Manipulative therapy of the cervical spine is associated with a considerable risk of stroke. We evaluated all cases with the diagnosis of arterial dissection submitted between 1996 and 2005 to the Schlichtungsstelle für Arzthaftpflichtfragen der Norddeutschen Arztekammern for assessment of the accusations brought against the therapists who conducted the manipulation. Neither in the 7 carotid nor in the 9 vertebral artery cases could a causal link be made between the dissection and the manipulation. However, in 5 of the 7 carotid and 7 of the 9 vertebral artery dissections there was clear evidence or high probability that the dissection was present prior to the manipulation, and had caused neck pain, segmental dysfunction and, in some cases, even neurological symptoms. Stroke after manipulative therapy was due to embolisation of thrombotic material from the dissected artery. As both cervical arterial dissection and cervical spine disorder usually cause similar signs and symptoms physicians must differentiate between these two entities prior to any manipulative therapy. Clinical indicators of pre-existent dissection and the medicolegal implications are discussed in this paper.