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'''Vertebral subluxation''' is a ] term that is used to describe a myriad of signs and symptoms (]) thought to occur as a result of a misaligned or dysfunctional ] ]. The chiropractic subluxation complex is a ] biomechanical spinal lesion with purported altered neurological function that can result in neuromusculoskeletal and ] disorders. Officially, the ] definition of the chiropractic vertebral subluxation is: ''"A lesion or dysfunction in a joint or motion segment in which alignment, movement integrity and/or physiological function are altered, although contact between joint surfaces remains intact. It is essentially a functional entity, which may influence biomechanical and neural integrity."'' The degree of structural displacement is not necessarily ''"visible on ]."''<ref name="WHO_guidelines">, p. 4, including footnote</ref> This is in contrast to the medical definition of spinal ] which, according to the WHO, is a ''"significant structural displacement, and therefore visible on ]."''<ref name="WHO_guidelines"/> '''Vertebral subluxation''' is a ] term that is used to describe a myriad of signs and symptoms (]) thought to occur as a result of a misaligned or dysfunctional ] ]. The chiropractic subluxation complex is a ] biomechanical spinal lesion with purported altered neurological function that can result in neuromusculoskeletal and ] disorders. Officially, the ] definition of the chiropractic vertebral subluxation is: ''"A lesion or dysfunction in a joint or motion segment in which alignment, movement integrity and/or physiological function are altered, although contact between joint surfaces remains intact. It is essentially a functional entity, which may influence biomechanical and neural integrity."'' The degree of structural displacement is not necessarily ''"visible on ]."''<ref name="WHO_guidelines">, p. 4, including footnote</ref> This is in contrast to the medical definition of spinal ] which, according to the WHO, is a ''"significant structural displacement, and therefore visible on ]."''<ref name="WHO_guidelines"/>
The chiropractic vertebral subluxation complex has been a source of controversy and confusion since its inception in 1895 - with critics both inside and outside the profession - due to its ] origins and claims of far reaching effects. Although research into the significance of the chiropractic vertebral subluxation is ongoing, it generally does not have the support of mainstream medicine<ref name=Campbell>{{cite journal |journal=Pediatrics |year=2000 |volume=105 |issue=4 |pages=e43 |title= Chiropractors and vaccination: a historical perspective |author= Campbell JB, Busse JW, Injeyan HS |quote=... considered disease the result of spinal nerve dysfunction caused by misplaced (subluxated) vertebrae. Although rejected by medical science, this concept is still accepted by a minority of chiropractors. |pmid=10742364 |url=http://pediatrics.aappublications.org/cgi/content/full/105/4/e43 |doi= 10.1542/peds.105.4.e43}}</ref> and is not based on solid science.<ref name=Ernst-eval>{{cite journal |journal= ] |date=2008 |volume=35 |issue=5 |pages=544–62 |title= Chiropractic: a critical evaluation |author= Ernst E |doi=10.1016/j.jpainsymman.2007.07.004 |pmid=18280103}}</ref> The chiropractic vertebral subluxation complex has been a source of controversy and confusion since its inception in 1895 - with critics both inside and outside the profession - due to its ] origins and claims of far reaching effects. Although research into the significance of the chiropractic vertebral subluxation is ongoing, it generally does not have the support of mainstream medicine.<ref name=Campbell>{{cite journal |journal=Pediatrics |year=2000 |volume=105 |issue=4 |pages=e43 |title= Chiropractors and vaccination: a historical perspective |author= Campbell JB, Busse JW, Injeyan HS |quote=... considered disease the result of spinal nerve dysfunction caused by misplaced (subluxated) vertebrae. Although rejected by medical science, this concept is still accepted by a minority of chiropractors. |pmid=10742364 |url=http://pediatrics.aappublications.org/cgi/content/full/105/4/e43 |doi= 10.1542/peds.105.4.e43}}</ref>


== History == == History ==

Revision as of 12:19, 26 May 2009

Vertebral subluxation is a chiropractic term that is used to describe a myriad of signs and symptoms (syndrome) thought to occur as a result of a misaligned or dysfunctional spinal segment. The chiropractic subluxation complex is a functional biomechanical spinal lesion with purported altered neurological function that can result in neuromusculoskeletal and visceral disorders. Officially, the WHO definition of the chiropractic vertebral subluxation is: "A lesion or dysfunction in a joint or motion segment in which alignment, movement integrity and/or physiological function are altered, although contact between joint surfaces remains intact. It is essentially a functional entity, which may influence biomechanical and neural integrity." The degree of structural displacement is not necessarily "visible on static imaging studies." This is in contrast to the medical definition of spinal subluxation which, according to the WHO, is a "significant structural displacement, and therefore visible on static imaging studies."

