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January 2005, Vol. 15, No. 1
Table of Contents
ACA's New CCGPP Guidelines • An Opinion of Shortcomings CBP® • ASHN: Chiropractic Enemy • CBP® fosters international Research Collaboration • CBP® Research Corner • Contraction/Expansion Mentally • COX Inhibitors and the FDA • Counter Point • Do You Practice CBP®? • Don's Opinion • European Spine Accepts CBP® Clinical Control Trial • Regarding the Use of Body Weighting • SAC Reaffirms Life University's Accreditation • Spine Accepts CBP® Research • The Diminishing Return Triangle • Traction Details • Validity of PosturePrint™
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Counter Point:
A Selective Literature Review, Misrepresentation of Studies, and Side Stepping Spine Biomechanics Lead to an Inappropriate Characterization of CBP® Technique
by Deed E. Harrison, DC
After his undergraduate pre-chiropractic courses at the University of Utah, Dr. Deed Harrison graduated from Life-West in 1996. He is co-author of more than 50 peer-reviewed, indexed, research articles. These include 32 in JMPT, 3 in Chiropractic Technique, and 15 at major Index Medicus journals. He is a Reviewer for an Index Medicus Orthopaedic journal. He is a certified instructor for CBP® Seminars, has written three new CBP® text books, and is Vice-President of CBP® Nonprofit, Inc. He has a private practice in Elko, Nevada.
I would like to thank Dr. McDaniel for moving this debate from the California Chiropractic Associations (CCA’s) chat room discussion forum to the American Journal of Clinical Chiropractic (AJCC) enabling the profession at large to participate. Furthermore, I would like to thank him for his compliments regarding our research track record. However, I note that he took CBP® Technique in approximately 1985, and CBP® has evolved greatly since then. I have itemized Dr. McDaniel’s criticisms into ten points and provide a rebuttal to each below.
•A significant mischaracterization of the Harrison/Janik Spinal model
Dr. McDaniel repeatedly states the CBP® model is an ideal model of the sagittal plane curves. In reality, the Harrison/Janik sagittal model consists of two parts:
1) Ideal geometric model of each spinal region with total and segmental angles of curvature,1-3
2) Average geometric model of each spinal region based on normal subject parameters;4-6 with average total and segmental angles (means and standard deviations) of curvature for each spinal region.1-7
To claim that our model is solely an ideal geometric model (item #1 above) shows a clear lack of reading or understanding of the studies in question. Our ideal models (cervical, thoracic, and lumbar), are within 1 standard deviation of the means for the normal subject values. In CBP® technique, we offer the patient a clear choice of treatment options including the opportunity to strive for a spine that is within average values and ideal values reported in the scientific literature.1-7 Because of Dr. McDaniel’s predilection with our cervical spine model, I offer Table 1 with both average and ideal values of cervical lordosis from Index Medicus publications.
• A subtle ad hominem attack on CBP® Non-Profit’s Institutional Review Board (IRB)
Dr. McDaniel questions our informed consent protocol in a recent CBP® Non-Profit publication.8 In fact, in the manuscript in question, the full sentence appears as follows, “Subjects gave informed consent and all aspects of this project were approved by our Internal Review Board.”
Dr. McDaniel’s question is really a subtle ad hominem attack. According to Stein9, the ad hominem attack is one of the fallacies in scientific debates; instead of critiquing the science, attack the character of the individual. I believe Dr. McDaniel came to this notion from personal communication with Dr. Stephen Perle. In fact, at the 2004 Research Agenda Conference, Dr. Perle questioned the ethics of the CBP® IRB as well.10
First, “Informed Consent of Human Subjects” is a small part of an IRB procedure. For your information, “Informed Consent” is covered in Federal Register, Vol. 46, No. 17, Tuesday, January 27, 1981, Rules and Regulations, pages 8951-52. “Institutional Review Boards” is covered under Federal Register, Vol. 46, No. 17, Tuesday, January 27, 1981, Rules and Regulations, pages 8975-79.
