
==== Front
J Clin Imaging Sci
J Clin Imaging Sci
JCIS
Journal of Clinical Imaging Science
2156-7514
2156-5597
Scientific Scholar

10.25259/JCIS_68_2024
10.25259/JCIS_68_2024
Review Article
Musculoskeletal Imaging
An investigation into the chiropractic practice and communication of routine, repetitive radiographic imaging for the location of postural misalignments
Williams Brogan 1
Gichard Luke 1
Johnson David 2
Louis Matthew 3
1 Department of Research, College of Functional Movement Clinicians, Auckland, New Zealand,
2 Department of Research and Neurosurgery, The Back Pain and Functional Movement Training Centre, Brisbane, Australia,
3 Department of Research, Apollo Spine Rehabilitation, New Jersey, United States.

* Corresponding author: Brogan Williams, Department of Research, College of Functional Movement Clinicians, Auckland, New Zealand. brogan.s.williams@gmail.com
01 8 2024
2024
14 2817 6 2024
18 6 2024
© 2024 Published by Scientific Scholar on behalf of Journal of Clinical Imaging Science
2024
Journal of Clinical Imaging Science
https://creativecommons.org/licenses/by-nc-sa/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-Share Alike 4.0 License, which allows others to remix, transform, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms.
Many chiropractors use radiological imaging, particularly X-rays, to locate and diagnose the cause of their patients’ pain. However, this approach is fundamentally flawed because X-rays provide anatomical information but not functional insights. Pain, tissue damage, and injury do not always correlate directly with X-ray appearances. Given the high incidence of abnormalities found in X-rays of asymptomatic patients, the diagnostic validity of X-rays can be questioned, especially when used in isolation of the patient’s history and/or a proper clinical assessment. One may posit that their application promotes overdiagnosis, and unvalidated treatment of X-ray findings (such as changes in postural curvature), which may mislead patients into believing these changes are directly responsible for their pain. A substantial amount of research has shown that there is no association between pain and reversed cervical curves. X-ray accuracy can vary due to several factors, including patient positioning, physical and morphological changes, interreliability among doctors, and other influences such as stress, pain, and emotional state. Over the past two decades, medical boards and health associations worldwide have made significant efforts to communicate better when imaging is necessary, focusing on reducing radiographic imaging. This review describes concerns about the frequent, almost routine use of spinal X-rays in primary care for spine-related pain in the absence of red-flag clinical signs.

Radiographic imaging
X-ray
Chiropractic
Subluxation
Financial support and sponsorship Nil.
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pmcINTRODUCTION

The use of radiology is integral to modern medicine and health care. However, certain fractions of the chiropractic health-care profession have been known to use them routinely and repetitively to locate postural syndromes and “subluxation” misalignments.[1] The use of X-rays for postural purposes or subluxation misalignments is concerning, considering the large amount of current research and literature on this issue. In addition, there is apprehension about the strong language chiropractic physicians choose to use and the methods that may be employed when presenting postural lines.

Many chiropractors utilize postural lines with the intention of providing an analysis of overall spinal alignment and posture.[2-4] In the traditional Gonstead technique, postural line analysis is deemed extremely important in locating “vertebral subluxations” within the spine.[2,3] A common aspect of postural line analysis includes placing extended lines across the inferior vertebral endplates of the lateral cervical, thoracic, and lumbosacral radiographic images.[3-5] These specific lines are obtained to compare the segment above with the one below to determine the “posteriority” of a segment, which is conclusive when the extended lines converge posteriorly at a greater, or more significant angle.[3] Furthermore, they are commonly drawn to communicate the patient’s overall spinal curvature and increased weight-bearing that may be occurring at specific structures, for example, anterior head carriage and reversal of the cervical lordotic curve.[3,5,6]

Postural analysis of the lumbopelvic region is also commonly used to validate treatment approaches and communicate a patient’s spinal health.[3,7] The ilium analysis is constructed based on points placed at various anatomical positions on the ilium and sacrum, which give particular measurements to draw conclusions.[3] It is not unheard of for patients to report that their previous chiropractor informed them their pelvis is “misaligned” or “rotated.” Various factors can influence this approach to a patient’s assessment, including alteration of patient positioning, variation in an individual’s anatomy, inter-examiner reliability, and overall image quality.[8-12]

These postural lines are believed to be important in validating specific vertebral segments to manipulate; however, they also provide a potentially unethical framework to communicate an individual’s spinal health through static imaging.[13-15] This can lead to an exaggeration of the severity of an individual’s health, leaving the individual pressured into beginning or continuing care. The diagnostic validity, accuracy, ethics, and safety are questioned in this review.

