From a clinical standpoint, MUA has never been questioned as an alternative to correcting fixated articulation, and shortened muscles. But, as a procedure performed by the chiropractic profession, it...
Each article in the MILLION DOLLAR CHIROPRACTIC series (M$C) focuses on the top surveyed issues facing chiropractors today. Recruiting new patients, retention, profitability, marketing and staffing...
Abstract:
Vitamin D insufficiency has been associated with increased risk of CVD, various cancers, autoimmune disease and type 2 diabetes. Despite adequate sun exposure, individuals inhabiting...
In my experience, there is a general lack of appreciation of both the need for radiographic views of the thoracic spine and the influence of the thoracic spine on whole body alignment and health potential. It is for these reasons that I offer this particular series of articles introducing my thoughts on the thoracic kyphosis to readership of the The American Chiropractor.
Radiographic Measurements
In the early 1980’s, my father--Dr. Donald Harrison1--developed specific radiographic measurement methods to assess the magnitude and distribution of the thoracic kyphosis. These measurements were termed “the Harrison Posterior Tangents.” Later (2001), we investigated the reliability of these kyphosis measures and identified small standard errors of measurement and good to excellent intra- and inter-examiner reliability.2 Figure 1 shows the Harrison posterior tangent method.
Average Thoracic Kyphosis Angles
Several studies have reported “normal” values of thoracic kyphosis in a wide range of age groups.3-5 The density of the upper ribcage, in the coronal plane, can cause an inability to accurately identify and measure the vertebral segments T1-T4. Because of this, various authors have utilized different vertebral levels when measuring the thoracic kyphosis and a large range of values for kyphosis (20° to 50°) has been reported.3,4
Problematically, some of this normal subject data is contaminated with subjects that should not be considered healthy. For one example, Fon, et al.,5 presented thoracic kyphosis measurement in 316 “normal subjects” aged 2-77 yrs. Their definition of normal was: “…while the general status of some of these patients was not optimal, it was assumed that the patients were sufficiently fit to be ambulatory….”
Beginning in 2001, my colleagues and I proposed a more narrow distribution of thoracic kyphosis values as normal: average values for T3-T10 posterior tangents = 33°-37°.3,4 Part of our reasoning for a narrower range of normal thoracic kyphosis was based on a study done in 2002.6 Here, we identified that translated postures of the ribcage relative to the pelvis in the sagittal plane can have a strong influence on the magnitude of thoracic kyphosis. Specifically, a total change of 26° in thoracic kyphosis was found for maximum posterior translation of the ribcage to maximum anterior translation in normal subjects. (See Figure 2.)
Poorer health status, increased disability, and increased pain levels in patients with anterior trunk postures.
Furthermore, biomechanical models have predicted large increases in extensor muscle loads and consequent increased compression and shear loads on the thoraco-lumbar spine discs when sagittal trunk translation is present.7,8 These high compressive and shear loads may produce pain and initiate or contribute to a degenerative remodeling response in the disc. In fact, Glassman, et al.9, identified poorer health status, increased disability, and increased pain levels in patients with anterior trunk postures.
The issues associated with sagittal plane ribcage translation prompted my colleagues and I4 to present thoracic kyphosis data from a group of 50 normal subjects whose sagittal translation was within 1 standard deviation of the mean (neutral alignment). This data is presented in Table 1.
Average & Ideal Thoracic Kyphosis Models
Harrison and colleagues3 presented average geometric models of the thoracic kyphosis (T1-T12, T2-T11, and T3-T10 segments were modelled) as a segment of an ellipse using pooled data from 80 normal subjects’ lateral thoracic radiographs. Figure 3 shows the average elliptical model of the segments T1-T12.3
Harrison, et al.4 followed this paper with an optimized elliptical model of thoracic kyphosis based in part on data from 50 optimized normal subjects. Since the thoracic vertebral bodies increase in size considerably from T1 to T12, a uniformly increasing model was derived for disc and vertebral body sizes using anatomical literature. We found that the major axis of the ellipse (long axis of an oval) is parallel to the posterior body margin of T12, whereas the minor axis of the ellipse (short axis of the oval) passed through the superior endplate of T12. The minor axis to major axis ratio was computed to be 0.69.4Figure 4 shows this optimized elliptical model in a template form that can be used for any height of a patient.
