Percutaneously inserted central venous lines are usually a safe and effective means of securing prolonged central venous access but can have serious complications. One patient who experienced clinically important morbidity related to inadvertent malpositioning of a central venous catheter is described. It was inserted via the left saphenous vein into the lumbar venous plexus and resulted in milky cerebrospinal fluid, urine retention, and paraplegia. Reviewing the literature, only 11 patients with the same malposition were reported, three of them with percutaneously inserted central venous lines. In these three patients and our patient the left saphenous vein was used. Neurologic sequelae of paraplegia and urine retention were recorded in 25% (3/12) of patients. The mortality rate approached 42% (5/12) but only two patients were related to catheter misplacement. Although the complication rate is extremely low and difficult to recognize, catheter malposition into the ascending lumbar vein can lead to lethal complications.