Activator Methods: Examining From The Ground Up

By James W. Gudgel, D.C.

One axiom I learned in chiropractic college is "gravity is king," and all you have to do to experience this is to pass out while standing and see where you end up. The center of gravity, according to Schafer,1 is "located in the region just anterior (about 1-1/2 inches) to the top of the second sacral segment."

The body’s stability comes from the pelvis, which is supported by the lower extremities, and the whole system is stabilized by muscular control. That is why we end up as a "heap of bones" on the floor when we pass out and our muscular control is turned off.

Plotke2 aptly points out that the spinal column is a single column of central weight that must be transferred into two columns (the hips when sitting and the legs when standing). This transfer of weight occurs in the lumbosacral region.

We chiropractors know that spinal and pelvic misalignments lead to faulty movement patterns. If you drive your car with the front wheels out of alignment, it leads to premature tire wear and reduced gas mileage. Similarly, faulty spinal and pelvic movement patterns lead to premature muscular fatigue, increased energy consumption, degenerative joint changes, fissures (cracks) in the annulus of a disc and aberrant nerve impulses along the afferent, efferent or internuncial pathways.

My job is to discover these biomechanical faults (subluxations) and correct them through adjustments, complementing them with ancillary procedures as indicated. As a Logan College graduate and Activator practitioner, I understand the necessity for examining not only the pelvis and full spine, but also all of the structures below the pelvis that help support it.

Investigating Causes
Of course, we quiz the patient to discover what they "did" to injure their back so that we will have something to put in the daily notes. Sometimes the injury is due to trauma (e.g., falls, auto accidents, etc.) to an area of the body, but often there is no history that would explain the patient’s current problem.

Liebenson3 correctly states that, "Most low back injuries result from trivial rather than frank trauma." Eventually, misalignments occur, and then a seemingly "trivial" event produces a major back problem.

Over the past decade, I have witnessed more emphasis on rehabilitation principles and procedures in the chiropractic profession, and I think this is beneficial and necessary. Numerous authors have stated that support and stability to the low back comes primarily from the muscles (Figure 1). If you read the various publications and journals that cross your desk, you will note the increasing frequency of articles concerning spinal rehabilitation procedures. Additionally, there have been numerous articles on how faulty biomechanics in the lower extremity lead to problems in the support system of the pelvis and spine. An entire section of the Activator textbook4 is devoted to lower extremity problems.

As an Activator Instructor, I teach full spine and extremity analysis procedures that locate subluxations causing or contributing to the patient’s problems. By systematically examining the whole patient, one can find, and then correct, all extremity, pelvic and spinal subluxations. The subluxation correction is accomplished through the use of a hand-held, mechanically-assisted device known as the Activator Instrument (Figure 2).

The current instrument, a third-generation model, has three settings, each with a specific force and thrust distance for various areas of the spine and extremities (Figure 3). This new instrument is the result of spinal stiffness and frequency resonance research,5 and the thrust of the new instrument stimulates a much wider range of receptors in and around the joint being adjusted, as well as producing bone movement that has been shown to be equal to that of much higher force techniques.6,7

Analytical Procedures
In Activator analysis, we speak of a "facilitated lesion." The Activator leg check (Figure 4) locates the subluxations responsible for these "facilitated lesions" so that they can be "de-facilitated." The body’s sensory-motor systems repeatedly respond to trauma and everyday stresses via muscular reflexes. Subluxations interfere with these muscular reflexes. These reflexes may be depressed, and the muscles will then not respond appropriately during movement. Or the reflexes may be over-stimulated, causing habitual muscular contractions that the patient may not be able to relax voluntarily.<V>8<V> Research has shown that these contractions may continue uninterrupted even during sleep.<V>9<V> Coordinated and synergistic muscular movement requires a continuous input of sensory information.<V>8<V> This is essential in preventing the subluxation from recurring or new ones from developing.

The mechanism of action that corrects the subluxation, de-facilitates the "facilitated" lesion, and "re-sets" the sensory-motor reflexes appears to involve altering the discharges from the various proprioceptive tissues of the joint area, such as the Golgi endings in tendons, muscle spindle cells and nerve endings in the skin, fascia, ligaments, joint capsule and disc.10

These receptors report joint position and motion, direction of motion and velocity of motion. It is thought that the Activator adjustment allows normalization of joint function by restoring the proper function of the feedback loop between the sensory and motor divisions of the central nervous system. This appears to be accomplished through both the bone movement and receptor stimulation produced when the Activator Instrument thrust is applied to a subluxation.

In conclusion, the patient must be examined from "the ground up" to correct problems in the lower extremities that interfere with pelvic stability.

References
1. Schafer, Clinical Biomechanics, Musculoskeletal Actions and Reactions, Williams and Wilkins, 1983.

2. Plotke, "The Power of the Center," Physical Therapy Forum, Jan. 14, 1994.

3. Liebenson, C., "What Is the Mechanism of Injury for the Low Back?", Dynamic Chiropractic, April 17, 2000.

4. Fuhr, Arlan, et al., Activator Methods Chiropractic Technique, Mosby, 1997.

5. Keller, et al., "Mechanical and Muscular Behavior of the Lumbar Spine in Response to Dynamic Posteroanterior Forces," Proceedings of the 26th Annual Meeting of the International Society for the Study of the Lumbar Spine, Kona, Hawaii, June, 1999, p. 136A.

6. Nathan, et al., "Measurement and Analysis of the In Vivo Posteroanterior Impulse Response of the Human Thoracolumbar Spine," JMPT, 1994; 17(7):431-44.

7. Maigne, et al., "Highlighting of Intervertebral Movements and Variations of Intradiscal Pressure During Lumbar Spine Manipulation," JMPT, 2000; 23:531-36.

8. Hanna, Somatics, Reawakening the Mind’s Control of Movement, Flexibility and Health, Addison-Wesley Publishing Co., 1988.

9. Budzynski, "Brain Lateralization and Rscripting," Somatics, 3(2).

10. Korr, "Proprioceptors and Somatic Dysfunction," JAOA, 74, 638-50.

About the authors: James W. Gudgel, D.C., a 1982 Logan College of Chiropractic graduate, is a senior instructor in Activator Methods and manages a private practice. For more information, write to him at Chiro-Plus, P.A., 821 E. Bridge St., Redwood Falls, MN 56283; call (507) 637-8649; or e-mail to drgudgel@rconnect.com

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