The chiropractic vertebral subluxation complex has been a source of controversy and confusion since its inception in 1895 - with critics both inside and outside the profession - due to its metaphysical origins and claims of far reaching effects. Although research into the significance of the chiropractic vertebral subluxation is ongoing, it generally does not have the support of mainstream medicine.

History

B. J. Palmer stated that:

"Chiropractors have found in every disease that is supposed to be contagious, a cause in the spine. In the spinal column we will find a subluxation that corresponds to every type of disease. If we had one hundred cases of small-pox, I can prove to you where, in one, you will find a subluxation and you will find the same conditions in the other ninety-nine. I adjust one and return his functions to normal... . There is no contagious disease... . There is no infection... . There is a cause internal to man that makes of his body in a certain spot, more or less a breeding ground . It is a place where they can multiply, propagate, and then because they become so many they are classed as a cause."

Components

Traditionally there have been 5 components that form the chiropractic subluxation. The vertebral subluxation complex is differentiated by the fifth component, general systemic disturbances secondary to the spinal misalignment (vertebral subluxation).

  1. Spinal Kinesiopathology
  2. Neuropathophysiology/Neuropathology
  3. Myopathology
  4. Histopathology
  5. Pathophysiology/Pathology

Examination

Historically, the detection of spinal misalignments (subluxations) by the chiropractic profession has relied on X-ray findings and physical examination. At least 2 of the following 4 physical signs and/or symptoms must be documented to qualify for reimbursement:

  • Pain and tenderness
  • Asymmetry/misalignment
  • Range of motion abnormality
  • Tissue/tone changes

Background

It has been proposed that a vertebral subluxation can negatively affect general health by altering the neurological communication between the brain, spinal cord and peripheral nervous system. Although individuals may not always be symptomatic, straight chiropractors believe that the presence of vertebral subluxation is in itself justification for correction via spinal adjustment.

Chiropractic treatment of vertebral subluxation focuses on delivering a chiropractic adjustment which is a high velocity low amplitude (HVLA) thrust to the dysfunctional spinal segments to help correct the chiropractic subluxation complex. Spinal manipulation is the primary procedure used by chiropractors in the adjustment. Manipulation has been shown to help with low back pain, neck pain and tension type headaches, but further studies are inconclusive on the use of spinal manipulation outside the treatment of neuromusculoskeletal disorders.

Rationale

According to the founder of Chiropractic, D.D. Palmer:

"Physiologists divide nerve-fibers, which form the nerves, into two classes, afferent and efferent. Impressions are made on the peripheral afferent fiber-endings; these create sensations which are transmitted to the center of the nervous system. Efferent nerve-fibers carry impulses out from the center to their endings. Most of these go to muscles and are therefore called motor impulses; some are secretory and enter glands; a portion are inhibitory their function being to restrain secretion. Thus, nerves carry impulses outward and sensations inward. The activity of these nerves, or rather their fibers, may become excited or allayed by impingement, the result being a modification of functionating — too much or not enough action — which is disease."

Chiropractors use and have used various terms to express this concept: subluxation, vertebral subluxation (VS), vertebral subluxation complex (VSC), "killer subluxations," the "silent killer," or a "bone out of place" (BOOP).