In the more recent literature, investigators have begun to develop individual subject optimized geometric sagittal plane curve models for thoracic kyphosis.10-12 There are certain anatomic variables that have been shown to have a moderate influence on sagittal plane curvature. When these anatomic variables are outside of normal tolerances, a change in sagittal curvature can result. This information will be detailed in Part 2 of this series.
Summary
Chiropractic has a long history of identifying and attempting to restore normal alignment to the spine, where abnormal alignment is specifically referred to as the mechanical component of vertebral subluxation. The key is to fully understand when the modelling and alignment data presented herein is useful in differentiating a subluxated thoracic spine from a normal spine and how to modify the data and intervene in specific patient situations. Till next time.
Dr. Deed will be presenting a comprehensive, contemporary review of this topic at the upcoming 33rd CBP Annual Conference on Sept. 23-25th, in Phoenix, AZ.
References
• Harrison DD. Spinal Biomechanics: A Chiropractic Perspective. National Library of Medicine #WE 725 4318C, 1982-97.
• Harrison DE, Cailliet R, Harrison DD, Janik TJ, Holland B. Centroid, Cobb or Harrison Posterior Tangents: Which to Choose for Analysis of Thoracic Kyphosis? Spine 2001; 26(11): E227-E234.
• Harrison DE, Janik TJ, Harrison DD, Cailliet R, Harmon S. Can the thoracic kyphosis be modeled with a simple geometric Shape? The results of circular and elliptical modeling in 80 asymptomatic subjects. J Spinal Disord Tech 2002; 15(3): 213-220.
• Harrison DD, Harrison DE, Janik TJ, Cailliet R, Haas JW. Do alterations in vertebral and disc dimensions affect an elliptical model of the thoracic kyphosis? Spine 2003;463-469.
• Fon GT, Pitt MJ, Thies AC Jr. Thoracic
• kyphosis: range in normal subjects. AJR 1980;134(5):979-83.
• Harrison DE, et al. How Do Anterior/Posterior Translations of the Thoracic Cage Affect the Sagittal Lumbar Spine, Pelvic Tilt, and Thoracic Kyphosis? Eur Spine J 2002;11:287-293.
• Harrison DE, Colloca CJ, Keller TS, Harrison DD, Janik TJ. Anterior thoracic posture increases thoracolumbar disc loading. Eur Spine J 2005; 14:234-242.
• Kiefer A, Shirazi-Adl A, Parnianpour M. Synergy of the human spine in neutral postures. Eur Spine J 1998; 7:471-479.
• Glassman SD, Bridwell K, Dimar JR, Horton W, Berven S, Schwab F. The impact of positive sagittal balance in adult spinal deformity. Spine 2005;30:2024-2029.
• Berthonnaud E, et al. Analysis of the sagittal balance of the spine and pelvis using shape and orientation parameters. J Spinal Disorders & Techniques 2005;18(1):40-47.
• Vaz G, Roussouly P, Berthonnaud E, Dimnet J. Sagittal morphology and equilibrium of pelvis and spine. Eur Spine J 2002; 11(1):80-87.
• Vialle R, Levassor N, Rillardon L, Templier A, Skalli W, Guigui P. Radiographic analysis of the sagittal alignment and balance of the spine in asymptomatic subjects. J Bone Joint Surgery 2005;87Am:260-267.
Introduction More and more, Chiropractors are becoming interested in rehabilitation of the abnormal cervical lordosis due to its potential relationship with a number of patient health disorders.1-3 Chiropractic techniques often recommend the use of both in office equipment as well as supplementation of at home orthotics for rehabilitation of the abnormal cervical lordosis in appropriate cases,4 while other chiropractors use at home orthotics as the primary means of the rehabilitation of the cervical lordosis. There are a number of home devices to choose from and not enough information on when it is and is not appropriate to use these devices for a given patient presentation. In the present article, I would like to discuss the appropriate use of two common corrective cervical orthotic devices aimed at rehabilitation of abnormal cervical curvatures by presenting appropriate indications and contra-indications for the use of these devices.
