Background: Meralgia paresthetica, a syndrome of pain and/or dysesthesia in the anterolateral thigh, is normally caused by an entrapment of the lateral femoral cutaneous nerve (LFCN) at the anterior superior iliac spine. In a few cases compression of the nerve in the retroperitoneum has been reported to mimic meralgia paresthetica.
Case description: A 67-year-old woman presented with a 5-year history of permanent paresthesia in the anterolateral thigh. Motor weakness was not detected. Electromyography showed a neurogenic lesion at the level of L3. Lumbar spine MRI detected a foraminal-extraforaminal disc herniation at L2/L3, which was extirpated via a lateral transmuscular approach. The patient was free of symptoms on the first postoperative day.
Conclusion: In patients with meralgia paresthetica we emphasize a complete radiological investigation of the lumbar spine, including MRI, to exclude radicular compression by a disc herniation or a tumour at the level of L2 or L3.