1043_hannon_objphysiochanges-new.pmd

REVIEW OF THE LITERATURE
Objective Physiologic Changes and Associated Health Benefits of Chiropractic Adjustments in Asymptomatic ABSTRACT
documenting objectively measured health benefits in subjects Objective: To review existing literature documenting objec-
to which no symptomatic presentation was described.
tively measured physiologic changes and their associated health Conclusion: The data reviewed lend support to the contention
benefits subsequent to chiropractic adjustments, primarily in that chiropractic adjustments, often for the purpose of correct- ing vertebral subluxation, confer measurable health benefits to Data Collection: “Asymptomatic” “normal” “pain-free” and
people regardless of the presence or absence of symptoms. A “healthy” subjects were keywords used to search for articles significant amount of preliminary evidence supports that people pertaining to the objective. Data was collected directly from without symptoms can benefit from chiropractic care. Improved the bound journals of the Palmer College of Chiropractic li- function can be objectively measured in asymptomatic individu- brary in Davenport, IA, Life University library in Marietta, GA, als following chiropractic care in a number of body systems and the Sherman College of Chiropractic library in Spartanburg, often by relatively non-invasive means. It is plausible that chi- SC. Some articles were downloaded from peer-reviewed jour- ropractic care may be of benefit to every function of the body nals accessible through campus Internet subscription.
and have the potential for long-term, overall health benefit to Results: More than twenty studies were found documenting
objective health benefits in subjects who were specifically de-scribed as “asymptomatic,” “healthy,” “normal,” or “free from Key words: chiropractic adjustment, subluxation, objective
physical injury.” Nearly an equal number of studies were found Introduction
“I try to encourage my patients who are open to continue maintenance A recent survey of 658 randomly selected US chiropractors care… However, I have yet to see a single research finding that indi- revealed some surprising data.1 Eighty-eight percent (88.3%) cates that those patients who do receive regular chiropractic care, re- of respondents agreed or strongly agreed that the purpose of gardless of symptomotology, benefit in any measurable way.”-Scott Rogers, MA,DC maintenance care was “to maintain or optimize state of health.”Eighty-percent (80.2%) of respondents agreed or strongly agreed Others have expressed their opinions on the subject in peer- that the purpose of maintenance care was to “determine and treat subluxation.” Furthermore, US chiropractors agreed that“maintenance care was of value to all age groups, with the value “Many chiropractors will continue to adjust imaginary subluxations in increasing slightly with an increase in a patient’s age.” How- the spines of perfectly healthy patients, perpetuating unsubstantiated ever, only forty-percent (40.2%) agreed that “adequate research claims and discouraging chiropractors who wish to specialize in the treat- existed to support the concept of maintenance care,” and ninety- ment of neck and back pain…2 Chiropractors who believe that vertebralalignment has something to do with general health often encourage their three percent (93.4%) agreed “there was a need for more re- patients to submit to regular and frequent manipulation, even when these search.” It seems that US chiropractors agree and are of the patients are asymptomatic… I cannot personally justify manipulating opinion that correcting subluxation is of value to all people, but the spine of a healthy, symptom-free patient… It is unfair to patients to nearly 60% do not think there is sufficient evidence to verify allow them to believe that they must have regular spinal adjustments inorder to stay healthy… I cannot see any basis or justification for rou- their opinion. One chiropractor expressed this frustration in a tinely manipulating the spine of a healthy patient for the purpose of Letter to the Editor in the August 6, 2000 issue of Dynamic maintaining health or preventing disease.”3 Chiropractic, a trade journal of the chiropractic profession: Sean M. Hannon, BA, DC, Private Practice, Denver, CO Objective Physiologic Changes and Health Benefits of Chiropractic Adjustments J. Vertebral Subluxation Res. - JVSR.Com, April 26, 2004 1 Many in the chiropractic profession, often from seemingly ies to which objective, physiologic changes following chiro- different political camps, contend that chiropractic care is ben- eficial to people regardless of one’s symptomatic presentation.4 Much of the data reviewed here have been reviewed before.
