The authors present the technique of chemical lumbar sympathectomy by an anatomically new medial transdiscal approach. On a group of 80 operations they analyze the indication criteria, complications and results of this method. They compare the percutaneous technique of severing of the sympathetic nerve with the classical surgical approach. In 41 patients where a modified transdiscal approach was used the authors did not encounter any serious complications. Using thin needles (minimum 23-G) they recommend this method as an alternative of the classical approach of Kappis.