Meralgia paresthetica(MP) is a result of entrapment of the lateral femoral cutaneous nerve (LFCN) which causes tingling or burning sensation in the lateral part of the proximal thigh. MP may be caused by compression of the anterior superior iliac spine(ASIS) area externally, by natural or traumatic thickening of inguinal ligament, by weight gain, or rarely by compression on the fascia lata. The author experienced a case of LFCN compression caused by circumflex iliac artery under inguinal ligament in a 24-year-old woman. On a plain radiography, ASIS abnormality or vertebral abnormality was not found, but MRI showed that the enhancement of vessel was in the LFCN pathway in the left ASIS medial part. Conservative treatment for 3 weeks showed no symptom improvement and surgical treatment was decided. The LFCN was released by bisecting the inguinal ligament longitudinally. It was found that circumflex iliac artery was engorged under the inguinal ligament and cauterization of this blood vessel was performed. Tingling pain in the lateral part of the thigh was lost immediately after surgery, and sensory deterioration improved at 2 months postoperatively