Our CBP® IRB follows these guidelines with 5 members, 2 are women and 3 are men, one is a lawyer, one is a lay-person (PhD in Chemistry), and only 3 are chiropractors. I suggest that Dr. McDaniel and Dr. Perle stick to the facts and cease with the ad hominem attacks.
• Making a ‘big deal’ of a sentence in the study by Harrison et al.8 due to failure to read and/or cite the complete paragraph
Next, Dr. McDaniel complains of a sentence in the study by Harrison et al.8 Dr. McDaniel has taken one sentence out of the paragraph there. The following sentence states “Besides neck pain,3-5 loss of cervical lordosis and/or kyphosis, has been found to be a factor or cause of tension and migraine headaches6-8”8 Dr. McDaniel discounts the first three of these six references where abnormalities of cervical lordosis were associated with neck pain11-13 (below) because they describe post surgical patients. However, the other three link abnormalities of cervical lordosis to headaches in non-surgical subjects;14-16 (below) aren’t headaches health-related disorders, Dr. McDaniel?
I’m amazed that Dr. McDaniel does not see post-surgical outcomes as a healthcare issue related to the cervical spine. According to McGuire17, “Degeneration of segments adjacent to a prior fusion of the cervical spine can lead to neural compromise necessitating further surgery.” Over a 10-year period, the incidence of developing adjacent segmental disease is 25% and half of these cases require revision surgery. Importantly, biomechanical studies on cervical fusions in lordosis vs. kyphosis18, clinical outcome studies on post-surgical cases,11-13,19,20 and literature reviews17 all indicate that segmental and total kyphosis is linked to increased incidence of degenerative joint disease and generalized poor outcomes after cervical spine surgery. This is a serious health concern!
Lastly, subjects with chronic neck pain with/without radiculopathy and degenerative joint disease are becoming increasingly more common in their presentation to chiropractors. Conservative rehabilitation is the first line of defense against a) becoming a surgical candidate and b) prevention of surgery in cases recommended for cervical spine surgery.21
• Abnormality of cervical lordosis is not related to health disorders as three studies refute this hypothesis
Dr. McDaniel presents 3 studies supporting his opinion that abnormalities of cervical lordosis are unrelated to neck pain and degenerative joint disease (DJD).22-24 In rebuttal, I provide a review of these three studies here:
1. The study by Gore et al.22 provided average cervical lordosis measurements from a population base of 200 (100 men and 100 women between the ages of 20-65) asymptomatic subjects. No pain indices or disability questionnaires were utilized. Little differences were found for men versus women. Cervical lordosis was found to increase with age for both men and women. DJD correlated with a decreased cervical lordosis in the age range 50-65 years old (10º difference). 18/200 or 9% of subjects had a segmental kyphosis. Importantly, there were no complete reversals (kyphosis) of the cervical spine in this series of 200 subjects as in the 9% with segmental kyphosis the ARA was still 4° lordotic.
Deed’s Rebuttal: Complete cervical kyphosis is abnormal as it was not found in an asymptomatic population.22 Of interest, Hardacker et al.11 found a point prevalence for segmental kyphosis of 39% in their subjects with neck pain not requiring medication (interestingly Hardacker et al.11 designated these subjects asymptomatic?). Similarly, Harrison et al.26 found that 35% of 250 symptomatic subjects suffered from kyphotic deformities of the cervical spine. Thus, the findings from Hardacker et al.25 and Harrison et al.26 suggest that segmental kyphosis is a risk factor for neck pain (4 times greater prevalence in pain subjects compared to Gore’s22 asymptomatic subjects).
2. The 1987 study by Gore et al.23 is not the 10 year follow up of Gore et al.’s22 previous study as Dr. McDaniel has suggested. In fact, here, Gore et al.23 presented a 10-year follow up of initial neck pain subjects not asymptomatic subjects. 13/205 (6%) had complete cervical kyphosis.
