Anatomic variability of the lateral femoral cutaneous nerve: Value of 3T MRI in identifying anomaly for surgical intervention

The anatomic variability of the lateral femoral cutaneous nerve (LFC) creates diagnostic as well as therapeutic problems. A case is reported in which a woman with complaints of pain in the anterior and lateral thigh was referred for evaluation. Symptoms arose after an abdominal hysterectomy. Her symptoms were the territory of the LFC and not of the L2/L3 dermatome. She had a Tinel sign that was positive for the LFC skin territory, but this was located over the anterior superior iliac spine (ASIS), instead of medial to it. For this reason, a 3-Tesla MR neurography imaging was obtained. This showed the LFC as crossing over the ASIS, instead of being located either within or beneath the inguinal ligament. MRI imaging facilitated successful surgical treatment. This is the first report of the MR neurography and intraoperative appearance of this least common anatomic course for the LFC.