DIAGNOSTIC VALIDITY

Many clinicians use radiographic imaging to locate and diagnose the cause of their patient’s pain. Research shows pain, tissue damage, and injury are not always directly correlated. It remains non-conjectural that many pain-free individuals have identical structural changes on X-rays that are also observed in patients with pain. A cause-and-effect relationship clearly does not exist. Due to the high incidence of abnormalities found in asymptomatic patients, the diagnostic validity of X-rays can be questioned when used in isolation of history and proper clinical assessment. Kiuru et al. reported that out of 75 detected bone injuries on scans, only 30 were symptomatic.[16] Horga et al. found that when scanning 115 uninjured, asymptomatic adults, 97% presented with some type of abnormal knee finding, such as a tear, rupture, tendonitis, or cartilage lesions. Furthermore, things become increasingly concerning when we look at back pain.[17] In fact, a 2015 systematic literature review consisting of 3110 asymptomatic individuals reported shocking results.[18] About 37–96% had disk degeneration, 30–84% had a disk bulge, 4–83% had facet degeneration, and 3–50% had a spondylolisthesis – all asymptomatic, pain-free individuals. Many guidelines from the United States and Europe discourage routine X-ray scans for low back pain (LBP) without red flags.[19] Furthermore, various studies have found that serious pathology is present in 0.2–3.1% of people with LBP, with fractures accounting for 0.2–6.6%.[20-23] Finally, research shows that using X-rays prematurely in cases where there are no red flags can have negative health outcomes, such as increased radiation, more doctor follow-ups, poorer self-test health status, more pain, and overall dissatisfaction.[19] There is no evidence to suggest that X-rays should be used to diagnose benign radiographic findings that do not improve patient outcomes.[1] In addition, there is no evidence to support the idea that specific asymptomatic radiographic findings, such as spondylolisthesis, transitional segments, or degeneration, should alter how these conditions are treated in a clinical setting if they have already been identified through a thorough history or physical examination.[1]

A study by Beck et al. investigated radiographic anomalies that may affect patient outcomes through chiropractic intervention.[21] The five most common anomalies that were reported radiographically were degenerative changes (23.8%), posterior ponticle (13.6%), soft-tissue anomalies (13.5%), transitional segments (9.8%), and spondylolisthesis (7.8%).[21] Many of these anomalies may or may not alter patient outcomes over a period of chiropractic intervention, so it is important that a thorough history and physical examination are taken to gain full information. Of the radiographs that were obtained from the individuals, only 11.6% were symptomatic, and 69.4% showed some sort of anomaly.[21] Is this enough evidence to routinely image a patient for the purpose of biomechanical alterations and certain anomalies? Is it worth the unnecessary costs and radiation exposure when other interventions could be used instead of manipulation?

POSTURE AND PAIN

Clinicians may use radiographic imaging to validate therapeutic interventions for their patients. One technique is presenting postural changes on an X-ray (such as reversed curves) and convincing the patient that this is directly responsible for their pain. This presents an ethical dilemma, and the practice is not backed by research.[24] A substantial amount of research shows that there is no association between pain and reversed cervical curves.[25] A Beltsios et al. study compared radiographic imaging of injured and non-injured participants. However, when they tried to draw a correlation between spinal injury and poor postural curvatures, they could not – there was no significant difference between both groups.[26] In addition, a Christensen and Hartvigsen systematic critical review found there to be no association between postural curvatures and overall health.[27] Murrie et al. reported no link between a reversed lumbar lordosis and pain either.[28] In 2014, Kumagai et al. studied 762 volunteers. When trying to link sagittal cervical alignment and neck symptoms, once again, they could not – concluding there was no association present.[29] Moreover, Matsumoto et al. prospectively studied almost 1000 cervical X-rays (495: Asymptomatic; 488: Acute whiplash). His overwhelmingly conclusive results showed no significant differences in cervical lordosis between the two groups, concluding that reversed postural curves are likely a normal variant and NOT pathological.[30]