Deed’s Rebuttal: Here Gore et al.23 examined an older population compared to his previous group and did not present pain/disability scales. These subjects were a conglomeration of injuries and spinal conditions including: whiplash injuries, congenital anomalies, instability of segments, chronic neck pain, radiculopathy, etc... This conglomeration of subjects makes analysis of the results questionable at best. Importantly, 6% of neck pain subjects having cervical kyphosis23 is significant compared to 0% of asymptomatic subjects.22 Further, no segmental values of cervical lordosis are presented making correlation of segmental alignment to DJD impossible. Finally, Gore27 did present a 10 year follow up to his previous report of asymptomatic subjects. A 15% incidence of neck pain was found at the 10-year follow-up. DJD in the lower cervical spine was found to statistically predict the occurrence of pain at follow up. That DJD correlates to pain and neurological dysfunction is a finding supported by previous investigators.28-31
In this 10-year follow up, Gore27 did not present information as to the global cervical lordotic alignment of the subjects with pain versus without pain, did not measure the segmental angles at the level of the degenerative changes, and did not present any information as to how many of the previous 9% with a segmental kyphosis returned or became symptomatic at the ten-year follow up.
3. Shaikewitz24 prospectively evaluated 188 subjects between the ages of 13-84 years of age using screening lateral cervical radiographs. Informed consent was provided but no IRB approval was obtained. Shaikewitz24 evaluated the cervical lordosis by the sole means of radius of curve using a drafting tool and categorized subjects into four categories: 1) normal lordosis 17cm radius after Pierce,32 2) greater than 17 cm radius until the curve was straight, 3) straightened curve, 4) kyphotic curve greater than a 17 cm radius. The primary intent was to see if correlation between DJD and cervical lordosis existed. No appreciable correlation was found.
Deed’s Rebuttal: This study’s methods are so poor I can’t believe that Dr. McDaniel didn’t realize this and that it passed the peer-review process. First, without IRB approval, it should have never made it into a peer-reviewed journal. Second, the cervical curve measurement method used had never been subjected to a reliability study. Third, the 17cm normal radius of curvature has never been validated in scientific study. Fourth, the radius of curvature is linearly dependent upon the height of the column. For example, even though the slope (exact angle of curvature) is the same for two different height cervical curves, the radius of curvature will be different (See Figure 1). Use of radius of curvature is appropriate only if the cervical curvature in these subjects is circular; which is not validated by Shaikewitz24 and is in fact, contradictory to his figures 1-3 on page 45. Also, figures 1-3 show progressive worsening of cervical lordosis with worsening of DJD, which is contradictory to the conclusion of Shaikewitz.24 Finally, teenagers (13-19 years) aren’t the age group that have DJD; why did Shaikewitz24 include this age group?
Contradicting Dr. McDaniel’s view, finite element models,18 analytical engineering stress/strain models,13,35-37 longitudinal surgical outcomes studies,13,19,20,38 non-surgical longitudinal studies,31 and cross-sectional studies39,40 all indicate that straightened, S-curves, and kyphotic cervical curves predict and/or correlate to the development and/or existence of DJD.
• Norris and Watt30 “failed to confirm that a kyphosis is associated with a poor clinical outcome”
In complete opposition to Dr. McDaniel’s assertion, Norris and Watt30 followed 61 patients involved in motor vehicle accidents for a minimum of six months. They found that abnormal cervical curves “...are more common in patients with a poor outcome.” I suggest that Dr. McDaniel actually read this study and the readers of the AJCC verify this for themselves.
Similarly, several other reports on subjects with chronic whiplash associated disorders (WAD) have linked and correlated pain, DJD, and generalized poor outcomes to abnormalities of the cervical lordosis.31,41-43 For example, in a prospective study of 110 patients, Kai et al.43 studied the relationship of neurogenic thoracic outlet syndrome (NTOS) to whiplash injury. The incidence of cervical kyphosis was 44%-46% in the patients with NTOS vs. 11-24% in subjects without NTOS. Their conclusion was that reversal of the cervical lordosis is abnormal and associated with future disability after whiplash.
