Meralgia paresthetica occurs when the lateral femoral cutaneous nerve â which supplies sensation to the surface of your outer thigh â becomes compressed, or pinched. The lateral femoral cutaneous nerve is purely a sensory nerve and doesn't affect 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 â often under the inguinal ligament, which runs along your groin from your abdomen to your 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
- Scar tissue near the inguinal ligament due to injury or past surgery
Nerve injury, which can be due to diabetes or seat belt injury after a motor vehicle accident, for example, also can cause meralgia paresthetica.