Surgery of thoracoabdominal aneurysms is accompanied by many complications of which spinal cord damage is the most serious. Such a complication tends to be the subject of litigation and medicolegal assessment. This report presents a risk control concept focussed on the reduction of spinal cord damage after surgery for a thoracoabdominal aneurysm. This concept may provide a basis for a risk management program in major surgery. Apart from sparing the patient a serious complication, improvement of the quality of care and anticipation of a medicolegal assessment were considered valuable benefits of such an effort. It is described how the threat of litigation--also in Europe--may affect clinical practice. A definition of surgical failure is described related to the five elements of risk homeostasis: complexity, linkage, cascade, human factor and safety margins. Limitations of risk control in the surgery of thoracoabdominal aneurysms are described. Finally the role of perception of risks by patient and doctor as well as the importance of informed consent and adequate disclosure are described in respect of medical quality improvement and litigation.