Healing Diversity and Other Challenges to Chiropractic Integration
Carl D. Nelson, DC, Daniel Redwood, DC,
David L. McMillin, MA, Douglas G. Richards, PhD, Eric A. Mein, MD
Virginia Beach, VA 23454
[NOTE: This article was published in The Journal of Manipulative
and Physiological Therapeutics, March/April, 2000, Vol. 23,
Submit reprint requests to: Carl D. Nelson, DC, Meridian Institute,
1849 Old Donation Parkway, Suite 1, Virginia Beach, VA 23454, (757) 496-6009.
Chiropractic has made significant strides in establishing
itself as a leading contender for integration in the emerging health care
system. However, recent articles in prominent medical journals illustrate
key issues that must be resolved for chiropractic to fully establish itself
within the new health care model. Manual therapy diversity and the
corollary question of whether chiropractic care should be defined solely
in terms of the high velocity-low amplitude (HVLA) adjustment, are issues
in need of urgent attention and analysis. Other problematic areas affecting
chiropractic's integration into the health care mainstream include research
methodology issues, treatment of visceral disorders, and professional relationships.
Chiropractic has met many challenges in its development
as a healing art. Throughout most of its existence, the chiropractic
profession has battled opposition from organized medicine, suffered financially
as a result of exclusion from health insurance reimbursement, and been
widely regarded as a marginal profession (1). Despite these obstacles,
chiropractic has flourished, becoming the third largest of the learned
health care professions (2). Although the quality and quantity of
chiropractic research during the early years of the profession left much
to be desired (3), modern research has contributed significantly to the
success and acceptance of chiropractic.
With the rapidly changing political and economic
aspects of health care delivery, chiropractic is well situated to make
important contributions to the emerging health care paradigm. However,
to fully participate in this revolution, key issues must be addressed with
regard to manual therapy diversity, research methodology, the treatment
of systemic dysfunction, and professional relations.
MANUAL THERAPY DIVERSITY
Chiropractic is one of the main branches of manual
therapy. Historically, one of the major challenges of chiropractic has
been to define and maintain its unique identity among the various manual
therapy professions. This has often resulted in a competitive stance toward
other forms of manual therapy. Notably, the rift between chiropractic
and osteopathy goes back to the founders of the professions, who openly
debated the conceptual and clinical differences of their respective approaches
(4). Osteopathy has integrated a wide variety of modalities, most
notably the practice of medicine, while chiropractic has remained primarily
focused in the application of manual therapy. While the role of manual
therapy in osteopathy (osteopathic manipulative treatment or OMT) has decreased,
the diversity of techniques practiced by osteopaths has increased. The
minority of osteopaths who practice OMT utilize a broad spectrum of techniques
including inhibitive pressure, soft tissue manipulation, and cranial/sacral
In chiropractic as well, the short lever high velocity/low
amplitude (HVLA) thrust adjustment (typically associated with an audible
cavitation or "cracking" sound) has been supplemented by a wide range of
non-cavitating methods including flexion-distraction, sacro-occipital,
Thompson, Activator, Applied Kinesiology, directional non-force, and dozens
of others. Defining chiropractic strictly in terms of the HVLA adjustment
fails to accurately describe the practice of contemporary chiropractic.
Historically, chiropractic has struggled with the
dilemma of therapeutic diversity in a number of ways. To some extent,
the battle between "purists" and "mixers" continues to this day (5).
Some chiropractors offer a blend of diverse manual therapy techniques in
addition to complementary and alternative medicine (CAM) options including
nutrition, herbal medicine, energy medicine, and physiotherapy. These
DCs view themselves as chiropractic physicians qualified to address a broad
range of disorders, including systemic dysfunction and visceral disease.
