Case presentation   A 24-year-old woman suddenly fell to the ground without any loss of consciousness and rushed to her family doctor due to complete paralysis of her left leg. She has no other neurological symptoms and is otherwise healthy. She has no relevant past or family history and has never smoked or drunk alcohol. Examination She looks well and is in no distress. The only abnormalities are in the nervous system.

She is completely oriented, and the Mini-Mental State score is normal. The cranial nerves and the neurology of the upper limbs and right leg are normal. The left leg is completely still during the examination, and the patient cannot move it on request. The tone is normal; however, coordination could not be tested because of the paralysis. The superficial sensation was completely absent below the margin of the left buttock and the left groin, with a clear transition to…