However, what makes this review unique is that these data are “Straight chiropractic consists solely of the philosophy, science and art reviewed not so much in terms of what factors were measured, of locating, analyzing and assisting in the correction of vertebral sub- but who were these factors being measured in. Since this re- luxation because they are detrimental to the expression of innate intel-ligence.” view focuses on objectively measured physiologic changes and - Definition of Straight Chiropractic according to The Federation of their associated health benefits primarily in “asymptomatic” Straight Chiropractors & Organizations subjects, the phenomenon of pain will not be addressed, de-spite the numerous studies documenting pain resolution fol- “…pain may not be the symptomatic outcome of nociceptive stimula- lowing chiropractic care. Furthermore, for the purpose of con- tion of spinal structures. Such a conclusion has profound implicationsfor the chiropractic profession. Clearly, patients do not need to be in sistent terminology and reader simplicity terms such as sublux- pain to be candidates for spinal adjustments.”5 ation, vertebral subluxation complex, segmental dysfunction, - David Seaman, DC & James Winterstein, DC (President of National joint complex dysfunction, manipulable lesion, or spinal fixa- tion will be collectively referred to as “vertebral subluxation” This paper seeks to address this controversial issue and lend or “subluxation.” Similarly, adjustment, adjustive thrust, spinal scientific validation to such a philosophical perspective by re- manipulative therapy (SMT), HVLA manipulation, etc. will viewing existing peer-reviewed literature.
collectively be referred to as “adjustment” or “chiropractic ad- Within the last several years there has been a tremendous interest in and focus on subjective measurements of chiroprac- Part I: Objective Physiologic Changes in Asymptomatic
tic care as it relates to overall health and wellness. Numerous Subjects
studies have documented the subjective, self-rated assessments There is an increasing body of evidence suggesting that the of chiropractic care on overall health, quality of life, and correction of subluxation through chiropractic adjustments im- wellness.6 7 8 9 10 11 50 Many of the studies involve adequate popu- prove physical functioning and health regardless of the pres- lations and have well-constructed methodologies. However, ence or absence of symptoms or pathology. The studies sum- while self-rated surveys such as the RAND (SF-36) Health marized below document these objective physiologic changes Survey, the Global Well-Being Scale (GWBS), and the Self- Rated Health/Wellness Survey (SRHW) are accepted forms of Nansel et al. 12,13,14 conducted several controlled, blinded stud- scientific measure, they are still often considered inferior to ies in 1989, 1991, and 1992 to assess the effect of unilateral more objective measurements in the hierarchy of scientific spinal adjustments on end range asymmetries in “asymptom- methodology. The intent of this paper is to illustrate the objec- atic” subjects. Results demonstrated that cervical adjustments tively measured physiologic changes and their associated health ameliorated the lateral flexion asymmetries in the cervical spine.
benefit following the administration of chiropractic adjustments.
No statistically significant changes were found in control sub- Particular attention has been given to identifying those stud- jects. The vast amount of data regarding the physiologic conse- ies that were conducted on reportedly “healthy,” “normal,” or quences of a loss of range of motion (ROM) and tissue atrophy otherwise, “asymptomatic” individuals. This has been done to associated with immobilization is ample justification to recog- illustrate that the correction of subluxation can be demonstrated nize an improvement in ROM as a health benefit or contribu- to have both short- and long-term health benefits for individu- tion to improved function. The 1991 study also monitored als beyond that of back and neck pain relief. Furthermore, some changes in blood pressure, heart rate, and plasma catechola- studies reviewed here suggest that health benefits accrue re- mine levels, but failed to show any statistically significant gardless of the presence or absence of disease, infirmity, or the In 1993, Nansel et al.15 conducted a randomized, double- Review Design
blind study again involving sixty-eight “healthy, non-symptom- This paper has three parts. Part I will review literature that atic” subjects. Results indicated that cervical adjustments have documents objective, physiologic changes following chiroprac- significant effects on the tone of the lumbopelvic musculature tic care in asymptomatic individuals. Part II will review litera- by facilitating tonic neck reflexes involving intersegmental path- ture that documents objective, physiologic changes following ways. Interestingly, lower cervical adjustments had a more pro- chiropractic care in subjects to which there is no mention of found effect, a decrease in tone, on lumbopelvic musculature symptoms or pathology. This could mean that the individuals than upper cervical adjustments. In 1998, Pollard & Ward16 involved in these studies may (or may not) have been asymp- documented a similar link between the cervical spine and range tomatic. The studies in Part II are of particular interest because the lack of a symptomatic description of the subjects involved Pollard & Ward17, in 1996, report a progressive, short-term lends credence to the notion that symptomatic presentation is increase in strength of the quadriceps femoris in 15 subjects not necessarily relevant to the administration of chiropractic following a single chiropractic adjustment to the L /L motion care. Part III reviews a minority of the literature involving in- segment in the side posture position. Subjects were described dividuals who presented with symptoms or pathology. Part III as “healthy, asymptomatic students” with “no history of recently is of value to this discussion because it further documents stud- diagnosed lumbar disc herniation, sprain, or other lumbar in-
Objective Physiologic Changes and Health Benefits of Chiropractic Adjustments J. Vertebral Subluxation Res. - JVSR.Com, April 26, 2004 jury.” The control group demonstrated a progressive strength to the chiropractic adjustments were not observed in those sham- decrease following a sham adjustment. The overall change be- adjustments. More recently, Whelan et al.23 came to a similar tween the two groups was statistically significant. Bonci & conclusion using pre/post salivary cortisol levels as a measure Ratliff,18 in 1990, failed to demonstrate statistically significant of stress levels associated with chiropractic adjustments.
