Deed E. Harrison, DC President CBP Seminars, Inc. Vice President CBP Non-Profit, Inc. Chair PCCRP Guidelines Editor—AJCC Private Practice-- Eagle, ID, USA
INTRODUCTION
Since my graduation from Chiropractic College (Life Chiropractic College West) in 1994, I’ve spent much of my 20 years in the clinical and research trenches attempting to understand and improve abnormalities of the cervical lordosis in patient populations. I've personally been involved in many scientific research investigations developing and discussing the evidence for the connection between the cervical lordosis in human health, disease, and spine disorders. In the current article, a brief but focused literature review on the cervical lordosis will be presented; then recommended in office vs. home care methods with the available evidence will be discussed.
The Adult Lordosis
The adult cervical lordosis has received considerable attention in the spine literature; in 1996, both average and idealized values and geometric shape of the cervical lordosis were reported. The average adult cervical lordosis was 34° ± 9° between C2-C7 posterior vertebral body lines.1 In a follow-up paper in 2004, my colleagues and I2 modeled the adult cervical lordosis (using a curve fitting method known as the least squares error) as a piece of a circle from C2-T1. Furthermore, we demonstrated statistically significant differences in adult cervical lordosis between normal subjects, acute neck pain subjects and chronic neck pain subjects.1,2
The Figure 1. below indicates the representative normal cervical lordosis.
Figure 1. ©Copyright Harrison CBP Seminars. Reprinted with permission.
Literature Review Linking Lordosis to Disorders
Multiple investigations have been published seeking to understand the association, correlation, or the predictive value of an altered cervical lordosis in different health conditions compared to normal controls. To this end, the majority of these studies have found correlation and predictive validity of the lateral cervical radiographic alignment to a variety of health related conditions including:
- Acute and chronic neck pain.2-5
- Headaches.5-8
- Mental health status.9
- Whiplash associated disorders (WAD).10-18
- Degenerative joint disease (DJD).19-30
- Temporal mandibular joint disorders.31
- Range of motion and segmental motion patterns.32-34
- Respiration syndromes.35-39
- Radiculopathy.40,41
- Increased probability for soft tissue injury under impact and inertial loads.42-46
Oppositely, a few investigations have found that the lateral cervical alignment measurements do not correlate to and predict the findings in the above 10 categories.47-52 However, many of these investigations have been found to be internally flawed and detailed reviews of these studies have been performed.53-57 Thus, it should be obvious that the number (45 studies listed above) and the quality of investigations finding a correlation between the lateral cervical radiographic alignment and the conditions in the above 10 categories is superior to the few negative correlation studies. Over the past 20 years, I personally have concluded that the lateral cervical radiographic alignment has positive correlation and predictive validity for the above 10 categories of spine disorders and health conditions.
In Office Methods vs. At Home Care
Historically, the Chiropractic profession has a long history of interest in attempting to improve or correct alterations in cervical lordosis. Problematically, though many outcome investigations have been performed using a variety of chiropractic procedures, most of the traditional methods of Chiropractic procedures have been shown to have limited success at restoration of the cervical lordosis. Still, taken as a collective whole, these reports indicate that patients benefit by reduced pain, improved range of motion, decreased disability levels, and increased health status following chiropractic procedures that improve the cervical lordosis to near normal values.58-85
- § In Office Cervical Extension Traction Methods
According to the literature, Chiropractic BioPhysics® or CBP® Technique cervical extension traction procedures are the best available methods for conservatively, consistently and statistically, improving the cervical lordosis. This 'best' evidence exists as 4 clinical control trials (3 non-randomized and 1 randomized) where cervical extension traction treatment methods were added to and compared against various other chiropractic and physical procedures in treated patients versus control group populations.58-61 From this data, extension traction procedures have been found to produce average lordosis corrections between 7° (in more severely injured population) and 18° (in typical chronic neck pain populations) following approximately 36 treatment sessions over the course of 9-12 weeks duration.
Though cervical extension traction procedures can be considered part of the standard of care for rehabilitation of the cervical lordosis; its wide spread implementation into Chiropractic practices has yet to occur. The likely reasons for this lack of widespread implementation for extension traction is multi-factorial and would include: increased square footage office space needed, increased staff to support implementation, increased patient time in the office, and lack of wide spread technical training for proper applications with indications and contraindications for the various methods. See Figure 2. for in office traction methods.
Figure 2. Various in office cervical extension traction methods. ©Copyright Harrison CBP Seminars. Reprinted with permission.
