Spinal Manipulation: Pros, Cons, Mechanisms of Action

Discs never slip

Pros: There is evidence that suggests that spinal mobilizations a.k.a. manual therapy a.k.a. chiropractic adjustments a.k.a. high-grade joint play, can have interesting neurophysiological (mind-body) effects, albeit by not actually structurally altering the spine in any way.  Vertebrae don’t shift or slide or “sublux” spontaneously.   Jason Silvernail has aptly stated that, “Spinal mobilization engages several pain relief mechanisms in the body primarily through neuromodulatory and endocrine pathways – not through affecting structure of the joints or effecting connective tissue through direct structural change.”

Mechanisms of Action of Spinal Mobilization: http://www.ncbi.nlm.nih.gov/pubmed/26751060/

“Evidence suggests that spinal mobilizations cause neurophysiological effects resulting in hypoalgesia (local and/or distal to mobilization site), sympathoexcitation, and improved muscle function. Mobilizations have no effect on temperature pain threshold. Three of four studies reported reduction in spinal stiffness, heterogeneous in location and timing. There is limited evidence (one study in each case) to suggest that mobilizations produce increased nociceptive flexion reflex threshold, improved posture, decreased concentration of substance P in saliva, and improved sway index measured in cervical extension. Evidence does not support an effect on segmental vertebral movement.”

Cons: At about 13:15 – Harriet Hall describes how cervical (neck) manipulation is involved in causing tears in the delicate lining of the vertebral arteries, which can cause clots, which can lead to strokes.  One estimate posits that 20% of basilar strokes, or 1300 strokes in the U.S. per year, are caused by cervical spinal manipulation…and this could actually be an under-reporting of the numbers, because neurologists might not inquire about prior cervical manipulation upon meeting a patient.

Conclusion:  Manipulation might be useful in helping patients get out of pain, and return to function, however, cervical (neck) manipulation should probably be avoided.