changes in biceps strength following a chiropractic adjustment Vernon et al.24 demonstrated a small, but statistically signifi- to the mid-cervical region in “healthy” subjects.
cant increase in serum beta-endorphin levels in a randomly se- Symons et al19. were able to detect and measure reflex re- lected group of “normal male subjects” following a single chi- sponses via surface EMG 68% of the time following chiroprac- ropractic adjustment to the cervical spine. Both the sham ad- tic adjustments in nine “healthy, asymptomatic volunteers.” The justment and control groups demonstrated a steady decrease in reflex response originating from the muscle spindles is theo- serum beta-endorphin levels. Though these findings are very rized to be an underlying mechanism explaining the success of intriguing, others have failed to produce similar findings of sta- chiropractic care for people presenting with numerous symp- tomatic presentations. The Symons study also demonstrated that Tran & Kirby26 studied the effects of upper cervical chiro- reflex responses were least often detected in the cervical spine practic adjustments upon the physiology of the heart in twenty and were progressively more often detected caudally down the “normal and healthy” individuals. Seventeen of twenty (85%) subjects presented as “normotensive.” The most significant pre- McGregor et al.20 studied immunological responses to twenty and post- adjustment changes were a decrease in pulse pressure “normal” subjects following an adjustment to the lumbar spine and an increase in diastolic pressure, which occurred in the or a sham adjustment to the gluteal musculature. Results dem- onstrate a statistically significant increase in respiratory burst McKnight & DeBoer27 measured the impact of chiropractic measured by the chemoluminescence response suggesting adjustment on seventy-five male and female subjects predeter- stimulation of the immune system. The sham adjustment con- mined to have “normotensive” blood pressure. All subjects were trols did not demonstrate evidence of enhanced respiratory burst “in good physical health with no reported underlying cardio- vascular disorders or other relevant pathologies.” Subjects re- Brennan and Kokjohn et al.21 studied the effects of chiro- ported not ingesting prescription medication or caffeine prior practic care on the immune systems of forty-two “healthy adult to blood pressure testing. Those determined to have cervical volunteers” compared to thirty-eight sham adjustment subjects.
subluxations were included in the experimental group. Those It was found that the chemoluminescent responses of polymor- remaining were controls. Statistically significant changes in phonuclear neutrophils (PMNs) and monocytes of those sub- blood pressure were observed following chiropractic adjust- jects receiving a chiropractic adjustment to the thoracic spine ment though changes were not considered “clinically” signifi- were significantly higher than initial values and significantly higher than the response in the sham adjustment group. This Gibbons et al.28 studied thirteen “healthy male subjects… study demonstrated that chiropractic adjustments elicit without a history of eye disease of central or autonomic ner- viscerosomatic responses. Specifically, this study demonstrated vous system pathologic conditions.” They demonstrated that that chiropractic adjustments effect cells involved in immune upper cervical adjustment can produce a significant, measur- able increase in speed of the autonomically mediated edge light Brennan and Triano et al.22 expanded their previous work.
pupillary cycle time (ELPCT), that is, a decrease in the time it Forty-six “asymptomatic subjects” consisting of “healthy adult takes to complete constriction and redilation of the pupil when volunteers” were used for this study of chiropractic care’s ef- exposed to light. These findings suggest an interrelation be- fect on the immune system. This study confirmed their previ- tween somatic and autonomic function and therefore, a more ous report that a chiropractic adjustment to the thoracic spine diverse effect on cortical function.
primes the PMN for an enhanced respiratory burst, and primes Zhang29 measured the effect of chiropractic care on the au- mononuclear cells for enhanced endotoxin-stimulated tumor tonomic nervous systems of twenty-six “normal” volunteers necrosis factor (TNF) production. Significantly elevated levels measured by way of Heart Rate Variability (HRV), of the undecapeptide neuroimmunomodulator substance P, ac- subcategorized as Low Frequency (LF), a measure of sympa- companied these priming effects, at least for the short-term.
thetic activity, and High Frequency (HF), associated with para- Asymptomatic sham adjustment subjects did not show such sympathetic activity. After one year of chiropractic care the LF/ HF ratio changed significantly indicating an increased para- Some critics have suggested that the findings of these last 3 sympathetic stimulation, which is associated with a slower heart studies summarized above merely demonstrate the body’s im- rate and less anxiety and worry. Zhang notes that this finding is mune response to trauma and that any form of stimulation ap- significant because a reduced heart rate can potentially reduce plied to the skin might produce an increase in activity of white heart attack and other cardiovascular diseases by increasing cells such as “a couple of whacks with a paddle.”2 This sugges- cardiac reserve and nutrient supply to cardiac muscles.
