|
July 2004 Table of Contents
CBP Non-Profit Funds
International Biomechanical and Neurophysiological Research
- By Christopher J. Colloca, DC
- and Tony S. Keller, PhD
Dr. Christopher J. Colloca is a 1995 cum laude graduate of Life College
School of Chiropractic (Marietta, GA), and a 1990 graduate of Ithaca
College (Ithaca, NY). He directs a full time private practice and
clinical research facility in Phoenix, Arizona. Dr. Colloca holds
postgraduate faculty appointments in five chiropractic colleges and has
given hundreds of postgraduate educational seminars for thousands of
chiropractors around the world. He is a graduate student at Arizona
State University (Tempe, AZ) in the Department of Kinesiology studying
biomechanics. He has authored over 25 journal publications and over 20
conference proceedings. Dr. Colloca was a recipient of Sofamor Danek
Poster Presentation Award (2002 International Society for the Study of
the Lumbar Spine), and the 1st Prize Scott Haldeman Award (2003 World
Federation of Chiropractic).
Dr. Tony
S. Keller received his PhD in mechanical engineering from Vanderbilt
University in 1988. He is currently Professor and Interim Chair of
Mechanical Engineering at the University of Vermont. Dr. Keller has
received numerous awards, including the American Society of Biomechanics
Young Scientist Award (1987), International Society for the Study of the
Lumbar Spine Volvo Award in Experimental Studies (1990), Fulbright
Scholarship to conduct spine biomechanics research in Sweden (1992),
Mac-Nab-Larocca Research Fellowship to conduct spine clinical
biomechanics research (Belgium 1998), the Sofamor Danek Poster
Presentation Award (2002 International Society for the Study of the
Lumbar Spine), and the 1st Prize Scott Haldeman Award (2003 World
Federation of Chiropractic). He has authored over 65 journal
publications and over 120 conference proceedings.
At its annual board meeting last year, Chiropractic Biophysics® Non-profit, Inc.
approved funding for several biomechanical and neurophysiological investigations
that are currently taking place in collaboration with some of the foremost
research institutions around the World. The aims these investigations are
multifaceted and include understanding how the spine responds to different kinds
of forces and speeds that are used in everyday chiropractic adjustments and what
effect these different techniques have on bone movement, neurophysiological
reflex responses, and muscle inhibition. In addition, we are studying how
degeneration affects the spinal motion, spinal stiffness, and neuromuscular
system.
As chiropractic theories undergo increased
scrutiny, the necessity to design studies to investigate clinically relevant
questions increases. For the past eight years, we have been collaborating on
various chiropractic research projects and are thankful for the support of CBP®
Non-profit, Inc. and Dr. William Harris, who this year gave an additional
$10,000 to add to the $25-50,000/year he has donated in support of our research.
These studies have ranged from the development of chiropractic adjusting
instruments,1 spinal stiffness assessments,2-5 and quantifying bone
movement,6-10 neurophysiological,10-12 and neuromuscular13,14 responses from
chiropractic adjustments. Our collaboration with CBP® researchers has also
progressed with studies of spinal modeling.15,16 Currently, our research is
being conducted in the U.S., Belgium, Sweden, and Australia through
relationships with other physicians and scientists.
The extensive innervation of the
discoligamentous and muscular tissues of the spine inherently provides a
theoretical framework to study the mechanisms of chiropractic adjustments,
namely, how mechanical stimulation via chiropractic adjustment acts on the spine
and nervous system. How do chiropractic adjustments work? What types of forces
or frequencies during an adjustment result in the most efficient spinal motion
or the most effective neurophysiological responses? What types of force-time
profiles during chiropractic adjustment are best for which patients? Can we use
such biomechanical or neurophysiological responses as objective outcome measures
for patients? Often as occurs in research, we are left with more questions than
answers.
We have been fortunate to collaborate with
other research groups from around the world to study these important questions.
Our work in human subjects measuring bone movement and neurophysiological
responses during chiropractic adjustments9,11,12 with Robert Gunzburg, M.D.,
Ph.D., an orthopedic surgeon from Antwerp, Belgium has given rise to further
work investigating the effects of different force-time profiles (different kinds
of adjustments) on these variables. We’ve also now progressed to use a
previously developed animal model17 in Sweden to perform more invasive
experiments to quantify the effects of chiropractic adjustments on motor unit
action potentiation (MUAP) (Figure 1).
In other words, with this work, we hope to
determine the effect of chiropractic adjustments on changes in the paraspinal
muscles. The objective of this series of investigations is to quantify the
biomechanical and neurophysiological responses of mechanical stimulation via
spinal manipulation in an animal model. Indeed, should the mechanical
stimulation as delivered via chiropractic adjustment be found to decrease MUAP,
it will help to explain the observed beneficial effects that we see in our
patients every day in clinical practice; improvements in ranges of motion,
functional activities, improved postures, decreased spasm and pain.