The overwhelming amount of non-biased literature supports that cervical lordosis or reversed postural curves are not associated with pathology or pain.[24-33]

ACCURACY

Accuracy can also be questioned, as X-ray measurements can vary based on an overwhelming number of factors, such as patient positioning, patient physical and morphological changes over time, doctor inter-reliability, stress, pain, the patient’s previous night’s sleep or physical activity, hydration, and/or emotional state.[8-12] In fact, Beauchamp et al. found a 5° difference in Cobb’s angle in participants with scoliosis who were radiographed at 8 am compared–8 pm.[34] If orthopedic surgeons misinterpret such gross angles, how confident can we be when certain professions claim to accurately locate extremely small spinal misalignments, or “vertebral subluxations”? Furthermore, Triano et al. concluded that the use of spinal X-rays had been found to be a poor method of detecting specific areas of spinal manipulation.[35]

SUBLUXATION

A vertebral subluxation is a term and condition created by chiropractors that refer to misalignment of the vertebra, a bone out of place, causing pressure on the spinal nerve, and interference with mental impulses[36]. Subluxation is a legitimate medical condition; however, this completely differs from the condition used by chiropractors. Over the years, there have been numerous definitions and takes on what “vertebral subluxation” is – even though the term and concept date back to 1902, it is still commonly used in the chiropractic community.[36] It has been described that the misalignment of the vertebra causes occlusion of where the spinal nerve travels, thus causing nerve pressure and disrupting the “mental impulse,” which is part “intelligence,” a synonym for “spirit,” and part of the “mental realm,” and part neural impulse, which is part of the physical realm. Many chiropractors believe that when bones press on nerves, the corresponding organ on the other end of the nerve will suffer disease.[37] Many clinicians use this “condition” as grounds to order unnecessary radiographic imaging. Extensive medical research has shown that bones do not slip out of place, squishing nerves and causing various and different pathologies – and there is certainly no way to scientifically prove the interference of a “spirit” or life force. Nonetheless, none of this is grounds for ordering an X-ray and does not qualify as any type of “red flag,” raising concern about how and when chiropractors are using radiographic imaging.

The Rubicon Group is a collaboration of chiropractic educational institutions that combine traditional chiropractic principles, vitalistic philosophy, and a neurophysiological approach.[38] Their approach is to move away from the traditional pressure on nerve theory and become more research and evidence-based. They currently define a “vertebral subluxation” as “a self-perpetuating, central segmental motor control problem that involves a joint, such as a vertebral motion segment, that is not moving appropriately, resulting in ongoing maladaptive neural plastic changes that interfere with the central nervous system’s ability to self-regulate, self-organize, adapt, repair, and heal”.[38]

SAFETY CONSIDERATIONS

The overuse of radiographs is increasing. The possible risks must be considered and assessed within the context of the utility. Corso et al. reported that, apart from red flags, there was no evidence showing routine radiographs were necessary for the assessment of spinal structures, nor did they provide any clinical value or patient benefit given the inherent risk of radiation.[39] Furthermore, research has concluded that there is strong evidence linking various potential harms with routine, repeated X-rays, such as altered treatment procedures, overdiagnosis, radiation exposure, and unnecessary costs.[1] A real concern also exists relating to undiagnosed soft-tissue pathology in the presence of pain and clinical red flags when X-rays are relied on. The potential for missed diagnosis is attributed to the poor sensitivity and false-negative rate of X-ray investigations compared with the exquisite resolution capability of magnetic resonance imaging (MRI) and computed tomography (CT) scanning. Both clinician and patient may develop a false sense of security from the “normal” appearing X-ray. This may contribute to the delayed diagnosis of soft-tissue pathology when more advanced imaging is prudently ordered in the case of persistent symptoms. If clinical concerns arise, hesitation to obtain high-resolution imaging with CT (or MRI) scans should not be a factor based on radiation dose or cost.

