By Jay Kennedy, DC
Though clinical surveys suggest only a third of DCs use decompression in their offices, they are often highly visible in terms of market presence. “Have it or compete against it” has been a well-worn phrase when promoting decompression, and it remains more true than false today. Most patients are extremely well informed and seek sensible, affordable, rapid solutions for their symptoms. Since diagnosis and treatment of low back pain (LBP), as well as neck pain, continues to defy absolute classification, having a treatment that directly addresses disc compression can be an invaluable investment.
Over the past 25 years, there have been innumerable articles on decompression therapy (axial traction) as a primary chiropractic modality and profit center. Decompression perhaps is the most intuitive and easily explained of all chiropractic interventions for a compressed disc lesion. There is little doubt in most patients’ minds that distraction should, at least temporarily, relieve pain and perhaps hasten disc healing in a way other treatments may not. It’s nontraumatic, relaxing, and often the ideal treatment for the itinerant patient. Additionally, there are numerous patient-education videos and interactive apps that demonstrate disc herniation, degeneration, and the effects decompression exerts. There is a dynamic-disc model that demonstrates a migrating nucleus through an annular tear, allowing direct patient interaction with the compression and distraction effects. These education aids are hugely valuable in motivating and instructing patient compliance and bridging the gap between pay-per-treatment and package-programs.
Over the past decade, we’ve tried our best to create a reasonable and scientific placement of traction within chiropractic using these concepts and incorporating simple classification algorithms and treatment protocols.
Proper classification or subgrouping continues to be one of the most important aspects of physical medicine. This concept uses research and scientific reasoning cues to deduce the “who, where, and when” of adding the therapy. This assures the greatest possible benefit to those most likely to respond. Asking for cash from a patient poorly qualified for treatment increases the risks for dissatisfaction. It’s important that the patient’s movement patterns, directional preference(s), muscle tension, and reactions to distraction be assessed. Further, external-compression bracing and the FABQ (fear-avoidance beliefs questionnaire) play key roles in helping proper classification, as does MRI (though contrary to popular belief, often to a lesser degree).¹
In my 25 years of using and scrutinizing decompression, external pelvic compression (EPC), or what we refer to as form- and force-closure tests, has become indispensable in classification. In fact, I believe a majority of traction candidates are most easily sub-grouped within a few minutes of these reference tests.
These procedures and pretreatment screens are based on a relatively substantial body of research that suggests bracing of the upper and/or lower pelvic ring(s) can reveal important mechanical facts. First, it gives support to the SI joints and supplements form closure.² if ligament laxity is an issue, it improves that. Second, and most pertinent to a chiropractor, there are alterations in “selective muscle recruitment patterns” and lumbopelvic kinematics. ³
Ostensibly, chiropractic is a method of altering central nervous system (CNS) communication and thus movement patterns. When there is a motion glitch, adjusting certainly helps. I have been a proponent of the ATM2, the Stabilizer, and many other motion techniques employed alongside spinal adjusting. However, I have discovered that many of our more complicated patients often defy classification as a motion “disorder” and instead classify as “compression.” Shirley Sahrmann, PhD, has written about this topic in Movement Impairment Syndrome and points out that when realignment/repositioning techniques fail to improve pain, compression is likely the issue.4
Simple predictors exist, such as feeling better when recumbent and standing being less painful than sitting (generally), sitting with lumbar support, and sitting supported with the arms.5,11 When compression is present, it can often override or overwhelm motion classification and give confounding signals.
The benefits of decompression will be distinct and often dramatic in that subgroup, which is often the majority of seriously and chronically pained patients.6
The ability to offer an intuitive, safe, easy-to-administer, unattended, and highly compliant treatment is inestimable in today’s climate. Additionally, from a business perspective, selling treatment packages can be very profitable and reduce office stress. Of course, not all offices are interested in selling package-plans and many continue with the pay-per-treatment option. However, decompression candidates can have more serious conditions that may warrant elongated treatment recommendations.
The benefit of this is a more likely intersection with natural healing and being in better control of the patient in terms of directing proper rehab, ergonomics, and nutrition advice.
Recent research has begun to explore various possible physiologic mechanisms of mobilization and manipulation, and their relationship to pain relief. Preliminary results suggest pain relief may have a relation to disc “fluid diffusion.” MRI analysis reveals that posteroanterior (PA) mobilization, prone press-up, and manipulation all show increased fluid diffusion into the disc after treatment (when that treatment renders at least a 2/10 on the visual analog scale for pain improvement).7 A complex interaction between mechanoreceptors and muscle tension may generate a more conducive environment for fluid inflow. It’s important to keep in mind that axial traction has the most direct and potent effect on fluid diffusion, and therefore may well have a greater potential for disc-pain relief.8 In fact, decompression’s essence is the creation of a centripetal (sucking inward) potential, which drives diffusion through the tissues and endplate.
In contrast to the benefits of extension, some researchers, including Bogduk and McGill, have proposed that there can be a detrimental effect to repetitive extension exercises. This appears to be the case when moderately severe degeneration is present. Recent MRI studies have shown that degenerative discs act much differently to imposed stress and motion than normal or mildly degenerated discs. In fact, posterior nuclear bulging often occurs during extension.9
Excessive back-bending can, in many degenerative disc cases, create delamination of the annulus and foster greater pain and disability. Since manipulation and mobilizations are often extension-based (and often used in conjunction with extension exercises), it’s important to be aware of this. The distinct advantage of axial decompression therapy becomes apparent when these other approaches, such as extension-oriented exercise (or manipulation techniques), fail to help or are untenable.10
- Discogenic, MRI and psychosocial determinates of LBP. Carragee EJ et al. Spine Feb; 5(1) 2005.
- Effects of external pelvic compression on form-closure, force-closure and neuromotor control of the lumbopelvic spine. Armugam A et al. JOPST Aug. 2011.
- Movement Impairment Syndrome. Sahrmann, S. PhD. Churchill Livingstone. 1996.
- Intradiscal pressure variations during motion. Wilke HJ. Clin Bio; 16(1) 2001.
- Discogenic origins of spinal instability. Zhao F et al. Spine Dec; 30(23) 2005.
- Immediate reduction in LBP following lumbar joint mobilization and prone press-up is associated with increased diffusion of water in the L5/S1 disc. Beattie PF et al. JOSPT; 40(5) 2010.
- Stress in lumbar discs during distraction. Gay et al. Spine Nov; 8(6) 2008.
- Dynamic bulging of IVD in the degenerative lumbar spine. Zou J et al. Spine Nov; 34(23) 2009.
- Lumbar extension exercises in conjunction with mechanical traction in the management of a patient with a lumbar HNP. Gagne AR, Hasson M. PTprac May; 26(4) 2010.
- Clinical exam procedures to determine the effects of axial decompression on patients with LBP. Holtzmann et al. JOPST; 42(2) 2012.