Historical Overview and Update on Subluxation Theories
SOURCE: J Chiropractic Humanities 2010 (Dec); 17 (1): 22–32
By Howard Vernon, DC, PhD
Manual therapy has, arguably, best been described by a Polish medical manipulation practitioner, Arkuszewski,  as “a mechanical therapy with reflex effects.” The phrase mechanical therapy can be further characterized by noting that it is performed in the musculoskeletal (MSK) system. The phrase reflex effects can be further qualified, at the very least, to indicate that these are “health-beneficial.” Therefore, a revised version would read as follows:
“a manually-performed mechanical therapy to the MSK system with health-beneficial reflex effects.”
This formulation also provides a basis for describing the primary disorder posited by chiropractic theory: subluxation. Recognizing that, for chiropractic, the subluxation has always been viewed as the “thing for which adjustment (manual therapy) is done,” a first-pass definition of subluxation, a la Arkuszewski, would be:
“a mechanical problem in the musculoskeletal system with health-deleterious reflex effects.”
Since the founding of chiropractic and the other manual therapy professions, 2 fundamental issues have vexed us:
- What kind and location of mechanical problem in the MSK system qualifies as a subluxation (or any of the other terms used as synonyms within and outside of chiropractic)?
- What kind of health-deleterious effects are specifically associated with subluxation?
The author recognizes that numerous others have attempted to review the subluxation concept, including recent excellent reviews by Gatterman,  Peters,  and Ebrall.  These previously published discussions are not reviewed here. What follows is a nonsystematic overview of selected developments in the profession that have addressed these 2 questions.