Adjusting Tools

Head to Head: Traction Vs. Flexion/Distraction

Jay Kennedy, DC; Dennis Anthony, DC


Mechanical Traction As Chiropractic Treatment

By Jay Kennedy, DC

Traction therapy (decompression) as a primary treatment for herniated discs is well known in physical therapy and chiropractic. About 40 percent of PTs report using traction as a treatment for herniated discs, particularly with nerve involvement. As many as 30 percent of DCs use traction systems. According to an ACA survey, up to about 60 percent of DCs use F/D, primarily to affect disc and nerve conditions. Some manufacturers argue that lumbar traction is not the same as disc decompression, even though virtually every authority (including the FDA) concludes otherwise. Traction in the axial plane is disc decompression. There are no "real" or "true" decompression machines, protocols or pull patterns; these are marketing tactics.

The distinct benefits of traction are: reduction of intra-discal pressure (IDP) and enhanced circulation; widening of foramina/spinal canal and reduced HNP size; variable body positions adaptable to a directional preference; mechanoreceptor modulation; reproducibility of pull factors and force; and regional mobilization without added segmental pressure.1

The possibility of negative IDP is ultimately determined not by a machine or the specific "pull" but by the condition of the disc(s) and patient position. Gay, et al. concluded, "Distraction appears to predictably reduce nucleus pressure. The effect is dependant on the health of the disc."2 Adams, et al. points out that neither IDP changes nor disc migration can be accurately determined in degenerative discs.3 Normal (hydrostatic) discs will "decompress" when gravity is eliminated in either hyper-flexion or extension recumbent postures (morning flexion stiffness and diurnal height changes prove this). However, when gravity is eliminated and axial tension is applied, the effect is markedly increased. Not coincidently, the FDA requires manufacturers to include the phrase: "Decompression, that is unloading due to distraction and positioning."

The 2008 Spine study also suggests it is distraction (axial) that creates the changes in IDP. The addition of flexion (extension) had no added effect on compressive stresses in the posterior annulus.2 That is, adding flexion had no benefit in terms of disc pressure changes. Practically speaking, having used F/D for some 20 years, I have found that the best results have always followed the least amount of flexion and a greater amount of distraction. The flexion component can become an unwieldy artifact and may account for some F/D reactions. I tend to choose axial traction in the majority of cases where IDP manipulation (decompression) is warranted and a directional preference or radicular symptoms exist.

Some clinicians suggest that the hands-on aspect of F/D is superior to a harness and that it is more "specific," allowing for variable segmental adjustments. However, the notion of chiropractic specificity has been tackled by more illustrious authors than myself, and I'd suggest flushing out that research before finalizing an opinion. It may be better to stretch an entire spinal region since it is often impossible to accurately determine which disc is the site of pain. Some demonstrate no hydrostatic pressure, others seem near normal, some have herniation symptom, while others don't. More concentration to a particular region (upper vs. lower) is plausible in both traction or F/D, but exact levels and pin-point accuracy is doubtful. Also muscle contraction during F/D approaches 5-10 percent of MVC. This may be an untenable artifact in some cases. It's also important to recognize that hyper-mobility of lower lumbar segments may be prevalent in symptomatic individuals. Adding directed pressure may be perturbing.

Cyriax said: "Traction is expedited bed rest without the disuse side effects." If decompression is valuable, axial traction is certainly a reasonable treatment option. However accurate patient classification remains a key ingredient for success. Decompression, therefore, is the potential disc-related outcome achieved during axial traction/distraction. The prime contingency is an intact and hydrostatic disc (unusual with excess dessication/degeneration). Movement of fluid and nutrients can expedite healing in many cases, although the actual mechanism of pain relief is virtually impossible to determine due to the myriad of overlapping effects (stretch receptors, regional mobilization, placebo effect etc.).

It is difficult to get past the intuitive value of axial traction or F/D. If compression is a source of pain shouldn't axial stretch be, at least in part, a viable solution? The answer is yes, it often is a viable part of a successful strategy for compression syndromes...just not always! And just not with the predictability that we demand. However a highly adaptable traction system affords the clinician the best possibility of aligning objective findings and clinical prediction variables to the patient. Ease of use, adaptability and its intuitive value give traction a distinct place in chiropractic practice.

References

  1. PT Pract 2005 Jan;21(1).
  2. Gay RE, Ilharreborde B, Zhao KD, et al. Stress in lumbar intervertebral discs during distraction: a cadaveric study. Spine 2008 Nov-Dec;8(6):982-90.
  3. Adams MA, Burton K, Dolan P, Bogduk N. Biomechanics of Back Pain. Edinburgh: Churchill Livingston, 2006.

[pb]Advantages of Flexion/Distraction Tables

By Dennis Anthony, DC

Motorized flexion/distraction tables are multi-purpose, adjustable treatment tables designed to apply traction and distraction forces to spinal structures with continuous passive motion. This process is used to gently stretch and traction the spine, intersegmental discs and surrounding soft tissue. Spinal conditions treated on a motorized flexion/distraction table include:

  • general back pain
  • sciatica
  • scoliosis
  • facet syndrome
  • spondylosis
  • joint disorders
  • spondylolisthesis

Since the spinal segments are being decompressed and stretched with continuous passive motion created by the motor of the table, a lower adjustment force is required to decrease a joint fixation. Less physical requirement by the practitioner will lead to less physical disabilities that plague chiropractic physicians in their later years of practice. The doctor's hands are free to motion palpate and observe. The motor driving the caudal section of the table provides the practitioner the freedom to evaluate and observe spinal joint motion of the bones, ligaments, tendons and muscles. This provides a valuable diagnostic tool for treating spinal conditions.

There are two major advantages for the patient. Therapeutic stretches applied before a spinal adjustment relax the patient and stretches targeted soft tissue. This leads to a comfortable spinal adjustment for the patient. Using the distraction movement of the table to decompress the disc and surrounding tissues requires less corrective forces applied by the practitioner for joint correction. Less corrective forces leads to a more comfortable adjusting procedure for the patient.

In addition to increased joint motion, motion-assisted stretches lengthen muscle fibers that have contracted from disuse or excessive use; restores muscle flexibility after injury; assists in removing natural wastes like lactic acid from muscles; increases disc and connective-tissue flexibility; restores muscle balance; reduces joint inflammation; relieves stress and tension; and improves posture.

Motion adjusting occurs during the down stroke of the table's caudal section in combination with a corrective thrust. The downward motion distracts and separates the spinal joint segments, creating movement of the connective tissue. The application of a specific chiropractic force at the same time the intersegmental joint is in motion accelerates joint movement.

Learning how to use motorized flexion/distraction and motion adjusting in your practice will require time with the use of the table. Follow these steps, and in a short time you will be comfortable applying your specific technique to motion.

Familiarize yourself with all the features of the table. Practice starting and stopping the table in various positions. Use the table to motion-palpate the spinal segments in long-axis flexion/distraction. Start applying motion assisted stretches. Use this time to get comfortable with the speed of the table. Most tables have variable speed control. Start off slowly and gradually increase speed to your comfort level.

Once you're comfortable with the motion of the table and applying spinal stretches, gradually begin motion-assisted adjusting. Start with the upper thoracic spine and work your way down to the sacrum. Remember that with motion, a less-corrective force will be required by the practitioner. Start lightly until you become comfortable with motion-assisted adjusting.

If you do not have a motorized flexion/distraction table, contact your local chiropractic colleges or other chiropractors in your area who have them. Ask if they will allow you to spend some practice time with them. In a short time, you will see the benefits of motion-adjusting for you and your patients.

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