Functional theories

Spinal nerve roots
The formation of the spinal nerve from the dorsal and ventral roots
A spinal nerve with its anterior and posterior roots.
Details
Identifiers
Latinradix posterior
Anatomical terminology[edit on Wikidata]

V. Strang, D.C., describes several hypotheses on how a misaligned vertebra may cause interference to the nervous system in his book, Essential Principles of Chiropractic:

  • Nerve compression hypothesis: suggests that when the vertebrae are out of alignment, the nerve roots and/or spinal cord can become pinched or irritated. While the most commonly referenced hypothesis, and easiest for a patient to understand, it may be the least likely to occur.
  • Proprioceptive insult hypothesis: focuses on articular alterations causing hyperactivity of the sensory nerve fibers.
  • Somatosympathetic reflex hypothesis: all the visceral organ functions can be reflexly affected by cutaneous or muscular stimulation.
  • Somatosomatic reflex hypothesis: afferent impulses from one part of the body can result in reflex activity in other parts of the body.
  • Viscerosomatic reflex hypothesis: visceral afferent fibers cause reflex somatic problems.
  • Somatopsychic hypothesis: the effects of a subluxation on the ascending paths of the reticular activating system.
  • Neurodystrophic hypothesis: focuses on lowered tissue resistance that results from abnormal innervation.
  • Dentate ligament-cord distortion hypothesis: upper cervical misalignments can cause the dentate ligaments to put a stress on the spinal cord.
  • Psychogenic hypothesis: emotions, such as stress, causing contraction in skeletal muscles.

The vertebral subluxation has been described as a syndrome with signs and symptoms which include: altered alignment; aberrant motion; palpable soft tissue changes; localized/referred pain; muscle contraction or imbalance; altered physiological function; reversible with adjustment/manipulation; focal tenderness.

Scientific investigation

The investigation of vertebral subluxation has been ongoing since it was first postulated in 1895. The early practitioners used palpation and the anatomy of the nervous system as a guide (meric system). In their efforts to be more specific, they seized the newly discovered X-ray technology and introduced the neurocalometer (a heat sensing device). It was during those early years that the medical establishment first criticized the chiropractic profession, saying that the conditions that those early chiropractors were treating were only psychophysiologic disorders. To prove that chiropractic patients had real conditions, BJ Palmer opened a research clinic as a part of the Palmer College of Chiropractic. When a patient entered the clinic, they were first examined by medical doctors and a diagnosis was formulated. They were then sent to the chiropractic part of the clinic, treated, and sent back to the medical doctors for evaluation. Since then, chiropractors have sought a greater understanding of the mechanisms and effects of the vertebral subluxation. Today we see motion x-rays, surface EMG, and digital thermography though none of these methods have been proven to be reliable or valid in the detection of vertebral subluxations.

As research projects are able to employ new techniques and technologies to evaluate nervous system function and effects, further support for chiropractic principles has surfaced. Chiropractors have long suggested that spinal joint fixation that results from subluxation will result in degenerative effects that compromise the spinal joints. A 2004 research team at the National University of Health Sciences evaluated changes of the lumbar vertebral column following fixation (immobility) by surgically fusing spinal joints in experimental rats. The fixated joints showed significant degeneration compared to the mobile joints, confirming that surgical fixation results in time-dependent degenerative changes of the zygapophysial joints.

Autonomic Nervous System
Blue = parasympathetic
Red = sympathetic

Chiropractic also asserts that spinal health and function are directly related to general health and well-being. Preliminary research concerning the intricate functioning of the nervous system suggests that this speculation may have some support. David Seaman, DC, MS reviewed the work of several researchers concerning autonomic nervous system relationship to the somatic tissues of the spine. He noted that Feinstein et al. were the first to clearly describe some symptoms associated with noxious irritation of spinal tissues. They injected hypertonic saline into interspinous tissues and paraspinal muscles of normal volunteers for the purpose of characterizing local and referred pain patterns that might develop. His observations included:

"The pain elicited from muscles was accompanied by a characteristic group of phenomena which indicated involvement of other than segmental somatic mechanisms. . . . The manifestations were pallor, sweating bradycardia, fall in blood pressure, subjective faintness, and nausea, but vomiting was not observed. Syncope occurred in two early procedures in the series of paravertebral injections and was subsequently avoided by quickly depressing the subject's head or by having him lie down at the first sign of faintness. These features were not proportional to the severity of or to the extent of radiation; on the contrary, they seemed to dominate the experience of subjects who complained of little pain, but who were overwhelmed by this distressing complex of symptoms."

Feinstein referred to these symptoms as autonomic concomitants. It is likely that these autonomic concomitants were caused by nociceptive stimulation of autonomic centers in the brainstem, particularly the medulla. Feinstein indicated that "this is an example of the ability of deep noxious stimulation to activate generalized autonomic responses independently of the relay of pain to conscious levels." In other words, pain may not be the symptomatic outcome of nociceptive stimulation of spinal structures. Such a conclusion has profound implications for the chiropractic profession. Clearly, patients do not need to be in pain to be candidates for spinal adjustments.

