With changes in vehicle formulation and in clinical practice, concern for toxicity again subsided, only to reemerge a decade later with reports of cauda equina syndrome associated with continuous spinal anesthesia (CSA). In contrast to the more common single-injection technique, CSA involves placing a catheter in the subarachnoid space to permit repetitive dosing to facilitate adequate anesthesia and maintenance of block for extended periods. In these cases, the local anesthetic was evidently administered to a relatively restricted area of the subarachnoid space; in order to extend the block to achieve adequate surgical anesthesia, multiple repetitive doses of anesthetic were then administered. By the time the block was adequate, neurotoxic concentrations had accumulated in a restricted area of the caudal region of the subarachnoid space. Most notably, the anesthetic involved in the majority of these cases was lidocaine, a drug most clinicians considered to be the least toxic of agents. This was followed by reports of neurotoxic injury occurring with lidocaine intended for epidural administration that had inadvertently been administered intrathecally, similar to the cases involving chloroprocaine a decade earlier. The occurrence of neurotoxic injury with CSA and subarachnoid administration of epidural doses of lidocaine served to establish vulnerability whenever excessive anesthetic was administered intrathecally, regardless of the specific anesthetic used. Of even more concern, subsequent reports provided evidence for injury with spinal lidocaine administered at the high end of the recommended clinical dosage, prompting recommendations for a reduction in maximum dose. These clinical reports (as well as concurrent experimental studies) served to dispel the concept that modern local anesthetics administered at clinically relevant doses and concentrations were incapable of inducing neurotoxic injury.