UNETHICAL COMMUNICATION

Spinal X-rays can lead to the detection of radiographic findings that can be used as an overdiagnosis for the patient, even though they may be asymptomatic. These include spinal anomalies, osteophytes, reduced disk heights, low-grade spondylolisthesis, transitional segments, and spina bifida occulta. The chiropractor can use all radiographic findings as “scare tactics” or “fear-mongering” to retain a patient under a specific frequency of care, thus creating unnecessary concern for the patient. Multiple studies have concluded that radiographic findings do not always correlate with a patient’s symptomatology.[18,40,41] Brinjikji et al. concluded that disk degeneration was present in asymptomatic individuals, ranging from 37% in 20 year olds to 96% in 80 year olds.[18]

Many chiropractors use “phases of degeneration” as a method of communication in order for patients to adhere to excessive treatment plans.[13] It is unnecessary and unethical to scare patients to obtain compliance with chiropractic care.[13] These “scare tactics” can negatively influence patients’ behavior, especially those who already experience reduced levels of self-efficacy.[14,15] This unnecessary use of communication can potentially cause negative thoughts, leading to fear and avoidance of physical activity and management advice as there is a concern for further damage.[42] In addition, the likelihood that a patient will experience chronic pain may arise due to the belief that they won’t get better until the radiographic findings are resolved.[43]

CURRENT GUIDELINES

Over the past two decades, medical boards and health associations worldwide have made a substantial effort to communicate better “when” imaging is required, with most education around the reduction of X-rays/CTs/MRIs in medical cases that do not present any red flags.[44] In fact, the American Board of Internal Medicine’s worldwide initiative “Choosing Wisely” (which advocates for better dialogue around unnecessary medical tests and procedures) has openly stated that they recommend against initial imaging unless red flags are present.[45] This notion is supported widely in the literature, with many medical journals suggesting conservative care and no imaging is preferred for up to 6 weeks with conditions referred to as “Non-Specific Low Back Pain” (NSLBP).[46] In addition, Australian guidelines have advised against diagnostic imaging for routine assessment of patients with NSLBP, with research showing, there is no evidence to indicate imaging in the absence of red flags produces any improved clinical or patient outcomes while practicing outside these guidelines does yield possible negatives, such as unnecessary health system and patient costs and radiation exposure to the patient.[44] Major concerns around the possible inappropriate or unethical use of imaging (specifically around NSLBP) have caused the issuance of various practical and clinical guidelines around the usage of X-rays/CTs/MRIs worldwide. The American Academy of Family Physicians recommends withholding imaging for LBP within the first 6 weeks of symptom onset unless clinical “red flags” are present. The American Association of Neurological Surgeons and Congress of Neurological Surgeons recommend withholding all imaging of the spine in patients with nonspecific acute LBP and without “red flags.”[47]

Furthermore, the “Canadian C-spine Rule” and others like it utilize strict objective criteria to determine whether radiographic imaging is required for patients following trauma.[48] Criteria such as age >65, high-risk mechanisms of injury, midline tenderness, altered conscious state, neurological deficits, other distracting injuries, or known pre-existing spinal disease all mandate imaging and afford a satisfactorily high sensitivity and negative predictive value for significant cervical spine injury.[48,49]

RED FLAGS

X-rays and imaging are integral to the development of modern medicine, with millions of lives saved worldwide, including the location and prevention of life-threatening illnesses, diseases, and cancers. It is necessary to use imaging; however, appropriate education is paramount for the therapist or clinician to understand the valid utility of imaging, including plain X-rays. As described in this review, the use of repeated imaging for postural or spinal misalignments is not advised by worldwide governing health authorities and is not supported in most current guidelines. Red flags when screening for LBP are as follows: history of cancer with new onset of LBP, unexplained weight loss, failure to improve after 1 month, age >50 years, night pain, fever, intravenous drug use, recent severe bacterial infection, immunocompromised state, fecal incontinence, saddle anesthesia, lower limb weakness or numbness, history of osteoporosis, prolonged use of corticosteroids, older age, history of fall, or other trauma.[50] In these circumstances, consideration should be given to high-resolution MRI imaging, given that a normal X-ray and even a CT scan still necessitate the superior soft-tissue resolution provided by MRI.

