December 2010 Newsletter from Malik Slosberg, DC, MS

Cramer GD, DC, PhD, Henderson C, DC, PhD. Zygapophyseal Joint Adhesions After Induced Hypomobility. JMPT 2010; 33:508-18.

Roy RA, DC, MSc, Boucher JP, PhD, FACSM, Comtois AS, PhD. Inflammatory response following a short-term course of chiropractic treatment in subjects with and without chronic low back pain. Journal of Chiropractic Medicine. 2010; 9, 107–114.
Today is December 18 and here are two new studies. They are both directly related to chiropractic care. They cover two different topics. The first is a follow-up of a series of studies by Charles Henderson, DC, PhD, and Greg Cramer, DC, PhD that evaluates the progression of degeneration as a result of hypomobility in the lumbar spine zygapophyseal joints of rats. It includes photomicrographs which, for the first time, demonstrate the progression of intra-articular adhesions. The second study is a valuable addition to the recent literature on chiropractic care and it's influence on the immune system. I hope you find the summaries and commentaries of interest and applicable to patient education and clinical practice.

Cramer GD, DC, PhD, Henderson C, DC, PhD. Zygapophyseal Joint Adhesions After Induced Hypomobility. JMPT 2010; 33:508-18.

This study is to determine if connective tissue adhesions (ADH) develop in lumbar zygapophyseal (Z) joints after experimentally induced intervertebral hypomobility (segmental fixation). 

Methods: Using a rat model, 3 contiguous lumbar segments (L4, L5, L6) were fixed with surgically implanted, vertebral fixation devices (spinal attachment units) via the use of metal linking bars. Z joints of experimental rats (17 rats, 64 Z joints) with 4, 8, 12, or 16 weeks of induced hypomobility were compared with Z joints of age-matched control rats (23 rats, 86 Z joints). Tissue was photomicrographed. A grading system was developed to identify small, medium, & large adhesions.

Results: Small & medium ADH were found in rats from all study groups, but large ADH were found only in rats with 8, 12, or 16 weeks of experimentally induced intervertebral hypomobility. The number of medium & large ADH per joint increased with the length of experimentally induced hypomobility in rats with 8 & 16 weeks of induced hypomobility. 

Conclusions: Hypomobility results in time-dependent ADH development within the Z joints. ADH development may be relevant to spinal manipulation, which could theoretically break up Z joint intra-articular ADHs.

Commentary: This new study uses a refinement of a protocol developed by the same researchers first published in 2004. In 2007 these authors demonstrated that resultant long-term hypomobility from the use of a vertebral fixation device leads to degeneration which continues to progress even after the fixation device has been removed. In other words, lesions due to hypomobility are progressive and have increasing biomechanical consequences. This basic animal research lays the groundwork for the use of chiropractic adjustments to restore motion and possibly prevent degeneration from progressing. In this new study, the inclusion of photomicrographs (pictured below) demonstrate the development of intra-articular adhesions and the time it takes for them to mature and enlarge over 4 to 16 weeks. This progression, once again, provides the foundation for the use of high velocity low amplitude spinal manipulation in order to disrupt these adhesions in the early stages in order to restore and preserve range of motion and to prevent the degeneration which ensues when there is loss of motion. 

Small_Adhesion
Large_adhesion


Roy RA, DC, MSc, Boucher JP, PhD, FACSM, Comtois AS, PhD. Inflammatory response following a short-term course of chiropractic treatment in subjects with and without chronic low back pain.  Journal of Chiropractic Medicine. 2010; 9, 107–114.

Background: LBP is often associated with an inflammatory process & the production of several proinflammatory cytokines including interleukin-6 (IL-6) & C-reactive protein (CRP). IL-6 is the main mediator of the acute phase of proinflammatory cytokines. IL-6 results in a marked increase in liver cell synthesis of CRP.

Methods: This study evaluates pre- & post-intervention measures from blood samples detecting proinflammatory cytokines interleukin 6 (IL-6) & C-reactive protein (CRP) after a series of 9 chiropractic manipulations employing an Activator adjusting instrument and using the Activator protocol. Segments from T12-L5 were evaluated in 10 chronic low back pain (CLBP) patients (=/>3 mo) and manipulative thrusts were applied according to the Activator protocol and compared to a control group (no treatment) of 10 healthy subjects. 

Results: 9 manipulations (using Activator Methods & instrument) in CLBP patients caused the mediators of inflammation to present a normalization response, that is a reduction in blood levels. Both IL-6 & CRP levels were reduced toward the values in the control grp. IL-6 & CRP were elevated in CLBP patients at preintervention, but post-intervention differences were smaller suggesting that 9 manipulations were capable of attenuating the inflammatory response. It is plausible that the inflammatory process was  diminished or reversed, but complete healing was not achieved following 2 weeks of treatment. 

Commentary: This study is a valuable addition to a series of studies published by Anita Teodorczyk-Injeyan, PhD & Steven Injeyn, DC, PhD, both researchers at Canadian Memorial Chiropractic College. There is accumulating evidence demonstrating that chiropractic adjustments result in the reduction of inflammatory chemical mediators. These inflammatory cytokines initiate and maintain the inflammatory cascade which results when there is tissue damage. There is a direct association of a reduction in inflammation with a reduction in pain. This anti-inflammatory effect demonstrated with spinal manipulation in recent studies  and confirmed in this paper suggests that there is a complex relationship between the nervous system and the immune system. Systemic somatoautonomic reflex effects following spinal manipulation may modulate immune reactions and be a factor involved in the beneficial responses to spinal manipulation. 

Roy_Inflammatory_response_IL_6_CRP