tion is unfounded, in that both the McGregor study and the Miller et al.30 studied several variables related to endurance Brennan studies did have adequate sham-adjustment controls or cardiac and pulmonary physiology in nine “healthy, active” involving significant stimulation of the skin. McGregor stated volunteers following chiropractic adjustment to the cervical and that immune responses were specific to an application of force thoracic spine. The chiropractic group demonstrated a 6.1% directed at the spinal joints and that immune responses similar increase in Maximal Aerobic Capacity (VO2 max), a 3.9% in- Objective Physiologic Changes and Health Benefits of Chiropractic Adjustments J. Vertebral Subluxation Res. - JVSR.Com, April 26, 2004 crease in Overall Work (Power Output), a 2.6% increase in Peak Schwartzbauer et al.36 demonstrated significant improvement Heart Rate and peak systolic blood pressure. Neither control in the performance of twenty-one male college “athletes” who nor secondary intervention (soft tissue massage) subjects dem- were “free from physical injury.” After fourteen weeks of chi- onstrated such changes. However, these findings were not con- ropractic care the athletes showed significant improvement in sidered statistically significant in terms of endurance.
muscle strength, long jump distance, and capillary counts.
Menon et al.31 studied the effect of thoracic spinal adjust- Briggs and Boone37 measured autonomic response monitored ment on the peripheral airway function of twenty-two “normal, as a change in pupillary diameter in eight subluxated subjects.
asymptomatic” subjects. Using dry spirometry, Forced Expira- Though not specifically described as “asymptomatic,” all sub- tory Flow Rate (FEF) was measured as an indicator of airway jects were “screened by a licensed optometrist… (for) visual function. Paired t-tests were performed between pre- and post- acuity of 20/20, an accommodative convergence / accommo- measurements. FEF values showed a significant post-interven- dative ratio of 5 or less, and an accommodative system free of pathology.” This was considered specific-function “normal,” Masarsky & Weber32 report on the lung volumes of 50 pa- and therefore was included in Part I of this review. Eight out of tients. Although most subjects presented with musculoskeletal eight (100%) subluxated subjects demonstrated a 50% or greater complaints, 43 of 50 (86%) subjects were essentially “lung- change in variables following a single adjustment to the upper normal” in FVC by spirometric criteria and therefore have been cervical spine. Six of seven sham-adjusted subjects acting as included in the asymptomatic section of this paper. Improved controls demonstrated no such change between pre- and post- FVC values were noted in 35 of these 43 “lung-normal” sub- analysis. The authors conclude that autonomic somato-visceral jects. Results were significant at the .01 level. Improved FEV- reflexes of a non-specific nature can be elicited following a 1 values were also observed in 29 subjects and were significant chiropractic adjustment. They also stated, “it appears that the at the .05 level. The authors specifically stated that it was of efficacy of the chiropractic adjustment rests in the removal of particular interest to observe the improved lung volumes in a sublxuation as opposed to being a treatment entity for specific group of essentially “lung-healthy” patients.
symptoms associated with visceral organ systems.” Kessinger33 measured changes in pulmonary function asso- ciated with upper cervical chiropractic adjustments on 55 sub- Part II: Objective Physiologic Changes in Subjects
jects. Twenty-two of 55 (40%) were “typical” subjects, that is, without Mention of Symptomatic Presentation
they presented within “normal” range of Forced Vital Capacity Additional studies measure physiologic improvement fol- (FVC) values. Following two weeks of chiropractic care 73% lowing chiropractic care but make no mention to symptoms or of these “typical,” normal range subjects further improved FVC pathology of subjects involved. The primary focus of these stud- values by 6%. Thirty of 55 (55%) were “typical” subjects, that ies was, again, to demonstrate the objective physiologic changes is they demonstrated a normal range of Forced Expiratory Vol- of chiropractic adjustment and any subsequent health benefit.
ume per 1 second (FEV-1). Following two weeks of chiroprac- Kessinger and Boneva38 demonstrated significant improve- tic care approximately 47% of these “typical,” normal range ments in neurocognitive function in 30 subjects receiving 4 subjects further improved FEV-1 values by 6%. Overall results weeks of upper cervical care compared to 10 control subjects of the study indicated that pulmonary function improves sig- who did not demonstrate a similar trend. Cognitive function nificantly in subjects under upper cervical chiropractic care.