In related work, in April, 2004 we traveled down under to collaborate with
award-winning Australian researchers using their animal model to investigate the
effects of varying force-time profiles on bone movement, nerve root, and
neuromuscular responses (Figure 2).
This work is a continuation of the research
that we began with Dr. Gunzburg in human subjects.9-12 Due to the limitations
inherent in human subject research, applied forces delivered to the spine during
SMTs were limited and validation of the research protocol could not be performed
due to its invasiveness. Thus, an animal model is necessary to improve the study
design to allow for examination of the effects of varying force-time and
force-frequency profiles on both biomechanical and neurophysiological responses
prompting the current study design (Figure 3).
We have completed phase 1 of the Australia project and will be returning to
Adelaide to repeat our protocol in animals with induced disc degeneration to
investigate differences between the groups. We are currently analyzing data from
these many projects and you can look forward to hearing more about this research
as we present and publish our results.Only through funding from the generous
support of Dr. William Harris’ Foundation for the Advancement of Chiropractic
Education and Chiropractic Biophysics® Non-profit, Inc., has this research been
made possible.
References
1. Keller TS, Colloca CJ, Fuhr AW. Validation
of the force and frequency characteristics of the activator adjusting
instrument: effectiveness as a mechanical impedance measurement tool. J
Manipulative Physiol Ther 1999;22:75-86.
2. Colloca CJ, Keller TS. Stiffness and
neuromuscular reflex response of the human spine to posteroanterior manipulative
thrusts in patients with low back pain. J Manipulative Physiol Ther
2001;24:489-500.
3. Colloca CJ, Keller TS, Peterson TK, Seltzer
DE. Comparison of dynamic posteroanterior spinal stiffness to plain film
radiographic images of lumbar disk height. J Manipulative Physiol Ther
2003;26:233-41.
4. Keller TS, Colloca CJ, Fuhr AW. In vivo
transient vibration assessment of the normal human thoracolumbar spine. J
Manipulative Physiol Ther 2000;23:521-30.
5. Colloca CJ, Keller TS. Active trunk extensor
contributions to dynamic posteroanterior lumbar spinal stiffness. J Manipulative
Physiol Ther 2004;27:229-37.
6. Nathan M, Keller TS. Measurement and
analysis of the in vivo posteroanterior impulse response of the human
thoracolumbar spine: a feasibility study. J Manipulative Physiol Ther
1994;17:431-41.
7. Keller TS, Colloca CJ, Beliveau JG.
Force-deformation response of the lumbar spine: a sagittal plane model of
posteroanterior manipulation and mobilization. Clin Biomech 2002;17:185-96.
8. Keller TS, Colloca CJ. A rigid body model of
the dynamic posteroanterior motion response of the human lumbar spine. J
Manipulative Physiol Ther 2002;25:485-96.
9. Keller TS, Colloca CJ, Gunzburg R.
Neuromechanical characterization of in vivo lumbar spinal manipulation. Part I.
Vertebral motion. J Manipulative Physiol Ther 2003;26:567-78.
10. Colloca CJ, Keller TS, Gunzburg R.
Biomechanical and neurophysiological responses to spinal manipulation in
patients with lumbar radiculopathy. J Manipulative Physiol Ther 2004;27:1-15.
11. Colloca CJ, Keller TS, Gunzburg R,
Vandeputte K, Fuhr AW. Neurophysiologic response to intraoperative lumbosacral
spinal manipulation. J Manipulative Physiol Ther 2000;23:447-57.
12. Colloca CJ, Keller TS, Gunzburg R.
Neuromechanical characterization of in vivo lumbar spinal manipulation. Part II.
Neurophysiological response. J Manipulative Physiol Ther 2003;26:579-91.
13. Colloca CJ, Keller TS. Electromyographic
reflex response to mechanical force, manually-assisted spinal manipulative
therapy. Spine 2001;26:1117-24.
14. Keller TS, Colloca CJ. Mechanical force
spinal manipulation increases trunk muscle strength assessed by
electromyography: A comparative clinical trial. J Manipulative Physiol Ther
2000;23:585-95.
15. Keller TS, Harrison DE, Colloca CJ,
Harrison DD, Janik TJ. Prediction of osteoporotic spinal deformity. Spine
2003;28:455-62.
16. Harrison DE, Colloca CJ, Harrison DD, Janik
TJ, Haas JW, Keller TS. Anterior thoracic posture increases thoracolumbar disc
loading. Eur Spine J 2004.
17. Indahl A, Kaigle AM, Reikeras O, Holm SH.
Interaction between the porcine lumbar intervertebral disc, zygapophysial
joints, and paraspinal muscles. Spine 1997;22:2834-40.
|
Sponsored By:
|