- § Home Corrective Orthotics
The use of home corrective orthotic (cervical curve traction) devices as a supplementation to in office treatment programs aimed at rehabilitation of abnormal cervical curvatures has a considerable history in Chiropractic practice. The use of 'at home' cervical extension traction orthotics would seemingly solve several of the key issues with implementation of in office traction methods. Home devices tend to be easier for the patient to use, they are less cumbersome, they are more affordable, and they are likely to be more tolerable. However, at least three main concerns with 'at home' based cervical orthotics must be acknowledged:
There are several different types of home based cervical lordosis corrective orthotics. In Figure 3. a couple of the more popular devices are depicted. Below, I've elected to focus on the cervical denneroll orthotic as it is one of the most applicable, easy to use, and effective (when used properly) home based orthotics today.
Figure 3. Various at home cervical extension traction orthotics: posture regainer, compression extension unit, and cervical denneroll. ©Copyright Harrison CBP Seminars. Reprinted with permission.
The Denneroll Cervical Orthotic
The cervical Denneroll orthotic device is a simple, yet complex, pillow-like device engineered with curves, angles, and ridges extrapolated, in part, from the CBP evidence based cervical spinal model. Adrian Dennewald, DC (Denneroll Industries in Sydney, Australia) is the developer and owner of the Denneroll orthotic line. In 2008, Dr. Adrian partnered with Chiropractic BioPhysics in an effort to expand the Denneroll product line, to develop proper indications and contraindications for patient care, and to research-test the effectiveness of the Denneroll in improving the cervical lordosis and patient conditions.
Personally, I was interested in the Cervical Denneroll device as a solution for a low-stress, comfortable mirror-image® traction orthotic to supplement CBP in office care at home.
To date, the cervical Denneroll, has been tested in a number of case reports and 2 randomized clinical trials. It's been found to improve the cervical lordosis in different patient populations by 7°-14°.86-91 Thus, the Denneroll orthtoic has been shown to be able to effectively improve the abnormal lordosis of the cervical spine in properly selected cases. Today, the cervical Denneroll products are used worldwide by over 5000 Chiropractors from North America and Australia to the UK, Europe, Asia, and several other international locations.
- Indications for the Denneroll
The Denneroll currently comes in 3 sizes (adult large, adult medium, and pediatric or small) and can be used in many patient conditions and cervical curve configureations. There are three primary placements of the Denneroll cervical orthotic device shown in Figures 4-6. The Denneroll placement should be consistent with both the shape of the cervical curve and the amount/type of sagittal head translation correction that is desired.
- Upper thoracic/lower cervical placement- C7-T2
This placement of the Denneroll will cause significant posterior head translation, it 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 ≤ 40mm. See Figure 4.
Figure 4. Abnormal cervical curvatures that fit the inclusion criteria for the application of the Denneroll corrective orthotic in the lower cervical region. These spines must have: • Normal or a mild loss of the upper thoracic kyphosis; • Loss of the lower cervical curve (with or without kyphosis); • Anterior head translation of approximately ≤ 40mm. ©Copyright Harrison CBP Seminars. Reprinted with permission.
Mid-low cervical placement - C4-C6. This placement of the Denneroll will cause slight posterior head translation; however if the larger Denneroll device is used on a small statured individual then it will create some anterior head translation. The cervical spine should have straightened or kyphotic mid cervical regions (apex of the curve). See Figure 5. In cases with significant posterior head translation, as in Figure 5A, the large Denneroll orthotic should be used and a towel can be placed under the Denneroll to increase the height if needed.
Figure 5. Abnormal cervical curvatures that fit the inclusion criteria for the application of the Denneroll corrective orthotic in the middle cervical region. These spines must have: • Normal or a loss of the upper thoracic kyphosis; • Straightening or apex at the mid-cervical curve; • Slight anterior head translation of approximately ≤ 15mm; • In B with Posterior head translation the LARGE Denneroll should be used with a small towel under it to increase height. ©Copyright Harrison CBP Seminars. Reprinted with permission.
Upper to mid cervical placement- C2-C4. This placement of the Denneroll is used for posterior head translation with straightened or kyphotic mid-upper cervical curves. This position allows extension bending of the upper cervical segments while causing slight anterior head translation. See Figure 6. In cases like Figure 6A with significant posterior head translation, where the posterior vertebral bodies are behind the ideal red curved line,7 the large Denneroll orthotic should be used. While in Figure 6B, the small Denneroll should be used.
Figure 6. Abnormal cervical curvatures that fit the inclusion criteria for the application of the Denneroll corrective orthotic in the upper cervical region. These spines must have: • Close to normal lower cervical curvature; • Straightening or apex at the C2-C4-cervical segments; • In B, normal head translation of approximately ≤ 15mm. Here the SMALL Denneroll is used to not create anterior head posture; • In A with Posterior head translation the LARGE Denneroll should be used to create anterior head translation. ©Copyright Harrison CBP Seminars. Reprinted with permission.
- Contra-indications for the Denneroll:
Quite simply put, no spine orthotic is indicated or should be used in every case presentation. There are both known and proposed risks for extension traction and extension positioning procedures in spine care. The treating -prescribing clinician should perform an examine in every case and perform proper tolerance testing with the patient prior to releasing the patient to use the Denneroll device at home.