Non-Compression 3-Point Bending Cervical orthotics provoke a passive 3-point bending force that is generally well tolerated by most patients, as it does not apply compression to the cervical column during patient application. Patient size and the specific abnormality of the cervical lordosis influence the size and choice of what type of cervical orthotic is appropriate for a specific patient. For example, the amount of anterior or posterior head translation dictates the size of the cervical orthotic to be used, however the shape in the cervical lordosis determines the location of the peak of the device (C6-T1, C4-C6, or C2-C4). There are three primary placements of this cervical orthotic, but only the lower cervical/upper thoracic placement will be discussed. Figure 1
Indications for the Cervical Orthotic Lower Neck Placement: Upper thoracic/lower cervical placement. This placement of the orthotic will cause significant posterior head translation unless the large device is used. A lower cervical placement will increase the upper thoracic curve and increase the overall cervical lordosis. Specifically, this placement should be used for straightened or kyphotic lower cervical segments with loss of upper thoracic kyphosis and anterior head translation of approximately ≤ 40mm. (Figure 1) Contra-indications for the Cervical Orthotic: Quite simply put, the contra-indications for this cervical remodeling orthotic device would be the opposite of the indications listed above and many are the indications for the compression-extension wedge below.
Compression-Extension Remodeling Wedge The compression extension cervical orthotic device is a common tool available in the chiropractic profession today with several brands on the market. (Figure 2) The device creates the combination of posterior head translation, cervical extension, and compression force down the long-axis of the spine. Patients must be screened for tolerance to this position and loading; canal stenosis would be contra-indicated for this device. Problematically, the compression extension wedge also creates an anterior translation of the thoracic spine and an extension of the mid-upper thoracic kyphosis. Typically speaking, the wedge only comes in one size (adult) and, thus, patient selection must be considered when using these devices; pediatric cases don’t fit well on this.
Indications for the Compression-Extension Wedge: The compression-extension wedge will correct-reduce anterior head translation with loss of the cervical lordosis. The patient’s posterior vertebral body margins (black dashed-line) must be well anterior of the ideal cervical lordosis (red-line after Harrison et al.2). Head translation forward ≥ 25mm and up to ≈ 70 mm typically responds well to this device. However, the patient must also have posterior thoracic translation and increased mid- and upper-thoracic kyphosis, as the wedge will cause an opposite effect. Figure 2
Contra-indications for the Compression-Extension Wedge: Quite simply put, the Contra-Indications for these cervical remodeling orthotic devices would be the opposite of the indications for those listed above and many are the indications for the non compression three-point-bending devices.
SUMMARY All home cervical corrective orthotic devices, such as the two shown herein, have indications and contra-indications for appropriate patient application. The cervical corrective orthotic should be fit to the following patient presenting conditions: 1) their symptomatology and severity of spinal arthritis/disc disease, 2) their ability to perform specific movements, 3) their presenting posture of the head and thoracic region, 4) their configuration of the cervical curvature, 5) the presence of any unstable segments, and 6) their configuration of the mid-upper thoracic kyphosis. I hope this presentation assists in your delivery of effective at home devices for rehabilitation of the abnormal cervical lordosis.
Dr. Deed will be presenting a comprehensive, contemporary review of this topic at the upcoming 32nd CBP Annual Conference on Sept. 24-26th, in Scottsdale, AZ. Deed E. Harrison, D.C. is President CBP Seminars, Inc., Vice President CBP® Non-Profit, Inc., Chair PCCRP Guidelines, Editor—AJCC.
References 1.Harrison DE, Betz J, Ferrantelli JF. Sagittal spinal curves and health. JVSR 2009 July 31, pp 1-8. 2.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. 3.McAviney J, Schulz D, Richard Bock R, Harrison DE, Holland B. Determining a clinical normal value for cervical lordosis. J Manipulative Physiol Ther 2005;28:187-193. 4.Harrison DE, Harrison DD, Haas JW. CBP Structural Rehabilitation of the Cervical Spine. Chapters 2 & 6. CBP Seminars, 2002; pgs:147-151. ISBN 0-9721314-0-X.