Many of these clinicians use methods from the full spectrum of manual therapy,
including soft tissue manipulation. Other chiropractors limit their therapeutic
methods to the hands-on adjustment but apply this method to both somatic
and visceral complaints. Still others feel strongly that the role of chiropractic
should be limited to treating somatic dysfunction, primarily back and neck
Manual therapy diversity is more than an historical
or academic issue. Structuring research to reflect this diversity
poses a significant methodological problem and, if recent, well-publicized
studies are a harbinger of things to come, represents a potential major
stumbling block to chiropractic's full integration into the mainstream
of health care.
ISSUES IN RESEARCH METHODOLOGY
Two studies reported in leading medical journals
illustrate the potential methodological problems confronting chiropractic
researchers. In the New England Journal of Medicine, Balon
et al. (6) compared "active" and "simulated" chiropractic manipulation
as adjunctive treatment for childhood asthma.
The active treatment consisted of "manual contact
with spinal or pelvic joints followed by low-amplitude, high velocity directional
push often associated with joint opening, creating a cavitation, or 'pop'."
This treatment is a standard direct technique used by a wide variety of
manual therapy practitioners, primarily chiropractors and osteopaths.
The simulated treatment involved:
* "soft-tissue massage and gentle palpation" to the spine, paraspinal
muscles, and shoulders
* "turning the subject's head from one side to the other"
* "a nondirectional push, or impulse" to the gluteal area with the
subject lying on one side and then the other
* with the subject in the prone position, "a similar impulse was applied
bilaterally to the scapulae"
* the subject in a supine position "with the head rotated slightly
to each side, and an impulse applied to the external occipital protuberance"
* "low-amplitude, low-velocity impulses were applied in all these nontherapeutic
contacts, with adequate joint slack so that no joint opening or cavitation
Jongeward (7) questioned the appropriateness of the
simulated treatment, noting that that standard chiropractic practice commonly
includes soft tissue work. Furthermore, the sham treatment in the Balon
et al. study bears a marked similarity to a traditional general osteopathic
treatment (8-10). The Early American Manual Therapy website
provides easy access to several such examples from the traditional manual
therapy literature (11).
The authors of the Balon et al. study summarized
the simulated treatment by stating, "Hence, the comparison of treatments
was between active spinal manipulation as routinely performed by chiropractors
and hands-on procedures without adjustments or manipulation." Apparently,
these investigators were unaware of the early osteopathic works addressing
asthma (8-10) and more recent literature on OMT for respiratory problems
in general, particularly as cited in Osteopathic Considerations in Systemic
Dysfunction (12). The methodological limitations of the Balon et al. study
with regard to manual therapy were noted by Richards et al. (13). Balon
et al. (14) responded that they were unconvinced by the evidence supporting
the efficacy of the simulated treatment.
The results as reported by the researchers were,
"Symptoms of asthma and use of ß-agonists decreased and the quality
of life increased in both groups, with no significant differences between
the groups." Based on this equality of improvement, the authors concluded,
"the addition of chiropractic spinal manipulation to usual medical care
provided no benefit," (6). In our view, this is unfortunate, because the
data clearly indicate that the subjects in both groups improved after being
treated by diverse forms of manual therapy.
Another article, reported in the Journal of the
American Medical Association, also fails to accurately portray and
interpret manual therapy diversity. In certain respects, "Spinal
Manipulation in the Treatment of Episodic Tension-Type Headache" (15) duplicates
the questionable methodological choices in the Balon et al. study.
The researchers compared two forms of manual therapy for the treatment
of tension headache. The experimental treatment consisted of HVLA
chiropractic adjustments and deep friction massage plus trigger point therapy
(if indicated). The subjects receiving this intervention were designated
as the "manipulation" group. The "active control" group received
deep friction massage plus low-power laser light (considered not to be
efficacious for tension headache). Thus, as in the asthma study,
one form of manual intervention was compared to another.
The researchers observed that "by week 7, each group experienced significant
reductions in mean daily headache hours" and mean number of analgesics
per day." But because both groups benefited equally from the diverse forms
of manual therapy, the authors concluded that, "as an isolated intervention,
spinal manipulation does not seem to have a positive effect on episodic
tension-type headaches." (15, p. 1576). Unlike the Balon study, this carefully
worded conclusion is technically correct, though it would also have been
technically correct to conclude that both massage and manipulation plus
massage resulted in measurable improvements for tension headache sufferers.