CONCLUSION

The importance of medical imaging cannot be overstated. Medical professionals, on the other hand, must adhere to ethical and responsible standards. These guidelines may be ambiguous in some situations, professions, and countries, resulting in many grey areas of practice. As discussed in this article, the ongoing justification many use to justify the excessive, repetitive, and ongoing use of X-rays for reasons that research does not support is highly concerning. This article highlights potential unvalidated practices within the chiropractic field relating to poor utility imaging.

Ethical approval

The Institutional Review Board approval is not required.

Declaration of patient consent

Patient’s consent is required as there are no patients in this study.

Conflicts of interest

There are no conflicts of interest.

Use of artificial intelligence (AI)-assisted technology for manuscript preparation:

The authors confirm that there was no use of artificial intelligence (AI)-assisted technology for assisting in the writing or editing of the manuscript and no images were manipulated using AI.

How to cite this article: Williams B, Gichard L, Johnson D, Louis M. An investigation into the chiropractic practice and communication of routine, repetitive radiographic imaging for the location of postural misalignments. J Clin Imaging Sci. 2024;14:28. doi: 10.25259/JCIS_68_2024
==== Refs
1. Jenkins HJ Downie AS Moore CS French SD Current evidence for spinal X-ray use in the chiropractic profession: A narrative review Chiropr Man Therap 2018 26 48 10.1186/s12998-018-0217-8 30479744
2. Zengel F Davis BP Biomechanical analysis by chiropractic radiography: Part III. Lack of effect of projectional distortion on Gonstead vertebral endplate lines J Manipulative Physiol Ther 1988 11 469 73 3075648
3. Cooperstein R Gonstead chiropractic technique (GCT) J Chiro Med 2003 2 16 24 10.1016/S0899-3467(07)60069-X 19674591
4. Coleman RR Harrison DE Fischer T Harrison SO Correlation and quantification of relative 2-dimensional projected vertebral endplate z-axis rotations with 3-dimensional y-axis vertebral rotations and focal spot elevations J Manipulative Physiol Ther 2000 23 414 9 10.1067/mmt.2000.108141 10951312
5. Harrison DE Harrison DD Cailliet R Troyanovich SJ Janik TJ Holland B Cobb method or Harrison posterior tangent method Spine (Phila Pa 1976) 2000 25 2072 8 10.1097/00007632-200008150-00011 10954638
6. Oakley PA Ehsani NN Harrison DE Repeat radiography in monitoring structural changes in the treatment of spinal disorders in chiropractic and manual medicine practice: Evidence and safety Dose Response 2019 17 10.1177/1559325819891043 31839759
7. Harrison DE Harrison DD Colloca CJ Betz J Janik TJ Holland B Repeatability over time of posture, radiograph positioning, and radiograph line drawing: An analysis of six control groups J Manipulative Physiol Ther 2003 26 87 98 10.1067/mmt.2003.15 12584507
8. Adkin AL Carpenter MG New insights on emotional contributions to human postural control Front Neurol 2018 9 789 10.3389/fneur.2018.00789 30298048
9. Barros LM Hoshino K Sleepiness and inadequate bodily posture in the classroom: Does laziness intermediate a relationship? Sleep Sci 2011 4 88 92
10. Tudor GR Finlay D Taub N An assessment of inter-observer agreement and accuracy when reporting plain radiographs Clin Radiol 1997 52 235 8 10.1016/S0009-9260(97)80280-2 9091261
11. Derave W Clercq DD Bouckaert J Pannier JL The influence of exercise and dehydration on postural stability Ergonomics 1998 41 782 9 10.1080/001401398186630 9629063
12. Dewi DE Veldhuizen AG Burgerhof JG Purnama IK van Ooijen PM Wilkinson MH et al Reproducibility of standing posture for X-ray radiography: A feasibility study of the BalanCaid with healthy young subjects Ann Biomed Eng 2010 38 3237 45 10.1007/s10439-010-0062-y 20473569
