Hyperostosis (lipping) due to costovertebral arthritis was found frequently (84.3%) impinging on the sympathetic trunks (ganglia and cord), rami communicantes and roots of the splanchnic nerves on both sides of the spine in more than 1,000 dissecting room cadavers examined and 34 cadavers of adult and elderly people specially dissected. As a result of the compression, the affected sympathetic structures were angulated, deflected from their course, enlarged and often infiltrated with connective tissue. The possible symptoms which may result from this kind of compression are discussed.