It is true that there are a few statements in the ensuing outlines for which we cannot as yet find the anatomical or physiological proof. But it must be remembered that anatomists and physiologists have never studied the body with a knowledge of the subluxation theory to aid them in gaining perspective and that Chiropractors, as a class, have not yet delved deeply enough into anatomy and physiology to extract all the available and illuminating information from them. Ofttimes the facts we value most are most obscure in the texts because to others they seem least important. But they are there. Armed with information concerning Chiropractic facts it is probable that the scientist of the future will corroborate all of our clinical findings of today and emphasize the rational explanations of them.

In the following tables it has been found best to insert in parentheses the capital letter (P) to call attention to any statement in support of which we have gathered less than all three forms of admissible evidence and which is therefore as yet presumptive. It is well, however, for the practitioner to be careful lest he regard too lightly such presumptive statements. Unless there is very strong and reasonable ground for such presumption or a general belief in its correctness all mention of it is omitted. Those labelled presumptive are merely so indicated because they have not yet been proven and not because they have failed to serve as a convenient and useful guide to adjustment. For each presumption offered there is either clinical or anatomical justification but not both.

SPECIAL NERVE CONNECTIONS

This section does not purport to state with any degree of completeness the various nerve-paths by which spinal vertebrae come into relation with all, or nearly all, the peripheral organs of the body. It merely points out some of the more interesting and important connections, some of the paths which serve to explain the common effects of vertebral adjustment. It is not expected that this resume of the subject will be more than suggestive to the student; certainly it cannot, in so brief a space, be a complete exposition.

Outline of Nerve System

Let us begin with the observation that almost every organ of the body, including the central nerve organs themselves, may be adversely affected by spinal subluxation impinging spinal nerve axons at their exit from, or entrance through, intervertebral foramina, or by spinal subluxation producing direct impingement upon some part of the sympathetic system and similarly interfering with its power to functionate.

The Nerve System may be divided into two great divisions, the central axis and the peripheral system which distributes nerve energy from, and brings stimuli to, the central axis. The central axis consists of the brain and spinal cord; the peripheral system of 12 pairs of nerves attached to the brain and having exit (except the eighth) through foramina in the base of the cranium, 31 pairs of spinal nerves emerging through intervertebral foramina whose parts are movable upon each other (except the foramina for sacral and coccygeal nerves), and an intricate system of sympathetic fibres and ganglia arranged in a double chain of ganglia in front and at the sides of the vertebral column, three great prevertebral plexuses, the cardiac, coeliac, and hypogastric, and numerous scattered ganglia and communicating cords which bind the ganglia together and connect them with spinal or cranial nerves and with the periphery.

The peripheral system is somewhat complex and numerous intercommunications are established by which nerve impulses originating in the central axis and leaving by one part of the peripheral system may exercise a controlling influence over another part. Plexuses, or intertwinings of nerve axons, are so numerous and complicated that it is difficult to follow each set of nerve stimuli from their origin to their final destination and effect without considerable study.

Direct Distribution of Spinal Axons

The spinal nerve axons, taken as a whole, establish paths between the motor gray of the ventral horn of the spinal cord and all voluntary muscles of the body below the head except the trapezius and sternomastoid, partially innervated by the eleventh cranial, and between the sensor cells of the dorsal spinal gray and gracile and cuneate nuclei of the medulla on the one hand and the sensor end organs in skin and mucuous membrane, muscles, tendons, and joints on the other. The ventral cornu receives impulses from the cortico-spinal axons of the direct pyramidal, crossed pyramidal, rubrospinal, and other smaller tracts which bring the spinal gray under the direct voluntary domination of the volitional centers in the brain or of the indirectly voluntary pathway through the cerebellum. The spinal nerves are the direct media for motion of the body or its parts in relation to its environment. The sensor gray of the cord is similarly in communication with the conscious sensation area in the cerebrum and with the cerebellum by way of the dorsal tracts of the cord, the lemnisci, and the cerebellar peduncles.