The purpose of the study is to highlight that prolonged blocks with spinal anesthesia are not usually due to neurologic defects. Consent for data publication was obtained. A 35-year-old female patient with right upper tibial chondrosarcoma was planned to undergo excision and reconstruction with a free vascularized fibular graft. The patient had no significant medical history. We gave spinal anesthesia, which is to be continued with general anesthesia after regression of the sensory level. After 3 hours, we evaluated the patient for the second time to find sensory block at T10 level. It was decided to carry out these evaluations hourly and wait for general anesthesia. Ten hours after the spinal anesthesia, the sensory block was still at T10 level. After 13 hours, the surgical procedure was finished, and the sensory block was still at T10 level and the motor block according to the Bromage scale remained at grade 4. A computed tomography was performed and did not reveal signs of spinal compression, spinal canal stenosis, or other anomalies (magnetic resonance imaging was unavailable). A complete motor and sensory recovery from the spinal block was observed 20 hours after spinal anesthesia. We present a case of major microscopic surgery done over 13 hours with a single shot of spinal anesthesia in a 35-year-old female patient. Complete recovery of sensory and motor blocks has been after 20 hours. We also review other cases of unusually prolonged spinal blocks and the possible differential diagnosis for that.

Keywords
Prolonged anesthesia; Prolonged block; Spinal block; Spinal anesthesia; Regional anesthesia; Dexamethasone