Despite modern diagnostic imaging options pyogenic infections of the spine are often detected tardily and therefore accompanied by a high mortality rate. To ensure an efficient and adequate therapy it is necessary to identify and treat the focus of inflammation. The recommendations for the operative strategy are still a highly controversial issue. On the other hand no classification and guidelines for surgical treatment and treatment strategies of pyogenic spinal infection have yet been published.Pyogenic spinal infections are often underestimated in frequency of occurrence and severity of symptoms. From 1994 until 2008, 269 patients suffering from an infection of the thoracic and lumbar spine were treated in the Department of Orthopedic Surgery Heidelberg and 221 patients underwent surgery. Within the scope of a clinical trial clinical aspects and therapeutic consequences of patients with pyogenic spinal infections were retrospectively investigated. Based on the study data a classification of pyogenic spinal infections of the thoracic and lumbar spine and a guide for surgical decision-making was developed.