Both the headache and the asthma studies were widely
reported in the mass media as demonstrating that chiropractic fails to
help patients with childhood asthma and tension headache. In our view,
a more informative conclusion is that diverse forms of manual therapy appear
to be at least mildly helpful for these conditions. Although the favorable
outcomes could have resulted from chance or placebo effects, a reasonable
person might also justifiably conclude that various forms of manual medicine
can be helpful for these conditions. The diversity and potential validity
of the full spectrum of manual therapy applications significantly confounds
Although less publicized, Nilsson (16) used the same
methodology in an earlier study on cervicogenic headache (n=39). Standard
chiropractic (HVLA spinal manipulation) was compared to deep massage, trigger
point therapy and light therapy (control treatment). The subjects
in both the experimental and control groups showed notable improvement.
There was no statistical difference in the outcomes between the two groups.
Ironically and disconcertingly, Nilsson specifically noted in this earlier
article that, "the control group in the present study (massage/trigger
points) is normally assumed to have some effect on this group of headaches."
He further noted the inherent methodological shortcomings of using such
a group as a control: "Future studies need necessarily include higher numbers
of experimental subjects, but should take care to use an absolutely inert
control treatment (for example, low-level laser only)." (16, p. 440)
One can only wonder why Nilsson elected not to follow his own clearly stated
recommendation, and instead used the same admittedly questionable methodology
in the later tension-headache study.
Future research must seriously consider the full
spectrum of diverse manual therapy options rather than assuming that some
forms are ineffective and can therefore be used as sham treatments. Legitimate
alternative methodologies exist, particularly direct comparisons of chiropractic
procedures (allowing the full range of methods typically used by chiropractors
in real-world practice settings) versus standard medical care. Some comparative
studies (17-21) have shown chiropractic equal or superior to conventional
medical procedures, with fewer side effects. If fairly constructed, future
studies of this type will yield data that allow health practitioners and
the general public to place manual therapy procedures in proper context.
Comparing manual therapy to highly questionable placebos confuses the issue,
and delays the advent of a level playing field (22).
MANUAL THERAPY AND SYSTEMIC DYSFUNCTION
Apart from the diversity issue, the other fundamental
question raised by these studies is the possible influence of chiropractic
(and by inference other primary forms of manual therapy) in the treatment
of systemic dysfunction. Is manual therapy only helpful for somatic
dysfunction (i.e., back and neck pain), or can systemic dysfunction (including
visceral disease) also be effectively treated by chiropractors and other
manual therapy practitioners?
Interestingly, the origins of both chiropractic and
osteopathy can be traced to positive outcomes in the treatment of systemic
dysfunction. D. D. Palmer's treatment of a patient with hearing impairment
marks the beginning of chiropractic (23). A. T. Still used an inhibitive
technique (lying with his head in a sling) to relieve his own headaches.
This, in addition to his grief over the death of three of his children
from meningitis despite the best available medical treatment, drove Still
to create a system for healing systemic dysfunction (24).
In recent years, the treatment of systemic dysfunction
by chiropractors has declined (25), although reports of effective treatment
for nonmusculoskeletal problems continue to be published (26-29). Although
osteopathy has seen a general decrease in the use of manual therapy, interest
still exists with regard to the treatment of systemic dysfunction
To clarify the role of manual therapy in the treatment
of systemic dysfunction, Sawyer et al., (1) recommended clinical research
aimed at investigating outcomes and effectiveness of chiropractic care
on somatovisceral disorders. The priority list of disorders included
dysmenorrhea, asthma, otitis media, essential hypertension, irritable bowel
syndrome, and peptic disorders. This research has begun, but is still in
a preliminary phase.
This is a controversial topic with profound ramifications
for the future role of chiropractic in the overall health care system.
