Which nerve is associated with sensory loss on the lateral thigh when compressed (meralgia paresthetica)?

Which nerve is associated with sensory loss on the lateral thigh when compressed (meralgia paresthetica)?

• A. Obturator nerve
• B. Lateral femoral cutaneous nerve
• C. Femoral nerve
• D. Ilioinguinal nerve

Answer: (B)

Meralgia paresthetica occurs when the lateral femoral cutaneous nerve is compressed as it passes under the inguinal ligament near the anterior superior iliac spine. This nerve is responsible for sensation to the lateral aspect of the thigh, so compression produces numbness or burning/tingling in that area. Since the lateral femoral cutaneous nerve is purely sensory, motor function of the thigh is not affected. Other nerves would produce different patterns: the obturator nerve covers the medial thigh; the femoral nerve supplies the anterior thigh and part of the leg sensation with motor functions; the ilioinguinal nerve covers the groin and upper medial thigh.

Meralgia paresthetica occurs when the lateral femoral cutaneous nerve is compressed as it passes under the inguinal ligament near the anterior superior iliac spine. This nerve is responsible for sensation to the lateral aspect of the thigh, so compression produces numbness or burning/tingling in that area. Since the lateral femoral cutaneous nerve is purely sensory, motor function of the thigh is not affected. Other nerves would produce different patterns: the obturator nerve covers the medial thigh; the femoral nerve supplies the anterior thigh and part of the leg sensation with motor functions; the ilioinguinal nerve covers the groin and upper medial thigh.