Chiropractic and Spinal Allignment
or Cervical Curve

This section was compiled by Frank M. Painter, D.C.
Make comments or suggestions to   Frankp@chiro.org

Jump to:    Introduction      Spinal Allignment and Curve Articles

---

Other
Pages:        Nutrition Section            Chiropractic Research           ChiroZine

                    Antibiotic Abuse              Safety of Chiropractic            Iatrogenic Injury

                    Stroke & Chiropractic     Problems With Placebos       Kids Need Care Too!

                    Patient Satisfaction         Forward Head Posture          Cost-Effectiveness

                    Disc Herniation                Subluxation Complex            Headache Page

                    Alternative Medicine Approaches              Outcome Assessment

Chiro.Org is proud to support the FCER and the ICPA and their continuing research into the health benefits of chiropractic care. Please offer them your financial assistance!

Introduction

Structure and Function Our spine is a “structural” unit. There are 4 curves to the spine. Loss of structural integrity and/or normal function of the spine is the basis for the evolution of the vertebral subluxation. Abnormal stresses occur in the facets, discs and supporting tissues when normal motion of the spine is impaired. Chiropractic analysis should be aimed at locating the specific segments which are subluxated, as well as providing the means to “free” those segments.

The normal cervical lordosis (which extends from C1 to T2) should have a 17-24 cm. radius , based on the patient's height. This is easily measured with the AcuArc ruler. Kim Christensen D.C. in his book “Clinical Chiropractic Biomechanics” states, “Spinal biomechanical stability requires an optimal lordotic structure. The lordotic cervical & lumbar spine are the basis of the spine's ability to resist axial stressors.”   A resistance factor in mechanical structure is expressed by the formula:

R = C² + 1

where   R = resistance to axial pressure and   C = the number of curvatures.   Thus the spine's ability to resist axial pressure, taking into account the cervical, thoracic and lumbar curves is:

R = 3²+ 1 = 10

If we lose the cervical or lumbar curves, the formula is reduced to:

R = 2² + 1 = 5

Thus, a reduced cervical curve can result in a 50% reduction in the strength of the spine!


To define the cervical curve of the spine with a compass:

1.     Dot the posterior inferior aspect of C1's anterior arch. (see Figure 2)

2.     Dot the anterior superior aspect of the vertebral body of T2.

3.     Set your compass for the distance between these 2 points. This length defines the “chord length” of the curve. Now, swing arcs back with the compass set, using the chord length to locate the point which will describe the optimum spinal curve. (See Figure 1) Then set the compass on the radius center-point, and use the same chord length to strike the radius of the cervical curve. (See Figure 2) Note that ALL the vertebra should be on this line, with the radius between 17-24 cm., depending on patient height.


                       Figure 1

Figure 2

All segments should be on Georges's (posterior body) line. There should be an even spacing between each spinous process. Positioning of the head and spine should also be assessed for anterior head placement (also known as Forward Head Posture). The posterior arch of Atlas should be centered in the space between occiput and the C2 spinous process. If C1's posterior arch “crowds” occiput, it is labelled as an “inferior” Atlas. If it crowds C2, it is labelled “superior”. The normal Atlas Plane line would be 18-24 degrees superior to the bottom of the film. A line under the bottom of the C2 body (Whitehorn's line) should be level with the floor.

Spinal Allignment and Cervical Curve Articles

   The Forward Head Posture Page
           Persistent forward head posture (a.k.a “hyperkyphotic posture”) puts compressive loads upon the upper thoracic vertebra, and is also associated with the development of Upper Thoracic Hump, which can devolve into Dowager Hump when the vertebra develop compression fractures (anterior wedging).   A recent study found this hyperkyphotic posture was associated with a 1.44 greater rate of mortality.


   The Use of Flexion and Extension MR in the Evaluation of Cervical Spine Trauma: Initial Experience in 100 Trauma Patients Compared with 100 Normal Subjects
Emerg Radiol 2002 (Nov);   9 (5):   249—253
The cervical spines of 100 consecutive uninjured normal asymptomatic adults and 100 adult accident victims following rear low-impact motor vehicle accidents were evaluated using rapid T2-weighted MRI. Injured subjects were evaluated during the subacute period, at 12 to 14 weeks after injury. The "normal subjects" showed: Loss of normal cervical lordosis (hypolordosis) in 4% (4 of 100) patients: Range of motion of 50° flexion, and 60° extension; and asymptomatic disk herniations were observed in 2% (2 of 100) patients.