was measured via the computer administered and scored test, Goff, McConnell, & Paone34 explored the relaxation response Microcog. This program scores attention/mental control, as it relates to the correction of subluxation via chiropractic memory, reasoning/calculation, spatial processing, reaction time, adjustment. The relaxation response was measured through information processing speed, information processing accuracy, EMG potentials, spinal ROMs, and anxiety levels. Twenty-six general cognitive functioning, and general cognitive proficiency.
adults determined to have a subluxation, “but not having a di- Kelly, Murphy, and Backhouse39 utilized a mental rotation agnosis of other clinically significant disorders” were used.
reaction-time paradigm to assess changes in cortical process- Results indicated a significant change occurred in the chiro- ing following chiropractic adjustments. Thirty-eight volunteers practic group as compared to the 23 controls. Adjustments fa- were tested in this study. The average decrease (improvement) cilitated a considerable decrease in patient muscle tension.
in reaction time for the experimental group was 14.9%. The Lauro & Mouch35 measured changes in agility, balance, ki- control group improvement of only 8% was attributed to a learn- nesthetic perception, power, and speed reaction in twenty-four ing curve effect. The study demonstrated a small but statisti- “asymptomatic” athletes “with no acute or chronic debilitating cally significant improvement in cognitive function after a single injuries.” Athletic performance in these five categories was measured at six and twelve weeks of chiropractic care and were Carrick40 conducted a double blind study involving 500 sub- compared to twenty-two control athletes. Results of the first jects enrolled in a postdoctoral neurology program, which dem- six weeks revealed a 10.57% improvement in the chiropractic onstrated, by way of visual field blind spot analysis, that ad- group and only a 4.5% improvement for controls. The twelve- justment activates specific neurological pathways associated week evaluation demonstrated further improvement of 16.7%.
with cortical hemisphericity. Carrick stated that the clinical re- The authors stated that the data supports that “the correction of sults attributed to upper cervical spinal adjustment occur as a the subluxation complex enables the body to function and per- consequence of the integration of variables that sum to pro- mote human brain function. He also notes that the benefits of Objective Physiologic Changes and Health Benefits of Chiropractic Adjustments J. Vertebral Subluxation Res. - JVSR.Com, April 26, 2004 chiropractic adjustment may not be limited to musculoskeletal sternal, Left pectoralis major clavicular, L&R anterior deltoid, L&R Latismus dorsi, L&R psoas, L&R tensor fascia lata, L&R Waters & Boone41 investigated whether or not the presence adductor muscle, and L&R gluteus medius. The results of this of subluxation indicators such as leg imbalance, pelvic distor- study suggest that the chiropractic SOT pelvic blocking proce- tion, and cervical syndrome would have any possible correla- dure produced a general increase in muscle strength.
tion with a poorer performance of fourteen “female dancers.” Rebechini-Zasadny et al.46 noted significant increases in the The dancers were first examined for the presence or absence of strength of the first dorsal interosseous muscle during isomet- the subluxation indicators, performed their dance routines, and ric contraction following chiropractic adjustments to the cervi- then were asked to self-rate their own performances. It was found cal spine. The twelve volunteers involved were measured using that the presence of indicators associated with subluxation were EMG. Improvement in finger muscle strength following adjust- negatively associated with the overall dance performance rela- ment to the cervical spine demonstrates how chiropractic ad- tive to muscle balance. Overall dance performance was rated justments can have benefit distal to the locality of adjustment.
high in individuals exhibiting no spinal misalignment elements Coulter et al.47 assessed the characteristics of older people and lower in individuals exhibiting spinal misalignment ele- who utilize chiropractic care. Of a total sample size of 414 se- ments. Even though the dancers subjectively self-rated their own niors, 23 were called “chiropractic users.” Coulter found that performances, the dancers were blinded to the presence or ab- senior citizen chiropractic users were more likely to report sence of subluxation indicators prior to performing the dance strenuous levels of exercise, and more likely to report leaving routine. Therefore, the results of this study were included in their neighborhood in good weather five or more time per week.
Chiropractic users were also less likely to report their health Kessinger and Boneva42 measured visual acuity in 67 sub- status as “fair” or “poor” and were less likely to report having jects (who had not been under previous chiropractic care) fol- arthritis than non-chiropractic users. A non-significant trend for lowing six weeks of upper cervical chiropractic care. Statisti- chiropractic users to report fewer depressive symptoms was also cally significant improvements for the whole population were observed. Furthermore, chiropractic users were less likely to demonstrated in the right eye at distances associated with less have used a nursing home, and 73.9% of chiropractic users had than “typical” normal vision, and better than “typical” normal not been hospitalized in 3 years. Lastly, chiropractic users were vision. Significant improvements were also shown for the left associated with a tendency to use less over-the-counter (OTC) eye at the same distance acuity levels, as well as additional lev- and prescription medications than those not using chiropractic els. Kessinger concluded that vision changes do occur follow- care. Coulter was careful to state that these findings were only ing upper cervical chiropractic adjustments.