With recent changes in the health care system toward incorporation of CAM
approaches, chiropractic has emerged as a leading candidate for integration
in the new health care model. Thus far, however, this has been predicated
on an implicit assumption that chiropractic's therapeutic domain is the
treatment of somatic disease. In large measure, chiropractic is perceived,
rightly or wrongly, as a form of specialized physical therapy. If chiropractic
is to be smoothly integrated into the health care mainstream, the path
of least resistance calls for dropping the notion of manual therapy for
systemic dysfunction. To do so, however, would fly in the face of a century
of chiropractic practice.
Manual therapy for systemic dysfunction is controversial
from a scientific perspective. Nansel and Szlazak provide a comprehensive
and insightful review of the conceptual and biological problems associated
with the systemic dysfunction issue (30). Basically, these authors
reframe the apparent influence of manual therapy on systemic dysfunction
as an etiological misunderstanding, the result of misdiagnosis. According
to Nansel and Szlazak, the visceral symptoms in question are actually "somatic
mimicry syndromes" produced by somatic nerve reflexes which simulate (rather
than cause) internal organ disease. Thus, chiropractic treatment
in such cases merely removes the "somato-somatic reflex." The abundance
of citations provided by the authors strongly supports their position of
the improbability of manipulation's effects on true somato-visceral disease.
However, a more recent article by Sato presents strong biological evidence
of somato-visceral reflexes in animals, where cutaneous stimulation of
somatic afferents evokes reflex sympathetic efferent activity. Sato's
basic scientific work appears to strongly support the concept of somato-visceral
disease. Sato's conclusion is that "a great deal of work remains
to be done." (31, p. 601). It is noteworthy that Sato's studies have
been presented in osteopathic and chiropractic publications (32), and have
appeared in a variety of neurophysiology journals as well (33-36).
Sato's nonpolitical, interdisciplinary approach is exemplary of the cooperative
attitude needed in this type of research.
What role will chiropractic play in the emerging
health care system? As Lamm et al. (37) have asked, "Are chiropractors
portal-of-entry physicians, primary care givers, first contact physicians,
generalists, specialists, or a hybrid of these?" In order to establish
and maintain constructive relationships with other health care providers,
chiropractors must come to terms with who they are and what they do. The
process of integration into the evolving health care system may involve
an identity crisis for chiropractors.
As a group, chiropractors are highly individualistic
and independent. With changes in the health care system, opportunities
are being created for chiropractors with the ability to adapt and cooperate
to become more fully integrated into mainstream health care. Therefore,
as the health care system is reformed, relationships with other professionals
become a critical issue. The previous discussions of manual therapy
diversity and the treatment of systemic dysfunction are relevant to evolving
patterns of professional interaction.
To take one important example, will interactions
with osteopaths become more collegial rather than perpetuating the historical
division between chiropractic and osteopathy? Will respect for manual
therapy diversity become the new ideal? Cooperation makes sense.
Osteopathic research and clinical experience can contribute to chiropractic
efficacy and vice versa. Perhaps some chiropractors worry that too
close a relationship with osteopaths may be contagious - that whatever
prompted most osteopaths to largely abandon manual therapy will somehow
While this fear is based on a kernel of truth, the
future of chiropractic need not mirror the past and present of osteopathy.
One crucial difference is that, unlike the osteopathic profession, chiropractic's
political and academic leadership, and the vast majority of today's practitioners,
are united in support of maintaining the profession's central emphasis
on the core concepts of chiropractic - the link between structure and function,
the critical mediating role of the nervous system, and the primacy of the
adjustment in chiropractic practice. This is strongly supported by both
ACA and ICA, and was unanimously endorsed by all North American chiropractic
college presidents at the historic 1996 meeting of the Association of Chiropractic
Colleges. (38). Most significantly, no broad-based chiropractic political
organization or educational institution has ever endorsed giving up manual
therapy or limiting its application to strictly musculoskeletal conditions.