In the subacute post-traumatic subjects, there was a loss of the normal segmental motion pattern, with hypolordosis in 98% (98 of 100) patients. Range of motion was restricted, quantified as 25° flexion and 35°; and disk herniations were observed in 28% of the patients. The authors conclude that flexion and extension MR can be a valuable adjunct examination in the evaluation of patients in the clinical setting of subacute cervical spine trauma.


   Effects of Abnormal Posture on Capsular Ligament Elongations in a Computational Model Subjected to Whiplash Loading
J Biomech 2005 (Jun);   38 (6):   1313—1323
Although considerable biomechanical investigations have been conducted to understand the response of the cervical spine under whiplash (rear impact-induced postero-anterior loading to the thorax), studies delineating the effects of initial spinal curvature are limited. Results from the present study, while providing quantified level- and region-specific kinematic data, concur with clinical findings that abnormal spinal curvatures enhance the likelihood of whiplash injury and may have long-term clinical and biomechanical implications.


   Determining the Relationship Between Cervical Lordosis and Neck Complaints
J Manipulative Physiol Ther 2005 (Mar);   28 (3):   187-193
In a study of 277 lateral cervical x-rays, patients with lordosis of 20° or less were more likely to have cervicogenic symptoms (P < .001). The association between cervical pain and lordosis of 0° or less was significant (P < .0001). The odds that a patient with cervical pain had a lordosis of 0° or less was 18 times greater than for a patient with a noncervical complaint. Patients with cervical pain had less lordosis and this was consistent over all age ranges.


   Cervical Kyphosis is a Possible Link to Attention-deficit/hyperactivity Disorder
J Manipulative Physiol Ther 2004 (Oct);   27 (8):   e14 ~ FULL TEXT
A 5-year-old patient was diagnosed with ADHD and treated by a pediatrician unsuccessfully with methylphenidate (Ritalin), Adderall, and Haldol for 3 years. The patient received 35 chiropractic treatments during the course of 8 weeks. A change from a 12 degrees C2-7 kyphosis to a 32 degrees C2-7 lordosis was observed after treatment. During chiropractic care, the child's facial tics resolved and his behavior vastly improved. After 27 chiropractic visits, the child's pediatrician stated that the child no longer exhibited symptoms of ADHD. The changes in structure and function may be related to the correction of cervical kyphosis.


   Cervical Spine Curvature During Simulated Whiplash
           Clin Biomech 2004 (Jan);   19 (1):   1-9
           Average peak lower cervical spine extension first exceeded the physiological limits (P<0.05) at a horizontal T1 acceleration of 5 g. Average peak upper cervical spine extension exceeded the physiological limit at 8 g, while peak upper cervical spine flexion never exceeded the physiological limit. In the S-shape phase, lower cervical spine extension reached 84% of peak extension during whiplash. Both the upper and lower cervical spine are at risk for extension injury during rear-impact. Flexion injury is unlikely.


   Cervical Spine Geometry Correlated to Cervical Degenerative Disease in a Symptomatic Group
J Manipulative Physiol Ther 2003 (Jul);   26 (6):   341-346
Chiropractors have long maintained that loss of spinal curvature was a sign of loss of function that leads to degenerative joint disease. This paper discusses "5 geometric variables from the lateral cervical spine that were predictive 79% of the time for cervical degenerative joint disease."


   Is the Sagittal Configuration of the Cervical Spine Changed in Women with Chronic Whiplash Syndrome? A Comparative Computer-assisted Radiographic Assessment
J Manipulative Physiol Ther 2002 (Nov);   25 (9):   550-555
The whiplash group showed a decreased ratio between the lower versus upper cervical spine but comparisons between groups were not statistically significant. The whiplash group was in a significantly more flexed position at the C4-C5 level compared with the asymptomatic group (P =.007). The reliability measures have to be strengthened to render these results definitely conclusive.


   Sagittal Alignment of Cervical Flexion and Extension: Lateral Radiographic Analysis
Spine Journal 2002 (Aug 1);   27 (15):   E348–E355
The results suggest that alterations in the static alignment of the cervical curvature cause alterations in the dynamic kinematics of the cervical spine during cervical flexion-extension. This information should aid in the interpretation of kinematic studies of the cervical spine.

Return to the NECK PAIN Section

Return to the CHIROPRACTIC RESEARCH Page

Return to the CHIROPRACTIC RESEARCH RESULTS Page

Since 8-15-2002

Updated 4-14-2008