Here's a basic proposed list of contra-indications for Denneroll orthotic patient use:
- Moderate to severe mid to upper thoracic hyper-kyphosis;
- Large, rigid anterior head translations that does not reduce with extension;
For a more complete list of contraindications for the Denneroll device, please consider the cervical Denneroll training DVD series available at this link: http://chiropractic-biophysics.myshopify.com/collections/denneroll-traction-devices/products/denneroll-box-set-all-5-dvds-cervical-thoracic-lumbar-compression-extension-and-scoliroll-training-videos
Simple Case Report for Understanding Home Care Implementation.
In this simple / brief case presentation, we have a female that was involved in a frontal collision crash. The subjective complaints were typical complaints seen with whiplash injuries, such as neck pain, sclerotome pain referral to lower neck and upper thoracic spine from probable facet joint injury, headaches, etc. In this case, the patient elected simply not to perform in office traction due to time constraints. In office care consisted of initial coarse of acute care diversified adjusting for 6 visits, then CBP Mirror Image® drop table and instrument based adjustments and Exercises. The patient having such a magnitude of kyphosis, was started as soon as possible with the Denneroll orthotic (on her 7th visit) starting 2x/day at 1 minute and building up to two sessions of 10 minutes, once in morning, and again once at night. Once this goal was achieved, after 2 weeks (4 weeks after injury), she was placed on 1 session of use per day working up to 20 minutes daily. Her initial x-ray was performed on 10/6/2009 then the next post was actually only 2 weeks later, this time on a Digital Motion X-Ray (DMX), dated 10/20/2009. DMX was chosen as she persisted with headaches and any evidence of ligamentous laxity can be documented. Notice in just 2 weeks of use, the cervical kyphosis is starting to reduce! After 40 sessions of home use, and 36 visits total treatments, with her symptoms and outcome studies showing her nearing pre-injury status, she was prescribed another follow up DMX. The changes on this final follow up x-ray (3-24-2010) were quite amazing as evidenced below in Figure 7.
A Recommendation for In Office & At Home Exercise Warm Up
It is usually more difficult to re-establish a cervical lordosis in patients that present with a kyphotic cervical curvature and moderate to advanced degenerative joint disease (DJD). These patients usually complain of chronic cervical pain, muscle rigidity and restricted motion. Many of these patients spend much of their day in cervical flexion or anterior head translation and have lost the capacity to truly extend and move their cervical spines. Long term relief for these patients is generally not possible without some form of effective structural and soft tissue rehabilitation.
It is for the above reasons that we typically will recommend that patient performs a series of strengthening and flexibility exercises for their cervical spine prior to performing either in office cervical extension traction or at home Denneroll cervical extension traction. Most often we use the Pro-Lordoic Neck Exerciser™ developed by Dr. Don Meyer of California. This device was modified after the cervical neck strap used and taught for this exercise by myself in the CBP Cervical Rehab Seminars for the past several years. Typically we will have the patient perform various forms of cervical exercises using this exercise band for approximately 5-10 minutes prior to performing or using cervical extension traction devices. The Pro-Lordotic exerciser is shown in Figure 8.
A simple series of exercises with this band are shown on the below youtube links; however, it should be obvious that the treating clinician should select the proper exercises for the individual patient:
Figure 8. The Pro-Lordotic Neck Exerciser™ is a progressive resistance neck exercise device that tractions the normal lordosis into the cervical spine while active extension exercises of the entire cervical spine are performed during the five minute, structural/postural corrective, home or in-office treatment session. For product ordering information see the following link: http://chiropractic-biophysics.myshopify.com/collections/exercise-equipment/products/pro-lordotic-neck-exerciser ©Copyright Harrison CBP Seminars. Reprinted with permission.
SUMMARY
Discussions of the cervical lordosis has a long history in the spine literature. While nothing is without controversy, the majority of past and present research reports indicate that the cervical lordosis plays a pivotal role in human health, many spine disorders, and several health disorders. While in office treatment programs combining cervical extension traction procedures should be considered the gold standard for consistent, predictable improvements in patients suffering from abnormalities of the cervical lordosis, at home based corrective cervical spine orthotics should be implemented as well. The cervical Denneroll is one of the most applicable, easy to use, most cost effective, and outcome effective home based cervical extension orthotics on the market today. Clinicians should be aware of the indications and contraindications for at home usage of this device. I hope this presentation assists in your delivery of effective patient intervention in the office and with supplementation of at home devices.
Note:
For more information on the Denneroll Orthotic, please visit http://www.idealspine.com/cervical-dennerol/
For information on becoming a denneroll provider in the USA / Canada please visit http://chiropractic-biophysics.myshopify.com/pages/signup.
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