While working at building relationships with practitioners
of other health professions, chiropractic must also attend to splits within
its own house. Traditional conflicts between "straights" and "mixers" are
well-known and continue to be a source of contention. A modern counterpart
of this division is the primary care physician/manual therapy specialist
distinction. Some chiropractors endorse an exclusively somatic dysfunction
model. At the same time, other DCs are carving out a niche as primary care
physicians by treating somatic and systemic dysfunction with a broad range
of therapeutic modalities. Others, perhaps the majority of the profession,
find themselves in the middle ground between these two poles. While
basic research and outcomes studies may help to eventually resolve this
split, such resolution is unlikely to occur soon.
The interdisciplinary team model is a plausible vehicle
for passage to a more diverse and integrated health care system.
Lawrence (39) suggests that the rural setting is an ideal environment for
interdisciplinary teams with chiropractic members, but also recognizes
the inherent challenges of such cooperation:
"The involvement of chiropractors as members of interdisciplinary
teams will no doubt suffer from initial problems, such as lack of professional
acceptance by medical physicians and nurses, ill-defined roles for chiropractors,
intraprofessional conceptual challenges (for example, will we be autonomous
in decision making on a par with other professionals?), etc." (39, p. 78)
The increasing interest in CAM therapies is an especially
promising track for improved professional relations. Interdisciplinary
teams which include CAM practitioners are increasing, especially on the
West Coast and in large urban areas in other parts of the country (40).
If chiropractors are unable or unwilling to create a niche in such groups,
other manual therapy practitioners (ranging from massage therapy to reflexology
to therapeutic touch) may fill the void.
Emphasis on research is helpful in these settings.
Honest research acknowledges an openness and desire to learn. These
are essential qualities for members of an interdisciplinary research team.
Research also provides an umbrella for mainstream practitioners to safely
The authors of this article are members of an interdisciplinary
team with diverse backgrounds in chiropractic, medicine, osteopathy, biology,
and psychology. The rich diversity of the group enhances the research
process. Manual therapy diversity is not a problem, but an opportunity
to explore the efficacy of a variety of techniques. Likewise, the
use of manual therapy for systemic dysfunction is an enticing hypothesis
that will require much time and effort to test. Commitment to an
ideal higher than the advancement of a particular profession is necessary
for such teams to work closely together over time. Such an ideal
may be as simple and direct as improving the quality of patient care via
whatever means available.
Health care is in a time of great change. Chiropractic
has much to offer the new health care system. With its rich heritage of
therapeutic pragmatism, its growing body of research, and its well-developed
professional infrastructure (41), the profession is well positioned to
influence the future direction of health care. However, to fully
participate in this transition, several key questions must be addressed.
* Will chiropractic be defined solely in terms of the high velocity/low
amplitude thrust adjustment or in terms of the full spectrum of manual
* Can chiropractic provide efficacious treatment of systemic dysfunction
or will it be limited to the treatment of musculoskeletal ailments?
* Will chiropractic research address the methodological pitfalls which
result from a failure to recognize the diversity of manual therapy approaches?
* Will further basic research into the biological mechanisms of somato-viseral
disease be pursued?
* Will the common ground between chiropractic and other forms of manual
therapy (particularly osteopathy) be recognized and utilized?
* Will the economic and political pressures to integrate into the mainstream
diminish the unique contributions of chiropractic?
* Will chiropractors be viewed as doctors equipped to address a wide
range of human ills or as specialists in advanced musculoskeletal physical
These are controversial questions worthy of discussion
and debate. Chiropractic is at a crossroads. The direction
taken by today's chiropractors may well influence the role of manual therapy
for years to come.
Historically, chiropractic has maintained itself
as a relatively independent entity. Initially, chiropractic education,
research, and clinical practice were isolated from the mainstream due to
a variety of factors (1). Despite undeniable progress, for the most
part chiropractors are still outsiders looking in. Now that the door
has begun to swing open, will chiropractic come into the mainstream?
In the past, chiropractic had to distinguish itself
to survive. Emphasizing differences between itself and other similar professions
(especially osteopathy) was helpful in creating a unique identity. While
maintaining identity is still important, chiropractic has matured to the
point where it can benefit from mutually beneficial professional
relationships. As health care reforms continue, it will be helpful
to emphasize common ground rather than exaggerating differences.
