Cervical manipulation (neck adjustments) appears a crude or even barbaric practice. Many medical practitioners allege that it is unsafe and can cause strokes. It's commonly known to be an effective treatment, but is it safe?
Thankfully we have decades of high quality research to scrutinize this question and the results will undoubtedly surprise you. To my knowledge, we will be the first to scour this information and provide a digestible overview to the public.

Citations.

               Symons BP, Leonard T, Herzog W. Internal forces sustained by the vertebral artery during spinal manipulative therapy. J Manipulative Physiol Ther. 2002 Oct;25(8):504-10. doi: 10.1067/mmt.2002.127076. PMID: 12381972. 
               Moser N, Mior S, Noseworthy M, Côté P, Wells G, Behr M, Triano J. Effect of cervical manipulation on vertebral artery and cerebral haemodynamics in patients with chronic neck pain: a crossover randomised controlled trial. BMJ Open. 2019 May 28;9(5):e025219. doi: 10.1136/bmjopen-2018-025219. PMID: 31142519; PMCID: PMC6549698.
               Cassidy JD, Boyle E, Côté P, He Y, Hogg-Johnson S, Silver FL, Bondy SJ. Risk of vertebrobasilar stroke and chiropractic care: results of a population-based case-control and case-crossover study. J Manipulative Physiol Ther. 2009 Feb;32(2 Suppl):S201-8. doi: 10.1016/j.jmpt.2008.11.020. PMID: 19251066.
                 Haldeman S, Kohlbeck FJ, McGregor M. Risk factors and precipitating neck movements causing vertebrobasilar artery dissection after cervical trauma and spinal manipulation. Spine (Phila Pa 1976). 1999 Apr 15;24(8):785-94. doi: 10.1097/00007632-199904150-00010. PMID: 10222530. 
                   Smith WS, Johnston SC, Skalabrin EJ, Weaver M, Azari P, Albers GW, Gress DR. Spinal manipulative therapy is an independent risk factor for vertebral artery dissection. Neurology. 2003 May 13;60(9):1424-8. doi: 10.1212/01.wnl.0000063305.61050.e6. PMID: 12743225. 
                     Kosloff TM, Elton D, Tao J, Bannister WM. Chiropractic care and the risk of vertebrobasilar stroke: results of a case-control study in U.S. commercial and Medicare Advantage populations. Chiropr Man Therap. 2015 Jun 16;23:19. doi: 10.1186/s12998-015-0063-x. PMID: 26085925; PMCID: PMC4470078.
                      Fries JF: Assessing and understanding patient risk, Scand J Rheumatol 92(suppl):21, 1992.
                       Dabbs V, Lauretti WJ: A risk of assessment of cervical manipulation vs. NSAIDs for the treatment of neck pain,  JMPT 18:530, 1995.