How the Chiropractic Adjustment Reduces the Need for Opioids
In order to explain how chiropractic adjustments reduce the use for opioid medications we must understand how the two different mechanisms work. Opioid analgesics decrease pain transmission to the brain by activating the descending inhibitory pain mechanism.
Nerve fibers from the periaqueductal gray within the midbrain and raphe nuclei housed in the medulla control endogenous (our body manufactures) opioid containing interneurons within the dorsal horn of the spinal cord. Opioids directly inhibit afferent nerve transmission by binding to mu-opioid receptors presynaptically and postsynaptically within the dorsal horn of the spinal cord. The ascending pathways for pain stimuli are inhibited and pain relief is provided to the patient.
In terms of the chiropractic adjustment, the sound of an adjustment is the decompression of one or more synovial joints, usually facet joint(s) within the spine.
This stimulus is transmitted afferently via mechanoreceptors that stimulate with dorsal root ganglion and ascend by way of the spinothalamic tract toward the thalamus and eventually reach the somatosensory cortex where the feeling of the adjustment is perceived by the brain. From there, a few different processes happen.
A. Limbic or emotional response (1) (laughter, happiness, sadness, fear)
B. Stimulation of the norandergenic system - immediate fight of flight response to the adjustment (2)
C. Release of serotonin - sustained feeling of euphoria and lowers certain smooth muscle activation (3)
D. Stimulation of the descending inhibitory pain mechanism-decreased response to nociception (4)
In summary, the chiropractic adjustment releases endogenous endorphins similar to those after administration of oral opioid analgesics. It temporarily stimulates the fight or flight response from excitation of the sympathetic nervous system and releases serotonin for a longer lasting effect of diminished nocicepion specifically at the dorsal root ganglion. The ladder effect taking place via the same neurological pathway of opioid analgesics, the descending inhibitory pain mechanism.
For certain conditions, chiropractic care could alleviate the usage for opioid analgesics. It has been shown that administration of chiropractic care reduces opioid usage by as much as 57%.