13. Gliedt JA Schneider MJ Evans MW King J Eubanks JE The biopsychosocial model and chiropractic: A commentary with recommendations for the chiropractic profession Chiropr Man Therap 2017 25 16 10.1186/s12998-017-0147-x 28593041
14. Peters GJ Ruiter RA Kok G Threatening communication: A critical re-analysis and a revised meta-analytic test of fear appeal theory Health Psychol Rev 2013 7 S8 31 10.1080/17437199.2012.703527 23772231
15. Kok G Bartholomew LK Parcel GS Gottlieb NH Fernández ME Finding theory-and evidence-based alternatives to fear appeals: Intervention mapping Int J Psychol 2013 49 98 107 10.1002/ijop.12001 24811880
16. Kiuru MJ Niva M Reponen A Pihlajamäki HK Bone stress injuries in asymptomatic elite recruits Am J Sports Med 2005 33 272 6 10.1177/0363546504267153 15701614
17. Horga LM Hirschmann AC Henckel J Fotiadou A Di Laura A Torlasco C et al Prevalence of abnormal findings in 230 knees of asymptomatic adults using 3.0 T MRI Skeletal Radiol 2020 7 1099 107 10.1007/s00256-020-03394-z 32060622
18. Brinjikji W Luetmer PH Comstock B Bresnahan BW Chen LE Deyo RA et al Systematic literature review of imaging features of spinal degeneration in asymptomatic populations Am J Neuro 2015 36 811 6 10.3174/ajnr.A4173 25430861
19. Allan GM Spooner GR Ivers N X-ray scans for nonspecific low back pain Can Fam Physician 2012 58 275 22518897
20. Henschke N Maher CG Refshauge KM Herbert RD Cumming RG Bleasel J et al Prevalence of and screening for serious spinal pathology in patients presenting to primary care settings with acute low back pain Arthritis Rheum 2009 60 3072 80 10.1002/art.24853 19790051
21. Beck RW Holt KR Fox MA Hurtgen-Grace KL Radiographic anomalies that may alter chiropractic intervention strategies found in a New Zealand population J Manipulative Physiol Ther 2004 27 554 9 10.1016/j.jmpt.2004.10.008 15614242
22. Wnuk NM Alkasab TK Rosenthal DI Magnetic resonance imaging of the lumbar spine: Determining clinical impact and potential harm from overuse Spine J 2018 18 1653 8 10.1016/j.spinee.2018.04.005 29679728
23. Ferrari R Imaging studies in patients with spinal pain: Practice audit evaluation of choosing wisely canada recommendations Cam Fam Physician 2016 62 e129 37
24. Gay RE The curve of the cervical spine: Variations and significance J Manipulative Physiol Ther 1993 16 591 4 8133194
25. Grob D Frauenfelder H Mannion AF The association between cervical spine curvature and neck pain Eur Spine J 2006 16 669 78 10.1007/s00586-006-0254-1 17115202
26. Beltsios M Savvidou O Mitsiokapa EA Mavrogenis AF Kaspiris A Efstathopoulos N et al Sagittal alignment of the cervical spine after neck injury Eur J Orthop Surg Traumatol 2012 23 47 51 10.1007/s00590-012-0966-3 23412281
27. Christensen ST Hartvigsen J Spinal curves and health: A systematic critical review of the epidemiological literature dealing with associations between sagittal spinal curves and health J Manipulative Physiol Ther 2008 31 690 714 10.1016/j.jmpt.2008.10.004 19028253
28. Murrie VL Dixon AK Hollingworth W Wilson H Doyle TA Lumbar lordosis: Study of patients with and without low back pain Clin Anat 2003 16 144 7 10.1002/ca.10114 12589669
29. Kumagai G Ono A Numasawa T Wada K Inoue R Iwasaki H et al Association between roentgenographic findings of the cervical spine and neck symptoms in a Japanese community population J Orthop Sci 2014 19 390 7 10.1007/s00776-014-0549-8 24570299
30. Matsumoto M Fujimura Y Suzuki N Toyama Y Shiga H Cervical curvature in acute whiplash injuries: Prospective comparative study with asymptomatic subjects Injury 1998 29 775 8 10.1016/S0020-1383(98)00184-3 10341902
31. Cooperstein R Perle SM Gleberzon BJ Peterson DH Flawed trials, flawed analysis: Why CBP should avoid rating itself J Can Chiropr Assoc 2006 50 97 102 17549172
