Is cervical spine rotation, as used in the standard vertebrobasilar insufficiency test, associated with a measureable change in intracranial vertebral artery blood flow?

Influence of osteopathic manipulation on blood flow velocity of the cerebral circulation in chronic mechanical neck pain

“…24,25 or significant oscillations in blood flow velocity of the studied population. It is possible to state that OM-CRAT in sliding and rotation has not posed risk to the circulation of such arteries and, according to some literature statements, osteopathic manipulative treatment or vertebral manipulation has not caused injury or undue tension on vertebral and carotid arteries 12,13,[20][21][22] , providing significantly lower sliding than that of clinical tests for VBI 9,10,13,20 . So, cervical manipulation performed by a professional was not in this study a risk factor for vertebrobasilar and carotid injury 12,13,[20][21][22][23] .…”

“…In case of vertebrobasilar insufficiency (VBI), clinical tests envolve cervical extension associated to rotation above 45 or 50º, which compress vertebral artery. During these tests, there may be typical symptoms such as dizziness or vertigo, visual disorders, nystagmus or even fainting, but seldom they cause stroke or death [9][10][11][12][13] . However, such signs and symptoms may also suggest benign paroxysmal positional vertigo and not VBI 14 .…”

Manual Therapy and Cervical Arterial Dysfunction, Directions for the Future: A Clinical Perspective

“…Some fl ow studies have insonated the vessel as it enters the lower part of the vertebral column (the pre-transverse level) 22,[76][77][78][79][80] . Few studies have measured blood fl ow in the intracranial VA 21,23,24,28 where it may be argued that VA blood fl ow related to the upper cervical spine would be a more accurate measure of fl ow change 24,32,73,74 . It has also been shown that VA atherosclerotic plaques do exist throughout the course of the VA 64 .…”

The effect of end-range cervical rotation on vertebral and internal carotid arterial blood flow and cerebral inflow: A sub analysis of an MRI study

“…In three cases (Figure 4c), blood flow volume decreased in all four individual arteries on rotation, to produce a large cumulative decrease in TCI of up to 3.9 mL/sec (42.6%) compared to neutral. (Haynes, 1996;Rivett et al, 1999;Mitchell, 2003;Sakaguchi et al, 2003;Mitchell et al, 2004) Total cerebral inflow generally appears to be unaffected by end-range cervical rotation. Although total flow decreased slightly with rotation, the changes were very small and did not approach statistical significance.…”

“…Attempts to quantify blood flow changes in the VAs on neck rotation, with the premise that large changes in flow might indicate greater biomechanical stress on the artery, have yielded conflicting findings. Some studies showing reduced flow on contralateral rotation, some with ipsilateral and others no change in either direction, sometimes despite positive VBI tests (Thiel, Wallace et al 1994, Haynes 1996, Rivett, Sharples et al 1999, Haynes and Milne 2001 Sakaguchi, Kitagawa et al 2003, Zaina, Grant et al 2003, Mitchell, Keene et al 2004, Sultan, Hartshorne et al 2009, Bowler, Shamley et al 2011, Quesnele, Triano et al 2014. Of the few studies that have examined blood flow in the ICAs, similarly conflicting findings have emerged (Sultan, Hartshorne et al 2009, Bowler, Shamley et al 2011.…”