Where differences exist, acknowledging diversity without attacking will
increase the chances of building positive professional relationships.
As long as chiropractic provides cost-effective,
efficacious service, its future is bright. A strong commitment to
research (both basic and clinical) is needed to document the efficacy of
chiropractic treatment, while defining its limitations. Chiropractors
must come to terms with manual therapy diversity. The treatment of
systemic dysfunction via manual therapy will continue to be a controversial
topic. Improved research design is essential, especially to avoid
disregarding positive outcomes when manual therapy is used for systemic
dysfunction. Interdisciplinary research teams offer a promising means
of integration of chiropractic with other treatment modalities and improved
1. Sawyer C, Haas M, Nelson C, Elkington W. Clinical research
with the chiropractic profession: status, needs and recommendations. J
Manipulative Physiol Ther 1997; 20:169-78.
2. Mootz RD, Coulter ID, Hansen DT. Health services research related
to chiropractic: review and recommendations for research prioritization
by the chiropractic profession. J Manipulative Physiol Ther 1997; 201-17.
3. Keating JC Jr., Green, BN, Johnson, CD. "Research" and "science"
in the first half of the chiropractic century. J Manipulative Physiol
Ther 1995; 18:357-78.
4. Brantingham JW. Still and Palmer: the impact of the first osteopath
and the first chiropractor. Chiropractic History 1986; 6: 19-22.
5. Keating JC. Purpose-straight chiropractic: not science, not
health care. J Manipulative Physiol Ther 1995; 18:416-18.
6. Balon J, Aker PD, Crowther ER, Danielson C, Cox PG, O'Shaughnessy
D, Walker C, et al. A comparison of active and simulated chiropractic
manipulation as adjunctive treatment for childhood asthma. N Engl
J Med 1998; 339:1013-20.
7. Jongeward BV. Chiropractic manipulation for childhood asthma.
N Engl J Med 1999; 340:391-2.
8. Hazzard C. The practice and applied therapeutics of osteopathy.
3rd ed. Kirksville, MO: Journal Printing Company; 1905. p. 75-80.
9. Barber ED. Osteopathy complete. 4th Ed. Kansas City, MO: Hudson-Kimberly
Publishing Company; 1898. p. 60-8.
10. Goetz, EW. A manual of osteopathy. 2nd ed. Cincinnati, OH: Nature's
Cure Co.; 1909. p. 85-6.
11. McMillin D. The Early American Manual Therapy website is
located at: http://members.visi.net/~mcmillin/; 1998.
12. Kuchera M, Kuchera WA. Osteopathic considerations in systemic
dysfunction. Kirksville, MO: KCOM Press; 1991.
13. Richards DG, Mein EA, Nelson CD. Chiropractic manipulation
for childhood asthma. N Engl J Med 1999; 340:391-2.
14. Balon J, Crowther ER, Sears MR. Chiropractic manipulation
for childhood asthma. N Engl J Med 1999; 340:392.
15. Bove G, Nilsson N. Spinal manipulation in the treatment of episodic
tension-type headache. JAMA 1998; 280:1576-9.
16. Nilsson N. A randomized controlled trial of the effect of spinal
manipulation in the treatment of cervicogenic headache. J Manipulative
Physiol Ther 1995; 18:435-40.
17. Meade TW, Dyer S, Browne W et al: Low back pain of mechanical origin:
randomized comparison of chiropractic and hospital outpatient treatment.
Br Med J 1990; 300:1431-7
18. Meade TW, Dyer S, Browne W et al: Randomised comparison of chiropractic
and hospital outpatient management for low back pain: results from extended
follow-up. Br Med J 1995; 311:349-50.
