Meralgia paresthetica

Overview

Meralgia paresthetica is a condition that causes tingling, numbness and burning pain in the outer thigh. It's caused by compression of the nerve that provides feeling to the skin covering the thigh. Meralgia paresthetica also is known as lateral femoral cutaneous nerve entrapment.

Tight clothing, obesity or weight gain, and pregnancy are common causes of meralgia paresthetica. But meralgia paresthetica also can be due to an injury or a disease such as diabetes.

Meralgia paresthetica often can be relieved with conservative measures, including wearing looser clothing. If symptoms aren't relieved by those measures, treatment may include medicines. Rarely, surgery is needed.

Symptoms

Meralgia paresthetica may cause these symptoms in the outer part of the thigh:

• Tingling.
• Burning pain.
• Decreased feeling or numbness.
• Increased sensitivity and pain to even a light touch.

These symptoms commonly occur on one side of your body and might intensify after walking or standing.

When to see your doctor

See your healthcare professional if you have symptoms of meralgia paresthetica.

Causes

Meralgia paresthetica occurs when the lateral femoral cutaneous nerve is pinched, also known as compression. The nerve supplies feeling to the surface of the outer thigh. The nerve only affects sensation and doesn't impact your ability to use your leg muscles.

In most people, this nerve passes through the groin to the upper thigh without trouble. But in meralgia paresthetica, the lateral femoral cutaneous nerve becomes trapped. Often the inguinal ligament pinches the nerve. This ligament runs along the groin from the stomach to the upper thigh.

Common causes of this compression include any condition that increases pressure on the groin, including:

• Tight clothing, such as belts, corsets and tight pants.
• Obesity or weight gain.
• Wearing a heavy tool belt.
• Pregnancy.
• Fluid accumulation in the abdomen causing increased abdominal pressure.
• Scar tissue near the inguinal ligament due to injury or past surgery.

Nerve injury also can cause meralgia paresthetica. Nerve injury can be due to diabetes, trauma after surgery or seat belt injury after a motor vehicle accident.

Risk factors

The following might increase your risk of meralgia paresthetica:

• Extra weight. Being overweight or obese can increase the pressure on your lateral femoral cutaneous nerve.
• Pregnancy. A growing belly puts added pressure on your groin, through which the lateral femoral cutaneous nerve passes.
• Diabetes. Diabetes-related nerve injury can lead to meralgia paresthetica.
• Age. People between ages 30 and 60 are at a higher risk.

Diagnosis

Your healthcare professional can make a diagnosis of meralgia paresthetica based on your medical history and a physical exam. You may need a test to check the feeling in your thigh. Your healthcare professionals also may ask you to describe the pain and to trace the numb or painful area on your thigh.

Other exams may include strength testing and reflex testing to help exclude other causes of your symptoms.

Tests also may look for an issue with the nerve root or damage to the femoral nerve, known as neuropathy. Your healthcare professional might recommend:

• Imaging studies. Changes related to meralgia paresthetica won't appear on X-ray. But images of your hip and pelvic area might be helpful to exclude other conditions as a cause of your symptoms.

  A CT scan or MRI might be ordered if your healthcare professional suspects that a tumor could be causing your symptoms.

• Electromyography. This test measures the electrical discharges produced in muscles to help evaluate and diagnose muscle and nerve conditions. A thin needle called an electrode is placed into the muscle to record electrical activity. This test might be needed to exclude other disorders.
• Nerve conduction study. Patch-style electrodes are placed on your skin to stimulate the nerve with a mild electrical impulse. The electrical impulse helps diagnose damaged nerves. A comparison of the lateral femoral cutaneous nerve on each side may be performed. This test might be done primarily to exclude other causes for the symptoms.
• Nerve block. Pain relief achieved from anesthetic injection into your thigh where the lateral femoral cutaneous nerve enters into it can confirm that you have meralgia paresthetica. Ultrasound imaging might be used to guide the needle.

Treatment

For most people, the symptoms of meralgia paresthetica ease in a few months. Treatment focuses on relieving nerve compression.

Conservative measures

Conservative measures include:

• Wearing looser clothing.
• Losing excess weight.
• Taking pain relievers available without a prescription. They might include acetaminophen (Tylenol, others), ibuprofen (Advil, Motrin IB, others) or aspirin.

Medications

If symptoms last for more than two months or if your pain doesn't go away with conservative measures, treatment might include:

• Corticosteroid injections. Injections can reduce inflammation and relieve pain for a short time. Possible side effects include joint infection, nerve damage, pain and lightening of skin around the injection site.
• Tricyclic antidepressants. These medicines might relieve your pain. Side effects include drowsiness, dry mouth, constipation and impaired sexual functioning.
• Gabapentin (Gralise, Neurontin), phenytoin (Dilantin, Phenytek) or pregabalin (Lyrica). These anti-seizure medicines might help lessen pain. Side effects include constipation, nausea, dizziness, drowsiness and lightheadedness.

Surgery

Rarely, surgery to decompress the nerve may be considered. This option is only for people with very painful and long-lasting symptoms.

Preparing for an appointment

Here's some information to help you get ready for your appointment.

What you can do

Make a list of:

• Your symptoms, including any that may seem unrelated to the reason for which you scheduled the appointment, and when they began.
• Key personal information, including medical conditions and major stresses or recent life changes.
• All medicines, vitamins or supplements you take, including doses.
• Questions to ask your healthcare professional.

For meralgia paresthetica, basic questions to ask include:

• What is likely causing my symptoms?
• What tests do I need?
• Is my condition likely temporary or chronic?
• What is the best course of action?
• What are the alternatives to the primary approach you're suggesting?
• I have other health conditions. How can I best manage them together?
• Are there restrictions I need to follow?
• Should I see a specialist?

Don't hesitate to ask any other questions.

What to expect from your doctor

Your healthcare professional may have question that include:

• What part of your leg is affected?
• Have you had recent surgeries?
• Have you had recent injuries to your hip area, such as from a seat belt in a motor vehicle accident?
• Do you regularly do repetitive activities that affect your hip area, such as cycling?
• Have you gained weight?
• Have you recently been pregnant?
• Do you have diabetes?
• Is the burning or tingling occasional or continuous?
• How bad is your discomfort?
• Are there activities that worsen your symptoms?
• Is there weakness in your leg?

What you can do in the meantime

If your pain is bothersome, pain relievers such as acetaminophen (Tylenol, others), ibuprofen (Advil, Motrin IB, others) or aspirin may be helpful. Also, avoid tight clothing.