This year marks the coming of validation for the Upper Cervical Chiropractic techniques. Upper Cervical Chiropractors have appeared on mainstream television programs such as Good Morning America, The Montel Williams Show, and Discovery Health Channel, and our own Dr. Marshall Dickholtz Sr. won the ICA Chiropractor of the Year. Some would say the timing is perfect, including several prominent doctors and researchers in the medical field. The National Upper Cervical Chiropractic Association (NUCCA) has spearheaded this movement with the publishing of a hypertension study in a mainstream medical journal (Journal of Hypertension) and is experiencing a growing awareness in the chiropractic and medical world. Recently, Dr. Bruce Bell, a medical doctor from Chicago, stood before 225 NUCCA chiropractors and chiropractic students and discussed how important correcting the atlas subluxation is to the world and how we should be prepared for a greater interest from the health care field in general and increased awareness from the general public.
Posterior to Anterior Thoracic Spinal Adjusting in the Scoliosis Patient Is Contraindicated by Spinal Biomechanics
by Dennis Woggon, DC, B.Sc.
It would make sense to understand normal spinal biomechanics when putting adjustive forces into the spine, especially in a complicated spine such as a scoliosis. It seems that spinal biomechanical forces are frequently ignored when it comes to spinal adjustments and manipulation.
The sagittal spine should have a lordotic cervical curve, a kyphotic thoracic curve and a lordotic lumbar curve. It is accepted that a loss of cervical lordosis will eventually result in a loss of lumbar lordosis.
The question is what does this loss of cervical and lumbar lever arms have on the thoracic spine? There is a reciprocal influence of the lever arms in the spine. A loss of cervical curve will exert posterior to anterior forces on the thoracic spine. This will cause a dipping of the thoracic spinous processes and a slight elevation of the vertebral body. This will manifest as anterior dorsal saucering or Poettenger’s Saucering.
The thoracic vertebra are somewhat fixed by the rib heads in flexion and extension. Flexion and extension of the thoracic vertebra is not a normal motion, but lateral flexion and rotation, as a coupled motion, is a normal motion. When there is a posterior to anterior leverage force on the thoracic vertebra, Poettenger’s Saucering develops to a point and then the thoracic spine will buckle laterally.
It has been known for a number of years that scoliosis is accompanied by a hypokyphosis.
"Thoracic hypokyphosis with increasing axial rotational instability is claimed to be a primary factor for the initiation of Idiopathic Scoliosis."1
Rigo states, ". . . thoracic lordosis is the predominant component of the disease."2
This is further magnified by Winter, who also seems to indicate that the Harrington Rods add to the problem. "The idiopathic cases usually exhibit a flattening of the sagittal curves, which had further deteriorated when the Harrington technique was used."3
DeJong took a historical perspective stating, "A clinical, cadaveric, biomechanical and radiological investigation of the pathogenesis of idiopathic scoliosis indicates that biplanar asymmetry is the essential lesion. When median plane asymmetry (flattening or, more usually, reversal of the normal thoracic kyphosis at the apex of the scoliosis) is superimposed during growth, a progressive idiopathic scoliosis occurs. Idiopathic kyphoscoliosis cannot and does not exist, from the mildest cases in the community to the most severe cases in pathology museums."4
Dickson agrees and sees the possibility of reversal in stating, "Idiopathic scoliosis (IS), which is substantially a three-dimensional deformation of a spine, causes not only lateral curvature and axial rotation of vertebral column, but also lordotisation of vertebrae in structural curve extension. In an effect, physiological thoracic kyphosis diminishes or even disappears. Method of asymmetric trunk mobilization in strictly symmetric positions, according to Dobosiewicz, not only deteriorates progression of IS or even reduces lateral curvature, but also significantly rebuilds physiological thoracic kyphosis in cases of IS accompanied by straight back."5
In comparison groups, Inoue found, "Those patients who had scoliotic deformity with typical vertebral rotation only in thoracic spine (ST group), showed significant decrease compared to normal persons in thoracic kyphosis, but no difference in lumbar lordosis. However those changes in sagittal curvature were not found in FT group patients, who had scoliotic deformity without vertebral rotation. In conclusion, it is not the frontal curvature but the vertebral rotation which influenced the sagittal curvature of spine in patients with idiopathic scoliosis."6
In a clinical study, a fourteen-year-old patient presented with a descending Cobb angle of 36, 56 and 45 degrees (Figure 1).7
The patient’s posture and X-rays (Figures 2 & 3) revealed a loss of cervical lordosis and forward head posture. The lateral thoracic X-ray demonstrated a hypokyphosis of 18 degrees (Figure 4).