associated with chiropractic use and that it may not constitute a Harris and Wagnon43 studied the effects of chiropractic ad- causal relationship with chiropractic care. These observations, justments on distal skin temperatures in 196 subjects. Their work while neither objective nor specifically physiological, do sug- clearly demonstrated that chiropractic adjustments significantly gest the possible long-term health benefits of chiropractic utili- affect temperature in tissues distant from the spine and that these zation regardless of the presence or absence of symptoms.
changes will vary depending upon which area of the spine is A study by Rupert48 involving 311 senior citizens under chi- adjusted. Approximately 84% of adjustments given in the C - ropractic “maintenance care” produced some rather dramatic C area and/or L -L area inhibited sympathetic nervous system and significant results. While some chiropractors in this study outflow (a temperature increase), while adjustments in the T - also provided recommendations pertaining to exercise, nutri- L region stimulated the SNS (a temperature decrease) 67% of tion, and relaxation, seventy-three percent (73%) of chiroprac- the time. These findings suggest a regulatory effect of chiro- tors reported that maintenance care was being given to their practic adjustments and, therefore, are significant because the patients to prevent or control subluxation. Those seniors using purpose of the vast majority of blood flow in this tissue is to maintenance care made approximately half the number of vis- regulate temperature, an important aspect of maintaining proper its to a medical provider compared to the national average. The study also found a significant correlation between the reduced Tuchin44 measured the effects of chiropractic adjustment on use of non-prescription drugs and the number of years of main- salivary cortisol levels in nine subjects. Pre- and post- adjust- tenance care, that is, the longer one was under maintenance ment data revealed a statistically significant reduction of sali- care the less likely they are to use non-prescription drugs. Only vary cortisol over the 5-week study. These findings are signifi- 36% of patients reported frequent use of non-prescription drugs.
cant because salivary cortisol levels closely reflect serum corti- Furthermore, the annual health care cost for US senior citizens sol levels. Elevated serum levels of cortisol have been associ- in 1994 was conservatively estimated at $10,041.00 per per- ated with disturbed concentration, tremors, elevated heart rate son. The annual health care cost associated with those under chiropractic maintenance care was $3,106.00 per person. This Unger45 recognized that muscle strength is a reflection of represents an annual cost less than 2/3 that of the national aver- neurological function. Sixteen patients underwent a course of age among chiropractic recipients. The authors state that those chiropractic pelvic blocking of the Sacro-occipital Technique patients receiving maintenance care required far less medical (SOT) protocol. Using a dynamometer, measurements of muscle intervention. Like Coulter’s study, these data are also strongly strength were assessed before and immediately after the chiro- suggestive of the possible long-term health benefits associated practic adjustments. There was a significant difference in muscle strength noted in the Left and Right (L&R) pectoralis major Objective Physiologic Changes and Health Benefits of Chiropractic Adjustments J. Vertebral Subluxation Res. - JVSR.Com, April 26, 2004 While some of the data from the Coulter and Rupert studies Childs, Freerksen and Plourde55 studied the possible effects could be considered subjective, (i.e. patient “reports”) it was of regular chiropractic care to changes in lipid metabolism in included because of the relevance to the intent of this review as ten randomly selected subjects exposed to a stressful environ- ment. This retrospective study assessed lab values over a pe-riod of one to three years. The same laboratory, personnel, in- Part III: Objective Physiologic Changes in Subjects
strumentation, and methods were used for all lipid tests over Presenting with Symptoms or Pathology
the three-year period. Results showed the Total Cholesterol (TC) Hundreds of articles document objective physiologic changes and Low Density Lipid (LDL) levels decrease in 70% of sub- in subjects presenting with symptoms or pathology. Here, a jects. Sixty-six (66%) percent of subjects classified as “border- handful of studies documenting such changes is discussed.
