Part 14

The causes of the change in the shape, form, and relation of the different segments are functional: the body changes to meet the changing needs of its environment and the steady progressive functional development from one species to another.

When the animal at last assumes the erect position, doing more intricately and intelligently the bidding of a developing and improving central nervous system, the change of position and the force of gravity bring about a gradual downward, or caudad, tendency of the parts of the somatic segments most remote from the spine and of the nerves which supply them.

The nerves, muscles, and bones of the lower extremities change from almost a right angle to an extremely obtuse angle, less obtuse during infancy and more so in the adult. The forelegs become arms and hang at the sides, extending downward from the part of the spine which controls them. The ribs tend more obliquely downward and outward from the spine and the tendency of all the nerves is downward from their attachment to the spinal cord to their emergence from the intervertebral foramina. In the neck and head alone is this rule varied, the tendency of the nerves and some other structures there being to run from the spine either at right angles or upward.

It seems almost symbolic and indicative of the purpose of creation that the body, which is less strong and vigorous in Man than in the lower animals, should tend more and more obliquely downward from its central axis, while the cranium, containing a highly specialized mass of cells and fibres, the organ of Mind, which marks Man’s supremacy in the animal kingdom and is his crowning glory, is reared _above_ the body it dominates.

In all the form changes which mark the growth of the body the organs are arranged to afford the greatest possible economy of space and convenience for use. This perfect and matchless mechanism adapts itself to the changing habits and environments and to the quality and needs of the Mind which inhabits it.

Necessity for Table of Spino-Organic Connection

To the practitioner who is fully equipped with an instantly available knowledge of all the nerve connections in the body and to whom palpation of a subluxation at once suggests its somatic sphere of influence as a weakened or diseased area, or to whom mention of a disease immediately calls to mind the organ, or segment, which is primarily affected and its nerve connection with the spine, any tabulation of spino-organic connection or of diseases and adjustments, for reference, is unnecessary. But the ordinary practitioner finds it difficult to acquire and retain such an array of information and much more convenient to refer to reliable and easily read tables which will supply at once any such information desired.

No specific adjustment is possible without knowledge of the vertebra which controls the part diseased and toward the healing of which the nerve energy should be directed. Specific adjustment without correct diagnosis is of course impossible. And whenever correct diagnosis has been made it is essential that the mind of the Chiropractor should revert to one certain vertebra which he expects to find subluxated as the primary cause of the disease.

Diagnosis is essential in order to find out _what_ organ is the site of the disease, for all disease is primarily segmental. The _location_ of the disease having been determined, a quick reference to a table showing the spinal connection with that location makes specific adjustment possible. The value of specific, as against general, adjustments will be considered under “Practice.”

Method of Investigation

One who wishes to determine for himself the proper specific adjustment for a certain disease must, in order to be able to attach any weight to his conclusions or to announce them with any hope of credence by the scientific world, proceed very much after the following method, which sets down what may be termed “standard test conditions” for research into the spino-organic connection.

He must make a correct diagnosis which serves to determine the nature and location of the disease process. In this he may be greatly aided by vertebral palpation and nerve-tracing, especially in differential diagnosis. Any case which affords less than a quite positively correct diagnosis should be excluded from the test list because any conclusion based on a doubtful diagnosis must itself be doubtful and may be seriously misleading.

He must then ascertain as far as possible the known anatomical nerve connection between the spine and the diseased part. If several connections are known he must decide according to nervous physiology, by recognizing the morbid functions which constitute the disease and learning which nerves control these functions and which must therefore be deranged in order that the disease may exist. I may say right here that to attempt to answer the problems of Chiropractic on the assumption that standard anatomies are incorrect in their statement of nerve connections is as hopeless as the wail of the schoolboy that the answers in his arithmetic are wrong because his sums fail to come out that way.

The investigator must next be accurate in Palpation, selecting the subluxation which would, from his knowledge of the body segmentation, seem most likely to influence the nerves involved, and positively ascertaining the _number_ of the subluxated vertebra. No one who cannot count vertebrae accurately can positively say which vertebra he has adjusted. More than that, no one who _has not_ counted the vertebrae in the special case in question can say which vertebra he has adjusted. No mere regional localization will suffice for scientific investigation.

