Principal Investigator:  Bernadette Murphy, D.C., Ph.D.
Research Site:  University of Auckland
Title: The Development of a Sensitive Technique to Measure Changes in Central Neural Processing of Somatosensory Input

Synopsis:

This research proposes to evaluate the potential use of somatosensory evoked potentials (SSEPs) in the study of somatosensory function. Its two objectives are to (i) develop the technique of measuring SSEP ratios elicited by the stimulation of two upper limb peripheral nerves both singly and by simultaneous dual peripheral nerve stimulation; and (ii) to carry out reliability studies to ensure that the various ratios obtained from dual peripheral nerve stimulation are consistent when measured on the same subjects several minutes and several weeks apart. Asymptomatic volunteers aged 18-50 are to be recruited from student and staff populations at the University.

With the long-range objective of determining the effects of spinal manipulation over time on SSEP, the characteristics (inherent stability/variability) of this measurement are critical.  Since one of the principal limitations of studies of somatosensory function is that they are typically subjective in nature, the validation of objective outcome measures in this study would be an important contribution to this field. Ultimately, validated measurements such as these would be expected to contribute to our understanding of the clinical neurophysiological effects of spinal manipulation.

Principal Investigator:   Anthony Lisi, D.C.
Research Site:  Private Practice
Title:   In-vivo Disc Manometry during Spinal Manipulation

Synopsis:

Does lumbar intradiscal pressure change in response to chiropractic spinal manipulation? An answer to this question will begin to emerge with this feasibility study involving three asymptomatic patients without significant spinal pathology, in which lumbar intradiscal pressure before, during, and after spinal manipulation is to be evaluated. Measurement is to be accomplished by means of pressure transducers inserted in the center of the disc, with spinal manipulation to be accomplished by means of a lumbar side-posture mamillary push.  The thrust is to be aimed at the L4-L5 spinal unit. Pressure measurements are to be taken from the transducers inserted in this region.

This study adds to the limited knowledge base regarding the mechanism of action of spinal manipulation in lumbar disc pathology. Some (but not all) previous studies have reported decreases in disc bulge size, but this neither predicts nor correlates with symptomatology. Previous studies have suggested that high-velocity, low amplitude manipulations may decrease lumbar intradiscal pressure in cadavers or in the porcine spine. This study is the first to employ live human subjects and is intended to improve treatment outcomes.

Principal Investigators:  Mike Baselice, Patricia Jackson
Research Sites:   American Chiropractic Association/Baselice and Associates/Lewin Group
Title:  Calculation of Chiropractic Practice Expenses as an Input for CMS Relative Value Units

Synopsis:

The purpose of this study (matched with funds from the ACA) is to review estimates currently used to derive the Chiropractic Manipulative Treatment [CMT] practice expenses for chiropractors. It seeks to do so by using a modification of the AMA Socioeconomic Monitoring Survey, establishing whether the resource-based practice expense relative value units currently assigned to the CMT codes by the Centers for Medicare and Medicaid are in fact valid.

This undertaking is in response to questions concerning the current practice expenses for chiropractors, now set at values similar to those for general internists despite the fact that preliminary surveys suggest that practice expenses for chiropractors could in fact be 16-20% higher. The proposed research is to be conducted by means of telephone interviews with a random sample of 3,000 field doctors who will complete worksheets that will answer questions regarding expenses based on the year 2000 taxes. The interviews, already scripted, are to be coded and entered into a spreadsheet. Afterwards, the data is to be forwarded to the Lewin Group for analysis before being forwarded directly to the Centers for Medicare and Medicaid.