By re-establishing the normal sagittal curves, the scoliosis has been reduced in nine intensive office visits (Figure 5).8
The correct adjustment force for this would be an anterior dorsal adjustment and not a P-A adjustment.
It would appear that a loss of the cervical lordosis can cause an anterior dorsal saucering resulting in a lateral bending motion of the thoracic spine. Based on this, posterior to anterior thoracic adjusting in these areas would appear to be contraindicated. This would also apply to the scoliosis patient or the potential scoliosis patient in regard to P-A thoracic adjusting as well as adjusting on the "high side of the rainbow."
1. Sagittal configuration of the spine in girls with idiopathic scoliosis: progressing rather than initiating factor. Rigo M, Quera-Salvá G, Villagers M. Elena Salvá Spinal Deformities Rehabilitation Institute, Vía Augusta 185, 08021 Barcelona, Spain. Stud Health Technol Inform. 2006;123:90-4.
2. Excessive thoracic lordosis and loss of pulmonary function in patients with idiopathic scoliosis. Winter RB, Lovell WW, Moe JH. Bone Joint Surg Am. 1975 Oct;57(7):972-7.
3. Sagittal plane correction in idiopathic scoliosis. de Jonge T, Dubousset JF, Illés T. University of Pécs, Faculty of Medicine, Department of Orthopedic Surgery, Pécs, Hungary. Spine. 2002 Apr 1;27(7):761.
4. The pathogenesis of idiopathic scoliosis. Biplanar spinal asymmetry. J Bone Joint Surg Br. 1984 Jan;66(1):8-15. Dickson RA, Lawton JO, Archer IA, Butt WP 1984.
5. Influence of method of asymmetric trunk mobilization on shaping of a physiological thoracic kyphosis in children and youth suffering from progressive idiopathic scoliosis. Stud Health Technol Inform. 2002;91:348-51Dobosiewicz K, et al, Department of Rehabilitation, Medical University of Silesia, Katowice, Poland 40-635 Katowice, ul. Ziolowa 35/37,
6. The sagittal curvature of spine in idiopathic scoliosis—its morphological features and the correlation among sagittal and frontal curvatures and rotation of apical vertebra. Inoue K. Nippon Seikeigeka Gakkai Zasshi. 1985 May;59(5):505-16.
7. Pictures and X-rays used with patient and guardian’s permission. 2008
8. CLEAR Institute and CLEAR Scoliosis Center, St. Cloud, MN.
Last month we discussed the problems associated with hypolordotic lumbar postures as well as the protective effects of a healthy lumbar lordosis. I want to use this month's column to cover the same ground as it pertains to the cervical spine. Patients walk into your office every day with complaints related to the cervical spine. Of the many symptomatic presentations we commonly handle as chiropractors, a sizeable percentage can be either directly or indirectly attributed to loss of the normal cervical lordosis. Hypolordotic and/or kyphotic cervical postures are associated with a wide range of problems. Conversely, a healthy cervical lordosis provides a large measure of protection to the neck. Consider the following fun facts.