The efficacy and validity of spinal manipulation to address visceral disorders systems remains and is a source of controversy within the chiropractic and medical communities. Though research is ongoing on this topic, conclusions that support or refute the usefulness of spinal manipulation on organic disorders remains to be seen. Additionally, to complicate matters, chiropractic professors and researchers, Nansel and Szlazak, found that:

"the proper differential diagnosis of somatic (musculoskeletal) vs. visceral (organ) dysfunction represents a challenge for both the medical and chiropractic physician. The afferent convergence mechanisms, which can create signs and symptoms that are virtually indistinguishable with respect to their somatic vs. visceral etiologies, suggest it is not unreasonable that this somatic visceral-disease mimicry could very well account for the "cures" of presumed organ disease that have been observed over the years in response to various somatic therapies (e.g., spinal manipulation, acupuncture, Rolfing, Qi Gong, etc.) and may represent a common phenomenon that has led to "holistic" health care claims on the part of such clinical disciplines." Considering this phenomenon, Seaman suggests that the chiropractic concept of joint complex (somatic) dysfunction should be incorporated into the differential diagnosis of pain and visceral symptoms because these dysfunctions often generate symptoms similar to those produced by true visceral disease and notes that this mimicry leads to unnecessary surgical procedures and medications.

Other chiropractic researchers have also questioned some of the claimed effects of vertebral subluxation:

"The literature supports the existence of somatovisceral and viscerosomatic reflexes, but there is little or no evidence to support the notion that the spinal derangements (often referred to as subluxations by chiropractors) can cause prolonged aberrant discharge of these reflexes. Equally unsupported in the literature is the notion that the prolonged activation of these reflexes will manifest into pathological state of tissues, and most relevantly, that the application of spinal manipulative therapy can alter the prolonged reflex discharge or be associated with a reversal of the pathological degeneration of the affected reflexes or tissues. The evidence that has been amassed is largely anecdotal or case report based and it has attracted much intra disciplinary debate because of its frequent association with certain approaches to management (largely described as being traditional or "philosophical" in nature)."

Still other chiropractic researchers state quite directly:

"... early chiropractic philosophy ... considered disease the result of spinal nerve dysfunction caused by misplaced (subluxated) vertebrae. Although rejected by medical science, this concept is still accepted by a minority of chiropractors."
"Indeed, many progressive chiropractors have rejected the historical concept of the chiropractic subluxation in favor of ones that more accurately describe the nature of the complex joint disfunctions they treat."

Researchers at the RMIT University-Japan, Tokyo studied reflex effects of vertebral subluxation with regards to the autonomic nervous system. They found that "recent neuroscience research supports a neurophysiologic rationale for the concept that aberrant stimulation of spinal or paraspinal structures may lead to segmentally organized reflex responses of the autonomic nervous system, which in turn may alter visceral function."

Professor Philip S. Bolton of the School of Biomedical Sciences at University of Newcastle, Australia writes in Journal of Manipulative and Physiological Therapeutics, "The traditional chiropractic vertebral subluxation hypothesis proposes that vertebral misalignment cause illness, disease, or both. This hypothesis remains controversial." His objective was, "To briefly review and update experimental evidence concerning reflex effects of vertebral subluxations, particularly concerning peripheral nervous system responses to vertebral subluxations. Data source: Information was obtained from chiropractic or, scientific peer-reviewed literature concerning human or animal studies of neural responses to vertebral subluxation, vertebral displacement or movement, or both." He concluded, "Animal models suggest that vertebral displacements and putative vertebral subluxations may modulate activity in group I to IV afferent nerves. However, it is not clear whether these afferent nerves are modulated during normal day-to-day activities of living and, if so, what segmental or whole-body reflex effects they may have."

Conclusions: Monitoring mixed-nerve root discharges in response to spinal manipulative thrusts in vivo in human subjects undergoing lumbar surgery is feasible. Neurophysiologic responses appeared sensitive to the contact point and applied force vector of the spinal manipulative thrust. Further study of the neurophysiologic mechanisms of spinal manipulation in humans and animals is needed to more precisely identify the mechanisms and neural pathways involved.

