20 I Winter 2019 www.anjc.info TECHNIQUE Council OUR HEALTH The center piece of Chiropractic care is the adjustment, a specific form of spinal manipulation applied to correct spinal dysfunctions. Within a short period of time most Chiropractors recognize that how an adjustment is delivered has as much an effect on producing positive health changes as what is being adjusted. The “adjustment with that some- thing extra”, as BJ Palmer phrased it, is a result of three main factors – neurological, mechanical, and psychological. Neurological Effects When administering a spinal manipulation the following neurological responses have been observed in varying degrees: • Relaxation of hypertonic spinal musculature • Decreased dysafferentation • Mechanoreceptor stimulation (Afferentation) • Neuromodulation of pain • Decreased vertebrogenic dysautonomia • Myotomal stimulation • Nerve root decompression • Endogenous endorphin release • Decreased inflammatory mediators • Release of dural tension • Supraspinal effects • Spinal learning (Neuroplasticity) • Vestibular effects • Downregulation of central facilitation Mechanical Effects Applying mechanical forces to the connective tissues and articulations of the spine results in a sequela of reactions depending on the pathology and integrity these structures. Some of those demonstrated include: • Release of entrapped synovial folds or meniscoids • Disruption of intra-articular or periarticular adhesions • Reduction of intervertebral disc pathomechanics • Unbuckling of displaced motion segments • Decreased joint pressure • Facet joint gapping • Increased intervertebral motion • Improved bone mineral density and bone mineral content Psychophysiological Effects The combination of the setting that the adjustment takes place in, the intention and confidence of the doctor, the expectations of the patient, and the communications exchanged can have a profound effect on the outcome. A variety of mechanisms facilitate this, including: • Psychological changes in mood, emotion, and behavior • Improved self-care • Changes in pain perception and tolerance • Autonomic and endocrine responses • Mirror neuron stimulation • Opiate and endorphin sensitivity in the patient • Conditioning Improving The Adjustment Based on the above factors, here are 10 research influenced ways we can improve our adjustments: 1.  End range manipulations produce the most mechanore- ceptor stimulation. 2.  Level specificity is important, but specific adjustments have been shown to be located to 3 segments (the targeted site and the adjacent vertebral units) rather than one. 3.  The site of an adjustment often doesn’t correlate with the site of pain or inflammation. 4.  Speed counts. The faster the HVLA impulse or thrust, the more afferentation and muscle spindle stimulation occurs. 5.  Long lever HVLA techniques are more effective for producing cavitation. 6.  Cavitation is not necessary for a neurological effect of manipulation, but has more immediate relaxation effects on the para-spinal muscles. 7.  There is a “sweet spot” for the amount of force applied that gives the most beneficial effect. Too much or too little preload or bodyweight is counter-productive to a good adjustment. 8.  For the “sensitive patient” use low-force techniques to start. Graduate to more dynamic manipulations when you can (if you can). 9.  Adjustments work better coupled with corrective exer- cise. 10.  The adjustment, especially with patients who have chronic conditions or have multiple complications, is part of an overall plan of care and not a stand-alone procedure. Dr. David Graber, DC, CCSP, is the chairperson of the ANJC Council on Technique and Clinical Excellence. He maintains a private practice in Parsippany, NJ. He can be reached at: DrDavidGraber@gmail.com. How Chiropractic Adjustments Work By Dr. David Graber Chair, Council on Technique and Clinical Excellence