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Lasting effects of atlanto-axial manipulation on edge light pupil cycle time

By Adam Olarenshaw


Background: Edge Light Pupil Cycle Time (ELPCT) is a light reflex of the eye, which is controlled via the automatic nervous system. Studies have shown ELPCT to be a measurable constant, unaffected by visual acuity, refractive error, eye colour, pupil size or gender. Recent studies have shown that high-velocity manipulation of the upper cervical spine causes an immediate decrease in ELPCT on the same side as the manipulation. This change is presumed to me mediated in part by alterations in the autonomic tone following mauipulative intervention, therefore suggesting that unilateral manipulation produces an immdeiate unilateral change in the autonomic nervous system. Objective: To investigate the lasting effects (up to 1 hour) of C1-2 high velocity low amplitude manipulation upon ELPCT. Design: A two group blind, randomized study, with a control group. Conclusion: This suggests that ELPCT, which is mediated by the autonomic nervous system, can be directly influenced by high-velocity manipulation to the atlanto-axial joint and these changes occur on the same side as the manipulation (i.e. unilateral manipulation produces unilateral physiological change). Over a one-hour time frame these changes are still significant at 20-minutes post-manipulation but only slightly evident at one-hour post manipulation. This minor thesis was written by a post-graduate student as part of the requirements of the Master of Health Science (Osteopathy) program

Topics: 320000 Medical and Health Sciences, Centre for Ageing, Rehabilitation, Exercise & Sport Science (CARES), School of Sport and Exercise Science, Edge Light Pupil Cycle Time (ELPCT), manipulation (Therapeutics), eye, autonomic nervous system, Osteopathy Masters Projects
Year: 2004
OAI identifier:

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