Fact: Loss of the cervical lordosis predisposes the capsular ligaments to higher risk of injury in the event of trauma.1
Habitual carriage of the neck in a straightened or kyphotic posture pretensions both the capsular ligaments and the ligamentum flavum. This pre stressing effect can have severe ramifications in the event of sudden neck trauma such as whiplash injuries. A 2005 study in the Journal of Biomechanics, found that trauma to patients with such postures may elongate the capsular ligaments "by up to 70%", "induce laxity to the facet joint", and predispose the neck to "accelerated degenerative changes over time." The authors concluded that "abnormal spinal curvatures enhance the likelihood of whiplash injury and may have long-term clinical and biomechanical implications." In the event your patient is involved in an auto accident following care in your office, and statistically the average American is in a car accident about once every six years, the success or failure of your corrective care efforts to restore the lordosis may well determine how severely they are injured. Fact: Hypolordotic/kyphotic neck postures predispose the discs to injury while a healthy lordosis provides a protective effect. We know that flexed (hypolordotic) postures result in potentially damaging disc mechanics. The anterior disc space is narrowed as the posterior disc space is widened with the result that the nucleus is forced posterior against the tensioned posterior annulus (See Fig. 2). White and Panjabi have stated that “the risk of disc failure is greater with tensile loading as compared to compressive loading.” 2 Restoration of the cervical lordosis provides protection to the posterior annulus by removing/reducing tensile stress to the posterior disc fibers and restoring normal weight bearing so as to discourage posterior migration of the nucleus toward the vital neural elements in the spinal canal and IVF (See Fig.3). Fact: Normal lordosis is vital for the neck to have maximum resilience to compressive loads. A 2001 study in the Journal of Neurosurgery, looked at the effects of cervical posture on the loadbearing ability of the cervical spine.3 During compressive loading, the straight spines failed through the anterior motor unit (disc and vertebral bodies) while the lordotic spines supported more of the weight on the posterior joints thereby sparing the disc and vertebral bodies. The authors concluded "that a loss of a lordosis increases the risk of injury to the cervical spine following axial loading." In conclusion, the normal cervical lordosis is a highly protective posture for your patients. Due to the limits of space, I haven't even touched here on the protective effects of cervical lordosis to the spinal cord and nerve roots, the vertebral bodies, and to the reduction of a wide range of symptomatic complaints. If you aren't already incorporating postural rehab methods into your treatment plans, you are leaving your patients wide open for future problems. And there's really no reason for that to happen. Effective treatment options are easily mastered, require no changes in your adjusting technique, and are affordable to the point of being downright cheap.
Dr. Mark Payne is president of Matlin Mfg., a manufacturer and distributor of postural rehab products since 1988. A more detailed report on this subject is available for free, as well as a FREE SUBSCRIPTION to Postural Rehab...electronic newsletter on corrective chiropractic methods. CALL 334-448-1210 or email
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.
References:
Stemper BD, Yoganandan N, Pintar FA. Effects of abnormal posture on capsular ligament elongations in a computational model subjected to whiplash loading. J Biomech 2005 Jun; 38(6) 1313-23.
White and Panjabi, Clinical Biomechanics of the Spine. J.B. Lippincott Company 1978. Pg. 153.
Oktenoğlu T, Ozer AF, Ferrara LA, Andalkar N, Sarioğlu AC, Benzel EC.J Neurosurg. 2001 Jan;94 (1 Suppl) 108-14 Effects of cervical spine posture on axial load bearing ability: a biomechanical study.
Problematically, some of this normal subject data is contaminated with subjects that should not be considered healthy. For one example, Fon, et al.,5 presented thoracic kyphosis measurement in 316 “normal subjects” aged 2-77 yrs. Their definition of normal was: “…while the general status of some of these patients was not optimal, it was assumed that the patients were sufficiently fit to be ambulatory….”
Harrison and colleagues3 presented average geometric models of the thoracic kyphosis (T1-T12, T2-T11, and T3-T10 segments were modelled) as a segment of an ellipse using pooled data from 80 normal subjects’ lateral thoracic radiographs. Figure 3 shows the average elliptical model of the segments T1-T12.3
endplate of T12. The minor axis to major axis ratio was computed to be 0.69.4 Figure 4 shows this optimized elliptical model in a template form that can be used for any height of a patient.
Contra-indications for the Compression-Extension Wedge:
Dr. Mark Payne is president of Matlin Mfg., a manufacturer and distributor of postural rehab products since 1988. A more detailed report on this subject is available for free, as well as a FREE SUBSCRIPTION to Postural Rehab...electronic newsletter on corrective chiropractic methods. CALL 334-448-1210 or email 