line high to high risk” for TC fell to desirable range following Allen reviews a study by Alcorn49 documenting increases in regular chiropractic care. Eighty (80%) percent of subjects ini- immunoglobulins IgA, IgG, and IgM in 3 out of 4 subjects (75%) tially classified as “borderline high to high risk” for LDL fell to following two-weeks of chiropractic care. Immunoglobulins desirable levels following regular chiropractic care. Fifty (50%) increased concurrently with the subjective improvement in the percent of subjects attained optimal range for Cardiac Risk Fac- subjects’ neuromusculoskeletal conditions. Other studies in tors and in 90% of subjects, Triglyceride levels dropped while humans and animals have correlated immune function with under regular chiropractic care. This study demonstrated a ten- neuromusculoskeletal conditions.50,51 Vora and Bates52 showed tative correlation between regular chiropractic care and improve- a significant increase in circulating B-lymphocytes in 5 of 8 ment of the blood lipid levels. The correlation established is of patients (63%) with radiographically proven significance since it is widely accepted that blood lipid levels neuromusculoskeletal conditions following 4 weeks (eight ses- are excellent in assessing the risk associated with premature sions) of chiropractic adjustments. Although the authors of the study arbitrarily assigned a 50% change in B lymphocyte val- Yates et al.56 conducted a randomized, controlled trial ex- ues to be significant, all 5 patients demonstrated a statistically amining the effects of upper thoracic chiropractic adjustments significant increase well over 100% of their initial value. One on blood pressure in twenty-one subjects with elevated blood of the 5 patients demonstrated over a 200% increase in circu- pressure. Only subjects demonstrated to have thoracic verte- lating B-lymphocytes. Two patients showed a decrease that was bral subluxations were randomly assigned to one of three groups: statistically insignificant, and the remaining patient showed no active, placebo, or control. Subjects in the active group showed significant change. Similarly, Selano et al.53 measured the CD4 statistically significantly decreases in both systolic and dias- cell counts in five HIV+ subjects receiving six months of upper tolic blood pressure. Placebo and control groups demonstrated cervical chiropractic care. These subjects were compared to 5 no such changes and did not differ significantly from each other.
HIV+ controls that received sham adjustments for six months.
Results support that adjustment of thoracic subluxation signifi- All 5 patients’ CD4 cell counts in the adjusted group increased, cantly reduces blood pressure of patients with elevated blood two of which increased by more than 125% each. This accounted for an overall increase of 48% in the adjusted group over the Jarmel and Zatkin57 demonstrated improvement of cardiac six-month period. Conversely, 4 of 5 patients in the sham ad- autonomic regulation following chiropractic adjustments in justment group’s CD4 values decreased, demonstrating a 7.96% eleven subjects presenting with dysrhythmic abnormalities.
overall decrease in CD4 cell counts. The authors concluded that Following one month of chiropractic care, a positive trend in chiropractic adjustments of the upper cervical spine may in- the number of ventricular beats, ischemic events, maximum time crease the CD4 levels in HIV+ individuals. While the findings of ST segment depression, elimination of after-depolarizations, of the Acorn, Vora & Bates, and Selano studies are interesting and enhanced heart rate variability was observed. Findings were and warrant further investigation, the populations are far too small to draw any general conclusions independently, however Lott et al.58 showed that chiropractic adjustments to some when viewed collectively, they appear more significant.
extent bring about improved cardiac function. Lott described Kokjohn et al.54 randomly assigned 24 women into an ex- four case studies of patients presenting with cardiac dysfunc- perimental group and 21 women into a control/sham group. All tion as monitored by ECG. Patients received osseous chiropractic women had a history of primary dysmenorrhea. The experi- adjustments (and diet/exercise recommendations) over a time mental group received chiropractic adjustments to all clinically period ranging from 5 to 16 months. Improvements in ECG relevant vertebral levels within T10 and L5-S1, and the sacro- recordings were seen in all four cases. Significant improvements iliac joints. Plasma levels of KDPGF were used as a measure- were seen in three of four subjects as indicated on ECG by the ment because plasma concentrations of this metabolite are sig- CompuMed rating system. Two subjects had significant reduc- nificantly higher in dysmenorrheic women than eumenorrheic tions in blood pressure and pulse rate and one subject showed women. Samples were collected pre- and post-adjustment in probable elimination of ischemia in the myocardium.
both the experimental and control/sham group. Results showed Dickinson59 studied 31 diabetic volunteers receiving chiro- a significant reduction in plasma levels of KDPGF in the ad- practic spinal adjustments and interferential therapy. Volunteers justed group. The control/sham group also demonstrated a sig- were measured using the Imex 301 Doppler Ultrasound Trac- nificant reduction; however, pain and menstrual distress reduc- ings multiple times over the course of the 5-week study. Twenty- tions were nearly twice as great in the chiropractic group.
seven of 31 volunteers (87%) demonstrated increased circula-tion. No measurable changes were observed in 3 volunteers.