Researchers at the Department of Physiology, University College London studied the effects of compression upon conduction in myelinated axons. Using pneumatic pressure of varying degrees on the sciatic nerves of frog specimens, the study supported the idea of nerve conduction failure as a result of compression.


Critiques

An area of debate among chiropractors is whether "vertebral subluxation" is a metaphysical concept (as posited in B. J. Palmer's philosophy of chiropractic) or a real phenomenon.

In an article on vertebral subluxation, the chiropractic authors wrote:

"Subluxation syndrome is a legitimate, potentially testable, theoretical construct for which there is little experimental evidence. Acceptable as hypothesis, the widespread assertion of the clinical meaningfulness of this notion brings ridicule from the scientific and health care communities and confusion within the chiropractic profession. We believe that an evidence-orientation among chiropractors requires that we distinguish between subluxation dogma vs. subluxation as the potential focus of clinical research. We lament efforts to generate unity within the profession through consensus statements concerning subluxation dogma, and believe that cultural authority will continue to elude us so long as we assert dogma as though it were validated clinical theory."

Since its inception, the concept of vertebral subluxation has been a source of definitional debate. Tedd Koren, DC offers this explanation as a possible cause of the confusion:

The vertebral subluxation cannot be precisely defined because it is an abstraction, an intellectual construct used by chiropractors, chiropractic researchers, educators and others to explain the success of the chiropractic adjustment.

This is not a unique state of affairs, abstract entities populate many branches of science...

Subluxations, genes, gravity, the ego and life are all heuristic devices, "useful fictions" that are used to explain phenomenon that are far larger than our understanding. We use them as long as they work for us and discard or limit their application when they become unwieldy or unable to account for new observations...

Critics of chiropractic have incorrectly assumed that chiropractic is based on the theory or principle that vertebral subluxations cause "pinched" nerves that cause disease. They have it backwards. Chiropractic is based on the success of the spinal adjustment. The theory attempting to explain the success of the adjustment (nerve impingement, disease, subluxations) followed its clinical discovery.

Examples of such erroneous criticisms based on this straw man argument abound in the medical literature. Some examples: "The teachers, research workers and practitioners of medicine reject the so-called principle on which chiropractic is based and correctly and bluntly label it a fraud and hoax on the human race." "The basis of chiropractic is completely unscientific." The theory on which chiropractic is based , namely that a "subluxation" of a spinal vertebra presses on a nerve interfering with the passage of energy down that nerve causing disease to organs supplied by that nerve, and that chiropractic "adjustments" can alleviate the pressure thereby treating or preventing such disease. There is no scientific evidence for the validity of this theory."

To be fair, statements by some chiropractors have tended to perpetuate this misunderstanding: "Pressure on nerves causes irritation and tension with deranged functions as a result."

When chiropractors declare that "pinched nerves" "nerve impingement" "spinal fixations" or others mechanisms of action explain how subluxations affect the person and how chiropractic works they are making the same mistake medical critics make - assuming chiropractic is based on theory. Mechanisms and theories are useful tools, but their limitations should always be kept in mind.

Other chiropractors have declared its unproven status as an area that needs reform:

"Some may suggest that chiropractors should promote themselves as the experts in "correcting vertebral subluxation." However, the scientific literature has failed to demonstrate the very existence of the subluxation. Until and unless sound research published in credible journals demonstrates the existence and reliable identification of vertebral subluxation, and vertebral subluxation is found to be an important public health problem, society at large will not care about its correction. Thus, "subluxation correction" alone is not a viable option for chiropractic's future."