• Our Spine 1996 publication1 found a “lack of pain with variations in cervical curve”
First of all, we did not present weight, height and sex of the subjects for pain versus non-pain.1 Second, since we did not analyze presence and severity of DJD in any subject, comparing pain versus non-pain subject’s curve is inappropriate in as much as DJD could have been the variable causing pain.28-31 Third, we did not analyze the pain subjects for duration (acute, subacute, and chronic) and intensity of pain. Considering these issues, retrospective comparison as Dr. McDaniel and Cooperstein44 have attempted is inappropriate.
More recently, we analyzed the cervical lordosis in three groups of subjects: normal subjects, acute, and chronic neck pain subjects.45 Similar to our previous study,1 each group was limited to only lordotic cervical spines. However, this time, we eliminated DJD in all groups and significant anterior head translation. In addition to segmental angles, we modeled the path of the posterior vertebral bodies in all subjects using an original computer iteration process. Statistical analysis including sensitivity/specificity analysis (ROC curves) was performed. Due to similar group heights, we were able to use radius of curvature as well as lordotic angles as outcomes. We found statistically significant differences and good sensitivity/specificity with angle and radius of curvature measurements (acute neck pain less than 30° and chronic neck pain less than 18°) between the groups.
In a separate evaluation of asymptomatic versus neck pain subjects, McAviney et al46 found that a 20° lordosis (posterior tangents C2-C7) was a good cutoff value (sensitivity/specificity using ROC curves). The association between cervical pain and lordosis <0° was highly significant (p<0.0001). A lordosis in the range of 31° - 40° was found to have the least percentage of symptoms and this was suggested as a clinical goal for Chiropractic treatment.
• Abnormality of cervical lordosis linked to degenerative joint disease is controversial
Review my response under the section following the study by Shaikewitz.24
• No study has determined that improvement in spinal alignment is superior to standard spinal manipulative therapy or exercise for pain syndromes
I would like to point out that Dr. McDaniel missed our other 5 clinical control trials.47-51 In two of these trials,50,51 manipulation was either not utilized at all or utilized very infrequently and significant improvement in chronic pain was still achieved. We have specifically begun addressing this critical level 4 with case studies; of which several are in press/published.52-56
Why does Dr. McDaniel only consider pain? Pain is only one of several outcomes used in managing a given health related disorder. The following is a list of outcome variables just as important as pain and which have been correlated to spinal alignment parameters:
1. Local organ ailments such as uterine prolapse,57,58 gastric herniation,59 and respiratory function,60-62
2. Cognitive function and emotion,61,63
3. Morbidity and longevity/mortality,64-68
4. Deformity progression,69
5. Muscle load and tissue stress/strain relationships,70,71
6. Increased probability of soft tissue injury during whiplash due to straightened or kyphotic cervical curves in the neutral position.72
7. Increased propensity for column buckling under impact loads due to straightened/kyphotic cervical curves in the neutral position.73
• Adequate pain control can be achieved (with less visits and expense) by SMT alone as compared to CBP®’s Structural Rehabilitation procedures
This is an opinion statement and not supported by any evidence. This would require extensive analysis of different pain syndromes treated with SMT compared to those treated with CBP® structural rehabilitative procedures. Since this has never been performed, Dr. McDaniel’s statement is neither supported nor refuted and statements like these should not be made.
Of interest, though, is the statement adequate pain control can be achieved with SMT alone. In a recent randomized clinical trial (RCT), Hurwitz et al.74 demonstrated that chronic neck pain was only reduced from a 7-8/10 down to a 5/10 following SMT and/or mobilization techniques. I ask Dr. McDaniel, “Is this adequate pain control, should we leave patients at a 5/10 and tell them to suffer with chronic pain because that’s all they get with SMT and an RCT has not been performed proofing relief via structural rehab?” Or do we make clinical decisions based on:
1) The ‘best available evidence, realizing that RCT’s don’t apply to actual clinical practice,75,76
2) That non-randomized clinical control trials (such as CBP®’s 68,47-51) are high quality studies on chronic pain subjects,
3) That the outcomes of well designed case studies (such as CBP®’s 52-56) show similar outcomes to RCT’s done on the same condition.77,78
Recently, the buzzwords ‘evidence-based practice’ (EBP) have appeared in clinical practice protocols. EBP is defined as clinical decision-making based on, (1) sound external research evidence combined with individual clinical expertise and, (2) the needs of the individual patient.75,79 The problem is EBP depends on ‘what you call evidence, the evidence you choose to use, and the evidence you choose to ignore,’ Dr. McDaniel.