Objective Physiologic Changes and Health Benefits of Chiropractic Adjustments J. Vertebral Subluxation Res. - JVSR.Com, April 26, 2004 Dramatic subjective improvement was also noted in nearly all thermore, muscle inhibition was decreased in both legs follow- volunteers. It is difficult to determine if the chiropractic adjust- ing adjustments for patients with bilateral anterior knee pain.
ments or the interferential therapy most contributed to the re- Fallon65 investigated the relationship of labor time as a func- sults of this study. However, some literature suggests that inter- tion of chiropractic care versus non-chiropractic care. The la- ferential therapy is of little or no value.60 This may lend more bor times of sixty-five women who had received chiropractic support to the notion that chiropractic adjustments were the criti- care from at least the 10th week of pregnancy through labor and delivery were compared to statistically averaged mean labor Although Kessinger31 demonstrated significant improvement times. Chiropractic users were found to have significantly re- in pulmonary function in those subjects with “typical, normal” duced labor times of 24% and 39% for primigravidae and mul- Forced Vital Capacity (FVC) and Forced Expiratory Volume tiparous pregnancies, respectively. Fallon concluded that chi- per 1 second (FEV-1) values, the 33 (60%) subjects presenting ropractic can significantly reduce mean labor time.
“outside the normal range” showed the greatest increases in Conclusion
FVC and FEV-1. Thirty-one of the 33 “atypical” subjects (93%) Data reviewed in this article lend strong support to the popular showed an increase in FVC nearly half of which were now within contention that chiropractic adjustments, for the purpose of “normal” FVC range. Of the 25 subjects (45%) presenting out- correcting subluxations, confer health benefits to people regard- side the “normal” range of ideal FEV-1 values, 21 (84%) showed less of the presence or absence of symptoms. While each and an increase in FEV-1 after the two week period of chiropractic every one of the studies reviewed here may have inherent weak- care. Nearly a third of which were now within “normal” FEV-1 nesses and limitations in its design and/or conclusions, the data still can be viewed and interpreted collectively. The notion that Two medical doctors, Pikalov and Kharin61 demonstrated that there is no evidence of chiropractic care being of benefit to the use of chiropractic adjustments for the treatment of 11 adults individuals without musculoskeletal complaints appears erro- with duodenal ulcers experienced clinical remission an aver- neous. Improved function can be measured in “normal” pre- age of 10 days earlier than 24 control subjects receiving tradi- senting individuals following chiropractic care. Objective physi- tional medical care for the same condition. Remission was con- ologic changes and their associated health benefits can be eas- firmed with endoscopy. These medical doctors concluded, “fur- ily measured in a number of body systems, often by relatively ther investigation is necessary to search for optimal conditions non-invasive means. The data presented here are of varying and correlation with vertebral correction.” methodologies; several studies are controlled trials, some with Jarski et al.62 conducted a single-blinded, match-controlled randomization (RCTs) and some with single and double blind- outcome study involving 38 post-operative subjects receiving ing. Others are retrospective studies, pilot studies, and still some osteopathic manipulation of the lower extremities, (similar to chiropractic adjustments) during a rehabilitation program. A This review collectively documents statistically significant control group of 38 post-operative subjects undergoing the same improvements in respiration, range of motion, heart rate vari- rehabilitation program was also monitored. The group receiv- ability and autonomic function, endocrine function, cardiovas- ing osteopathic manipulation negotiated stairs 20% earlier and cular function, immune function, muscle strength and overall ambulated further on post-operative days 1-4 than did the con- athletic ability of “healthy” or specific-function “normal” indi- trol group. Additionally, the experimental group also required viduals. Other studies have documented statistically significant less pain medication and shorter hospital stays.
increases or improvements in neurocognitive functions such as Sixteen female distance runners presenting with sacroiliac reaction-time and information processing, visual acuity, stress subluxation were assessed by Grimston et al.63 Subjects under- and reproductive hormones, healing / recovery time, general went 12 sessions of chiropractic adjustment (in conjunction with health of senior citizens, and reduced labor times of pregnant muscular rehabilitation) over a 4-week period. Compared to women following or during chiropractic care.
four control subjects, a statistically significant decrease in Considering that these initial findings document objectively lumbo-pelvic asymmetry was observed. Following care, all 12 measured physiologic changes and their associated health ben- subjects with sacroiliac subluxation had reinstated their preinjury efits in nearly every major system of the human body, it is plau- training mileage. Five of twelve subjects (» 40%) reported their sible that chiropractic care may benefit every function of the personal best performance over the 10-kilometer distance run.
body. Furthermore, these data are congruent with numerous Two subjects achieved personal best times over the marathon subjective studies that suggest chiropractic care is associated distance (42-kilometer). All (100%) subjects reported enhanced with accruing, long-term, overall health benefits. The author of awareness of posture and flexibility in addition to reduced symp- this review agrees that while it is the opinion of an overwhelm- ing majority of practicing doctors of chiropractic that regular Suter et al.64 studied the effects of sacroiliac spinal adjust- chiropractic care is of benefit to all people of all ages, more ments on 18 patients presenting with anterior knee pain. Torque, research is necessary to further document the efficacy of sub- muscle inhibition and muscle activation for the knee extensor muscles were measured using a Cybex dynamometer beforeand after chiropractic adjustments. Increases in knee extensor References:
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