Correct and accurate adjustment must follow selection of the single vertebra and the adjuster must know that he has used the one special movement, or form of adjustment, which is mechanically right for that kind of subluxation and has so moved the vertebra as to release impingement. Mere movement of a vertebra is not necessarily an adjustment or even a maladjustment; it may be movement without permanent change of relation or release of impingement. (See “Preferable Adjustments,” p. 155.)

There follows the observation of the progress of the case and this must be so careful and accurate that the observer knows to a certainty whether the disease is progressing unfavorably, or favorably, or whether it has been entirely eradicated. He must know the value of every changing symptom, the real meaning of each new development. Every diagnostic method should be at his command for this work. Constant vigilance and constant thought should mark each step of his work.

Finally he must be so cautious and careful in his statements that no doubtful conclusion is allowed to escape from his own mind. We may believe or suspect or hope for proof of our theories but we have no right to state as a fact anything except that which has been proven under the most rigidly guarded scientific test conditions.

Failure to observe any of the precautions mentioned renders worthless the results of investigation. Nothing further than a mere presumption can be based upon research which fails to observe all these rules. It will be readily understood that there are few Chiropractors whose training has been sufficient to enable them successfully to accomplish such research. There are thus many things connected with the spino-organic connections which are commonly held as facts but which should be classed as presumptions. And the prevalence of the habit of general adjustment rather than specific makes the future final solution of all these problems remote.

Kinds of Evidence Acceptable

It will be seen that of the three kinds of evidence--Anatomical, Physiological, and Clinical--which are admissible in reasoning upon the connection between the spine and disease, only one form--clinical evidence--has been adduced by Chiropractic. For anatomical and physiological corroboration of our apparent clinical findings we are obliged to turn to standard works on these subjects; fortunately we find it in abundance.

Anatomy, fortified now by research in the morphologic relations of the parts studied and by physiological and pathological experiment which has thrown much light on the proper viewpoints from which to describe structure, contains sufficient data on the nervous system to enable us to explain practically every fact observable in a Chiropractic clinic.

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.

In the main these nerves of motion and sensation are arranged as follows:

The Cervical plexus is composed of the intertwining of axons from the anterior primary divisions of the four upper Cervical nerves. Its branches pass to and innervate many voluntary muscles of the neck and side and back of head, and supply sensor fibres to the adjacent cutaneous areas. Branches also communicate with the last three cranial nerves and one long branch, the Phrenic, or Internal Respiratory Nerve of Bell, passes through the neck and thorax to the diaphragm, as its motor nerve.

The Brachial plexus is made up of the anterior primary divisions of the four lower Cervical nerves and the greater part of the first Thoracic. It is distributed chiefly to the voluntary muscles and integument of the shoulder and arm, forearm, and hand, but sends branches to some muscles of the neck and upper back as well. It, like the Cervical plexus, receives branches from, but gives none to, the Cervical sympathetic.

The Thoracic nerves are not arranged in plexiform fashion like those above but pass separately, for the most part, to their destinations. They are distributed to the walls of the thorax and abdomen following the curve of the ribs in direction. The last Thoracic sends one division downward as far as the outer aspect of the ilium.

The Lumbar, Sacral, and Pudendal plexuses are formed of the ventral divisions of the Lumbar, Sacral, and Coccygeal nerves and distribute branches to the integument and voluntary muscles of the lower abdomen, pelvis, and lower extremities. From two of the sacral nerves branches known as “Visceral” pass through the plexus to terminate in the walls of the uterus and rectum.

All of the thoracic nerves and the first and second, sometimes the third and fourth, lumbar give off branches to the sympathetic ganglia, known as white rami communicantes.

Direct Distribution of Cranial Nerves

The distribution of the 12 pairs of cranial nerves is not so definitely to voluntary muscles and to areas from which conscious sensation is to be derived as is the case with the spinal, although the cranial nerves present many analogies with the spinal and there is abundant reason for considering them as in one series of 43 pairs. There is direct distribution of some cranial nerve fibres to secreting glands, but these fibres are probably merely derived from sympathetic trunks and carried in company with the axons of cranial origin. There is also some direct distribution of cranial nerve axons to visceral walls made of non-striated muscle, as in the case of the vagus distribution to the respiratory and alimentary tracts and that of the spinal accessory to the heart. This is a resemblance to the sympathetic.

