Many benefits of chiropractic adjustments occur not only from correcting what we’re adjusting, but how we are delivering the adjustment itself. The act of spinal manipulation has physiological effects on the human body.
A recent review of the mechanisms of these effects was published this month by Hinkeldey. Below is a summary of some of these.
Summary of neurophysiologic effects of manual therapy:
- Significant reduction in blood and serum level cytokines in joint-biased manual therapy
- Changes of blood levels of b-endorphin, anandamide, N-palmitoylethanolamide, serotonin
- Endogenous cannabinoids increases
- Joint-biased manual therapy is speculated to bombard the central nervous system with sensory input from the muscle proprioceptors
- Afferent discharge
- Motoneuron pool activity
- Changes in muscle activity
- Joint-biased manual therapy to the lower extremity of rats after capsaicin injection. Functional MRI of the supraspinal region quantified the response of the hind paw to light touch after the injection. A trend was noted toward decreased activation of the supraspinal regions responsible for central pain processing.
- Autonomic responses
- Opioid responses
- Expectation of effectiveness of manual therapy is associated with functional outcomes
- Joint-biased manual therapy is associated with improved psychological outcomes
- Dopamine production
- Central nervous system
Source: Nathan Hinkeldey, Casey Okamoto, Jamal Khan,Spinal Manipulation and Select Manual Therapies: Current Perspectives, Physical Medicine and Rehabilitation Clinics of North America, Volume 31, Issue 4, 2020, Pages 593-608, ISSN 1047-9651, ISBN 9780323790925, https://doi.org/10.1016/j.pmr.2020.07.007.