injection guided by ultrasound imaging at the place where the lateral femoral cutaneous nerve (LFCN) is most likely to be compressed or the area in the thigh where the lateral femoral cutaneous nerve (LCFN) enters. The discomfort will go away briefly if meralgia paresthetica is present.
Vitamin B levels, thyroid hormone levels, lead levels, and symptoms of anemia and diabetes may all be checked with blood tests ordered by the doctor.
How to Treat Meralgia Paresthetica?
The treatment's purpose is to relieve the pressure on the nerve. The type of treatment patients receive is determined by the source of their illness.
1) Physical Therapy: Stretching and strength exercises for the leg muscles or abs can be done with the help of a physical therapist. They might also attempt transcutaneous electrical nerve stimulation (TENS), which uses electrical impulses delivered through pads that are applied to the skin to block pain, or phonophoresis, which utilizes ultrasound to help the body absorb medicine via the skin.
2) Medications: If the symptoms last longer than two months or the pain is severe, patients may need to seek treatment which includes:
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Corticosteroid injections can help to decrease inflammation and relieve pain temporarily. Joint infection, nerve damage, discomfort, and skin whitening surrounding the injection site are all possible side effects.
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Anti-seizure drugs such as Pregabalin, Phenytoin, or Gabapentin may help alleviate the unpleasant sensation felt. Constipation, nausea, dizziness, drowsiness, and lightheadedness are some of the side effects.
- Tricyclic antidepressants may help one feel better. Drowsiness, dry mouth, constipation, and reduced sexual function are all possible side effects.
3) Surgery: Surgical intervention is only required in rare cases to relieve compression on the lateral femoral cutaneous nerve. Surgery is usually only recommended when other therapies have failed to relieve symptoms.
4) Lifestyle Modifications: The majority of cases improve with conservative treatments aimed at relieving nerve pressure, such as :
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Wearing loose-fitting clothes.
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Overweight or obese individuals are advised to lose weight.
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Including muscle strengthening and stretching exercises in daily routine.
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Take over-the-counter pain medicines such as Acetaminophen, Ibuprofen, or Aspirin.
Conclusion:
If one has meralgia paresthetica, they should avoid wearing tight clothing that presses on their upper thigh or hip areas, such as belts or corsets. If the nerve compression has a serious underlying cause, which is uncommon, the prognosis will be determined by the underlying cause. The prognosis is generally favorable. The pain usually goes away with time, although numbness and altered sensations can often last a long period.
