Does case misclassification threaten the validity of studies investigating the relationship between neck manipulation and vertebral artery dissection stroke? Yes

Abstract

BackgroundFor patients and health care providers who are considering spinal manipulative therapy of the neck, it is crucial to establish if it is a trigger for cervical artery dissection and/or stroke, and if it is, the magnitude of the risk.DiscussionWe discuss the biological plausibility of how neck manipulation could cause cervical artery dissection. We also discuss how case misclassification threatens the validity of influential published studies that have investigated the relationship between neck manipulation and dissection. Our position is supported by the fact that the largest epidemiologic studies of neck manipulation safety with respect to neurological outcomes have relied on International Classification of Diseases-9 codes for case identification. However, the application of these codes in prior studies failed to identify dissections (rather than strokes in general) and so conclusions from those studies are invalid.ConclusionThere are several methodological challenges to understanding the association between neck manipulation and vertebral artery dissection. Addressing these issues is critical because even a modest association between neck manipulation and cervical artery dissection could translate into a significant number of avoidable dissections given the widespread use of neck manipulation by providers from various backgrounds. We believe that valid case classification, accurate measurement of manipulative procedures, and addressing reverse causation bias should be top priorities for future research.

Impulstechniken an der HWS

“…Paulus und Thaler [15] sehen in dieser Art der Argumentation zwar eine Möglichkeit der Erklärung, fragen aber, warum Patienten nach Besuchen bei Chiropraktikern auch vermehrt Dissektionen aufwiesen, obwohl sie nur zur Behandlung von LWS-Beschwerden oder zur "Maintenance" dort gewesen seien, demnach also nicht unter HWS-Beschwerden oder Kopfschmerzen gelitten hätten. Dabei stützen sich die Autoren allerdings nicht auf Statistiken aus Studien, sondern auf die eigene Erfahrung und die von Kollegen.…”

“…Paulus und Thaler[15] sehen allerdings ein Problem in der Klassifikation von Fällen, die als Grundlage der meisten Studien dienen. Da Dissektionen selten vorkommen, werden oftmals auch Patienten in Studien aufgenommen, die andere Ursachen für Schlaganfälle haben.…”