A 73-year-old man with an extensive cardiovascular risk profile and history underwent a transurethral resection of the prostate under spinal anaesthesia. The use of acetylsalicylic acid was stopped 10 days before the operation. No anaesthesiological or surgical complications occurred during the operation, but 6 hours after the operation the patient developed severe pain in both legs. Besides the hyperalgesia, there was a paresis and a reduced sensitivity of the legs. The patient had developed anterior spinal artery syndrome due to ischaemia of the lower thoracic myelum. Despite intensive rehabilitation this ultimately resulted in a residual disability and the patient became wheelchair bound. There seems to be a correlation between the patient's comorbidity, the stopping of the thrombocyte aggregation inhibitor and the occurrence of this particularly rare complication.