References

  1. ^ WHO guidelines on basic training and safety in chiropractic, p. 4, including footnote
  2. ^ Campbell JB, Busse JW, Injeyan HS (2000). "Chiropractors and vaccination: a historical perspective". Pediatrics. 105 (4): e43. doi:10.1542/peds.105.4.e43. PMID 10742364. ... considered disease the result of spinal nerve dysfunction caused by misplaced (subluxated) vertebrae. Although rejected by medical science, this concept is still accepted by a minority of chiropractors.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  3. Keating, Joseph, Jr. (March 2003,). "Evaluating the quality of clinical practice guidelines". Journal of Manipulative and Physiological Therapeutics. 26 (3): 209–11. doi:10.1016/S0161-4754(02)54104-X. {{cite journal}}: |access-date= requires |url= (help); Check date values in: |date= (help)CS1 maint: extra punctuation (link) CS1 maint: multiple names: authors list (link)
  4. "ACA CMS Clinical Documentation Guidelines" (PDF). American Chiropractic Association. Retrieved 2008-05-06.
  5. Palmer DD (1910) The Science, Art and Philosophy of Chiropractic Portland, Oregon: Portland Printing House Company p20
  6. Joseph M. Flesia, Jr., D.C. The Vertebral Subluxation Complex: An Integrative Perspective. ICA International Review of Chiropractic 1992 (Mar): 25-27
  7. ^ Keating JC Jr, Charlton KH, Grod JP, Perle SM, Sikorski D, Winterstein JF (2005). "Subluxation: dogma or science?". Chiropr Osteopat. 13: 17. doi:10.1186/1746-1340-13-17. PMID 16092955.{{cite journal}}: CS1 maint: multiple names: authors list (link) CS1 maint: unflagged free DOI (link)
  8. World Chiropractic Alliance. Position paper on caring for asymptomatic patients
  9. BOOP. Spinal Injury Foundation
  10. Robert A. Leach. The chiropractic theories. Lippincott Williams & Wilkins, 2003, ISBN 0683307479, 9780683307474, 463 pages. Book search with numerous mentions of BOOP's history.
  11. Strang, V (1984) Essential Principles of Chiropractic Davenport : Palmer College of Chiropractic, OCLC: 12102972
  12. M.I. Gatterman, M.A., D.C. One Step Further: The Vertebral Subluxation Syndrome. Dynamic Chiropractic, March 27, 1992, Volume 10, Issue 07
  13. Cramer G, Fournier J, Henderson C, Wolcott C (2004). "Degenerative changes following spinal fixation in a small animal model". J Manipulative Physiol Ther. 27 (3): 141–54. doi:10.1016/j.jmpt.2003.12.025. PMID 15129196.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  14. ^ Seaman D, Winterstein J (1998). "Dysafferentation: a novel term to describe the neuropathophysiological effects of joint complex dysfunction. A look at likely mechanisms of symptom generation". J Manipulative Physiol Ther. 21 (4): 267–80. PMID 9608382.Full text online
  15. Nansel D, Szlazak M (1995). "Somatic dysfunction and the phenomenon of visceral disease simulation: a probable explanation for the apparent effectiveness of somatic therapy in patients presumed to be suffering from true visceral disease". J Manipulative Physiol Ther. 18 (6): 379–97. PMID 7595111.
  16. Hardy K, Pollard H. "The organisation of the stress response, and its relevance to chiropractors: a commentary." Chiropractic & Osteopathy 2006, 14:25doi:10.1186/1746-1340-14-25
  17. Budgell BS (2000). "Reflex effects of subluxation: the autonomic nervous system". J Manipulative Physiol Ther. 23 (2): 104–6. PMID 10714536. {{cite journal}}: Unknown parameter |month= ignored (help)
  18. Bolton P (2000). "Reflex effects of vertebral subluxations: the peripheral nervous system. An update". J Manipulative Physiol Ther. 23 (2): 101–3. doi:10.1016/S0161-4754(00)90075-7. PMID 10714535.
  19. Colloca C, Keller T, Gunzburg R, Vandeputte K, Fuhr A (2000). "Neurophysiologic response to intraoperative lumbosacral spinal manipulation". J Manipulative Physiol Ther. 23 (7): 447–57. doi:10.1067/mmt.2000.108822. PMID 11004648.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  20. Fern R, Harrison PJ (1991). "The effects of compression upon conduction in myelinated axons of the isolated frog sciatic nerve". J. Physiol. (Lond.). 432: 111–22. PMC 1181320. PMID 1886055. {{cite journal}}: Unknown parameter |month= ignored (help)
  21. Tedd Koren, D.C. "Does the Vertebral Subluxation Exist?" Used here by permission.
  22. Murphy, et al. "Bringing Chiropractic Into the Mainstream in the 21st Century - Part II", Dynamic Chiropractic, September 1, 2005, Vol. 23, Issue 18

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