19. Boline PD, Kassem K, Bronfort G, Nelson C, Anderson AV. Spinal
manipulation vs. amitriptyline for the treatment of chronic tension-type
headache: a randomized clinical trial. J Manipulative Physiol Ther 1995;
20. Winters JC, Sobel JS, Groenier KH et al: Comparison of physiotherapy,
manipulation, and corticosteroid injection for treating shoulder complaints
in general practice: randomised, single blind study. Br Med J 1997; 314:1320-5.
21. Nelson CF, Bronfort G, Evans R et al. The efficacy of spinal manipulation,
amitriptyline and the combination of both therapies for the prophylaxis
of migraine headache. J Manipulative Physiol Ther 1998; 21:511-9
22. Redwood D. Same data, different interpretation. J Altern Complement
Med 1999; 5:89-91.
23. Palmer DD. The science, art and philosophy of chiropractic.
Portland (OR): Portland Publishing House; 1910.
24. Still AT. Autobiography of Andrew Taylor Still. Kirksville, MO:
Published by the author; 1897.
25. ACA Department of Statistics completes 1989 Survey. J Manipulative
Physiol Ther 1990; 27:80.
26. Gorman RF. The treatment of presumptive optic nerve ischemia
by spinal manipulation. J Manipulative Physiol Ther 1995; 18:172-7.
27. Froehle RM. Ear infection: a retrospective study examining
improvement from chirpractic care and analyzing for influencing factors.
J Manipulative Physiol Ther 1996; 19:169-77.
28. Stude DE, Bergmann TF, Finer BA. A conservative approach
for a patient with traumatically induced urinary incontinence. J
Manipulative Physiol Ther 1998; 21:363-7.
29. Haas, M. Chiropractic management of primary nocturnal enuresis.
J Manipulative Physiol Ther 1995; 18:638-41.
30. Nansel D, Szlazak M. Somatic dysfunction and the phenomenon
of visceral disease simulation: a probable explanation for the apparent
effectiveness of somatic therapy in patients persumed to be suffering from
true visceral disease. J Manipulative Physiol Ther 1995; 18:379-97.
31. Sato A. Somatovisceral reflexes. J Manipulative Physiol
Ther 1995; 18:597-602.
32. Sato A. Reflex modulation of visceral functions by somatic
afferent activity. In: Patterson, MM, Howell, JN, editors. The central
connection: Somatovisceral/Viscerosomatic interaction. 1989 International
Symposium. Athens, Ohio: American Academy of Osteopathy; 1992. p.
33. Sato A, Schmidt RF. Muscle and cutaneous afferents evoking
sympathetic reflexes. Brain Res 1966; 2:399-401.
34. Sato A, Sato Y, Suzuki A, Uchida S. Neural mechanisms of
the reflex inhibition and excitation of gastric motility elicited by acupuncture-like
stimulation in anesthetized rats. Neurosci Res 1993; 18:53-62.
35. Sato A, Sato Y, Sugimoto H, Terui N. Reflex changes in the
urinary bladder after mechanical and thermal stimulation of the skin at
various segmental levels in cats. Neuroscience 1977; 2:111-7.
36. Araki T, Ito K, Kurosawa M, Sato A. Responses of adrenal sympathetic
nerve activity and catecholamine secretion to cutaneous stimulation in
anesthetized rats. Neuroscience 1984; 12:289-99.
37. Lamm LC, Wedner E, Collord D. Chiropractic scope of practice:
what the law allows - update 1993. J Manipulative Physiol Ther 1995;
38. Cleveland CS III. Vertebral subluxation. In Redwood D, editor.
Contemporary chiropractic. New York: Churchill Livingstone; 1997. p. 29-44.
39. Lawrence DJ. Chiropractic and rural health. J Manipulative
Physiol Ther 1996; 19:75-81.
40. Hawk C, Nyiendo J, Lawrence D, Killinger L. The role of chiropractors
in the delivery of interdisciplinary health care in rural areas.
J Manipulative Physiol Ther 1996; 19:82-91.
41. McAndrews JF. Appropriate Care, Ethics and Practice Guidelines.
In Redwood D, editor. Contemporary chiropractic. New York: Churchill Livingstone;
1997. p. 219-227.