32. Bussières AE Ammendolia C Peterson C Taylor JA Ionizing radiation exposure-more good than harm? The preponderance of evidence does not support abandoning current standards and regulations J Can Chiropr Assoc 2006 50 103 6 17549173
33. Cacciola F Lippa L Lippa L Loss of cervical lordosis: What is the prognosis? J Cranioverter Junction Spine 2017 8 9 14 10.4103/0974-8237.199877 28250631
34. Beauchamp M Labelle H Grimard G Stanciu C Poitras B Dansereau J Diurnal variation of Cobb angle measurement in adolescent idiopathic scoliosis Spine (Phila Pa 1976) 1993 18 1581 3 10.1097/00007632-199309000-00002 8235834
35. Triano JJ Budgell B Bagnulo A Roffey B Bergmann T Cooperstein R et al Review of methods used by chiropractors to determine the site for applying manipulation Chiropr Man Therap 2013 21 36 10.1186/2045-709X-21-36 24499598
36. Senzon SA The chiropractic vertebral subluxation part 2: The earliest subluxation theories from 1902 to 1907 J Chiropr Humanit 2018 25 22 35 10.1016/j.echu.2018.10.009 31019418
37. Senzon SA The chiropractic vertebral subluxation part 4: New perspectives and theorists from 1916 to 1927 J Chiropr Humanit 2018 25 52 66 10.1016/j.echu.2018.05.001 31019420
38. The Rubicon Group Policies - The Rubicon Group 2017 Available from: https://www.therubicongroup.org/policies
39. Corso M Cancelliere C Mior S Kumar V Smith A Côté P The clinical utility of routine spinal radiographs by chiropractors: A rapid review of the literature Chiropr Man Therap 2020 28 33 10.1186/s12998-020-00323-8 32641135
40. Rudy I Poulos A Owen L Batters A Kieliszek K Willox J et al The correlation of radiographic findings and patient symptomatology in cervical degenerative joint disease: A cross-sectional study Chiropr Man Therap 2015 23 9 10.1186/s12998-015-0052-0 25671078
41. Van Tulder MW Assendelft WJ Koes BW Bouter LM Spinal radiographic (Phila Pa 1976) findings and nonspecific low back pain Spine (Phila Pa 1976) 1997 22 427 34 10.1097/00007632-199702150-00015 9055372
42. Edwards RR Dworkin RH Sullivan MD Turk DC Wasan AD The role of psychosocial processes in the development and maintenance of chronic pain J Pain 2016 17 T70 92 10.1016/j.jpain.2016.01.001 27586832
43. Flynn TW Smith B Chou R Appropriate use of diagnostic imaging in low back pain: A reminder that unnecessary imaging may do as much harm as good J Orthop Sports Phys Ther 2011 41 838 46 10.2519/jospt.2011.3618 21642763
44. Morgan T Wu J Ovchinikova L Lindner R Blogg S Moorin R A national intervention to reduce imaging for low back pain by general practitioners: A retrospective economic program evaluation using Medicare Benefits Schedule data BMC Health Serv Res 2019 19 983 10.1186/s12913-019-4773-y 31864352
45. Hall AM Aubrey-Bassler K Thorne B Maher CG Do not routinely offer imaging for uncomplicated low back pain BMJ 2021 37 291 10.1136/bmj.n291 33579691
46. Lateef H Patel D What is the role of imaging in acute low back pain? Curr Rev Musculoskelet Med 2009 2 69 73 10.1007/s12178-008-9037-0 19468875
47. Rao D Scuderi G Scuderi C Grewal R Sandhu SJ The use of imaging in management of patients with low back pain J Clin Imaging Sci 2018 8 30 10.4103/jcis.JCIS_16_18 30197821
48. Stiell IG Wells GA Vandemheen KL Clement CM Lesiuk H Maio VJ et al The Canadian C-spine rule for radiography in alert and stable trauma patients JAMA 2001 286 1841 8 10.1001/jama.286.15.1841 11597285
49. Michaleff ZA Maher CG Verhagen AP Rebbeck T Lin CW Accuracy of the Canadian C-spine rule and NEXUS to screen for clinically important cervical spine injury in patients following blunt trauma: A systematic review CMAJ 2012 184 E867 76 10.1503/cmaj.120675 23048086
50. Ramanayake RP Basnayake BM Evaluation of red flags minimizes missing serious diseases in primary care J Family Med Prim Care 2018 7 315 8 10.4103/jfmpc.jfmpc_510_15 30090770
