Reprinted with permission from the Authors (Aldis, C. K., Hill, J. M.) and the Royal Society of New South Wales, Journal and Proceedings, Volume 112, pp 93-99, 1979. Full text
Data from a chiropractor is studied with the view to obtaining a mathematical model of the alteration in the position of the atlas bone due to adjustment. The particular chiropractor believes that the patient's illness, for example low back pain, is primarily due to misalignments of the atlas bone, which he attempts to correct by applying a mechanically produced force. We find that there is considerable variation in the response of individual patients, indicating that a 'population' model is not applicable. In attempting to restore the atlas bone to its 'normal' position the chiropractor takes 'before' and 'after' X-rays, from which the displacements of the bone due to the applied force are measured. Statistically significant differences in before and after adjustment measurements are demonstrated both for the total sample and also when the sample is broken down into age, sex and adjustment type categories. It was found that there was not a transition from small misplacements of the atlas in the young to larger misplacements in the old.
This abstract is reproduced with the permission of the publisher. JMPT article only available in print.