Background and objectives: Several theories have been put forth in attempts to explain the possible mechanisms by which patients presumed to be suffering from any of a variety of internal organ diseases are occasionally found to respond quickly and dramatically to therapies delivered to purely somatic structures (e.g., spinal manipulation). The purpose of this review is to examine the scientific bases upon which these sorts of clinical phenomenaight be interpreted.
Data sources: A review was conducted of over 350 articles that have appeared in the scientific literature over the last 75 years. Initially, a MEDLINE search was performed; however, because of the variability of indexing terms employed by investigators within a wide variety of biomedical disciplines, most of this literature had to be located article by article.
Data synthesis: At present, there have been no appropriately controlled studies that establish that spinal manipulation or any other form of somatic therapy represents a valid curative strategy for the treatment of any internal organ disease. Furthermore, current scientific knowledge also fails to support the existence of a plausible biological mechanism that could account for a causal segmentally or regionally related "somato-visceral disease" relationship. On the other hand, it has now been firmly established that somatic dysfunction is notorious in its ability to create overt signs and symptoms that can mimic, or simulate (rather than cause), internal organ disease.
Conclusions: The proper differential diagnosis of somatic vs. visceral dysfunction represents a challenge for both the medical and chiropractic physician. The afferent convergence mechanisms, which can create signs and symptoms that are virtually indistinguishable with respect to their somatic vs. visceral etiologies, need to be appreciated by all portal-of-entry health care providers, to insure timely referral of patients to the health specialist appropriate to their condition. Furthermore, it is not unreasonable that this somatic visceral-disease mimicry could very well account for the "cures" of presumed organ disease that have been observed over the years in response to various somatic therapies (e.g., spinal manipulation, acupuncture, Rolfing, Qi Gong, etc.) and may represent a common phenomenon that has led to "holistic" health care claims on the part of such clinical disciplines.