Subarachnoid block is a widely practiced anesthetic technique. With the availability of small-diameter needles and the rises in out-patient surgery, the number of procedures performed with subarachnoid block and short-term local anesthesia have increased. We report two cases of bilateral pain in the lower extremities appearing 20-24 h after intradural anesthesia with 2% hyperbaric lidocaine. We analyze the factors that might have triggered this complication and compare the two patients with 14 others described in the literature. Three points in common were found: the use of hyperbaric lidocaine, administration of the agent through small gauge needles and the performance of out-patient surgery.