• My report of findings for a patient with neck pain and a straightened cervical curve
Before I address this, three things come to mind, 1) does Dr. McDaniel work for the report of findings police?; 2) this case history is significantly lacking a number of relevant issues; and 3) what does this have to do with CBP® Technique? Isn’t this topic practice management?
Ignoring the above, I would inform her that a straightened cervical lordosis has been correlated to neck pain,45,46 propensity for early or progression of DJD,13,18,19,20,31,35-40 and increased probability of more severe injury should she be involved in a whiplash injury72 or sustain head trauma.73 I would offer her three treatment options:
1) No treatment,
2) Relief for her neck pain solely using SMT, myofascial, pnf stretching, ice/heat as needed. This would consist of 12 visits over 3 weeks with an ending re-examination.
3) Relief care combined with CBP® structural rehab care designed to improve the cervical lordosis to within evidence based values (30°-40°).1,45,46 This would include a re-exam after 12 visits and 36 visits (24 visits of CBP® care over 6 weeks added to the previous 12 visits). This recommendation is based on the clinical implementation of the best available evidence on spinal treatment using CBP® Technique.8,47-56
Conclusion
Dr. McDaniel’s arguments fall short due to the fact that he based his critiques on an incomplete/selective literature review, an inappropriate representation of studies in the literature due to secondary citations and/or a failure to understand what he read, and his reliance on pain as the only outcome of patient care.
Round 1: Need judges’ opinion. Dr. McDaniel, care for round 2?
References
1. Harrison DD, Janik TJ, Troyanovich SJ, Holland B. Comparisons of lordotic cervical spine curvatures to a theoretical ideal model of the static sagittal cervical spine. Spine 1996; 21: 667-675.
2. Janik TJ, Harrison DD, Cailliet R, Troyanovich SJ, Harrison DE. Can the Sagittal Lumbar Curvature be Closely Approximated by an Ellipse? J Orthop Res 1998; 16(6): 766-770.
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4. Harrison DD, Cailliet R, Janik TJ, Troyanovich SJ, Harrison DE. Elliptical Modeling of the Sagittal Lumbar Lordosis and Segmental Rotation Angles as a Method to Discriminate Between Normal and Low Back Pain Subjects. J Spinal Disord 1998; 11(5):430-439.
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6. Harrison DD, Harrison DE, Janik TJ, Cailliet R, Haas JW, Ferrantelli J, Holland B. Modeling of the Sagittal Cervical Spine as a Method to Discriminate Hypo-Lordosis: Results of Elliptical and Circular Modeling in 72 Asymptomatic Subjects, 52 Acute Neck Pain Subjects, and 70 Chronic Neck Pain Subjects. Spine 2004; 29:2485-2492.
7. Troyanovich SJ, Cailliet R, Janik TJ, Harrison DD, Harrison DE. Radiographic Mensuration Characteristics of the Sagittal Lumbar Spine From A Normal Population with a Method to Synthesize Prior Studies of Lordosis. J Spinal Disord 1997;10(5): 380-386.
8. Harrison DE, Harrison DD, Betz J, Janik T, Holland B, Colloca C, Haas J. Increasing the Cervical Lordosis with Chiropractic Biophysics Seated Combined Extension-Compression and Transverse Load Cervical Traction with Cervical Manipulation: Nonrandomized Clinical Control Trial. JMPT 2003; 26(3):139-151.
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