The cranial nerves carry afferent impressions from the special sense organs, except those of the sense of touch, which function is divided with the spinal nerves.

Various intercommunications exist between the cranial and sympathetic divisions of the peripheral system, by means of which axons starting with one division may be finally distributed with another, or by which an axon of the sympathetic may pass to one of the sensor ganglia of the cranial system and influence its nutrition and condition, and therefore its power to act. There is a limited intermingling of spinal fibres with the lower cranial.

Distribution of Sympathetic

The sympathetic system directly innervates most of the nutritive or vegetative system, the alimentary tract and its accessory organs, the vascular systems, the genito-urinary system, and the ductless glands. To a limited degree it shares this control with the cerebro-spinal and to a much greater degree it brings the central axis into indirect connection with these viscera.

Gray says, “The distinction of the sympathetic system from the cerebrospinal system is made merely for reasons of convenience. The two systems are intimately connected and the sympathetic is morphologically a derivative of the central axis disseminated in connection with the nutritive apparatus and establishing relationships among the vegetative organs.”

Structure of Nerve Pathways

Most pathways which carry nerve impulses from their origin or inception to the organ in which they are finally expressed as action of some sort or translated into sensation or into stimuli which pass out reflexly over a connected neuron, are composed of more than one neuron. The neurons of a nerve pathway are arranged end to end with the axons all pointing in one general direction so that the nerve energy travels always in the same direction over the entire nerve path. Impulses are transferred from the first neuron in the chain to the second, and from second to third, etc., by contact of the telodendria of the one neuron with the dendrites or receptive processes of the next. Part of the nerve pathway may be within the central axis and part within the trunk of a peripheral nerve.

Several peripheral pathways for afferent impulses may be joined to an efferent pathway so as to complete reflex arcs and the efferent cell be under the controlling influence of some upper neuron coming down from the central axis with the power either to permit or to inhibit the reflex acts which would otherwise take place as a result of peripheral stimuli. Several such lower cells may be under the domination of one upper neuron.

In some instances the nutrition of ganglia or nerve trunks, or of parts of the central axis itself, is under the control of sympathetic neurons terminating in connection therewith, so that interruption of the normal action of the sympathetic neuron may be followed by effects manifested through some distant part of the cerebrospinal system. In the following pages we shall discuss nerve pathways with reference to the explanation of diseases caused by vertebral subluxation impinging nerves either by tension or constriction, and therefore our grouping of parts will differ somewhat from any anatomical or physiological grouping with another object in view.

Important Nerve Pathways

_To brain_: C 2, 3, or 4 to superior cervical ganglion by direct impingement, through internal carotid nerve to sympathetic plexuses following branch arteries from Circle of Willis. The blood-supply of the brain is under control of the cervical sympathetic and most brain lesions or diseases are due to vascular changes leading to anaemia, hyperaemia, inflammation, or hemorrhage.

_To meninges_: Loop between first and second cervical nerves to trunk ganglion of vagus and through meningeal branches of vagus (P), or by way of internal carotid nerve to pial sympathetic plexuses. (P) The connection of the first, second, or third cervical with cerebral meningitis is established clinically but there is still doubt as to the explanation.

_Eye and Muscles_, _Retina_, _Optic Nerve_: The external muscles of the eye, the four recti and two oblique with the levator palpebrae superioris, are innervated by the Oculomotor, or third cranial, and the fourth and sixth cranial, which receive branches from the cavernous plexus of the sympathetic derived from the internal carotid branch of the superior cervical ganglion. As the ganglion lies in front of the transverse processes of the second, third, and fourth cervical vertebrae, direct impingement upon it by subluxation of one of these vertebrae may cause strabismus or other affection of the external ocular muscles.

The eye-ball receives filaments from the ciliary or ophthalmic ganglion, which in turn is connected with the cervical ganglion by way of cavernous plexus and internal carotid nerve. This pathway controls the radial fibres of the iris and dilates the pupil as a part of the light accommodation reflex mechanism. Loss of pupillary reaction, especially with small pupils, suggests upper cervical subluxation.

The retina, containing the cells of origin of the optic nerve axons and being the special end-organ of the sense of sight has no direct spinal or sympathetic connections but its blood-supply, and therefore its nutrition, is influenced by branches from the sympathetic which enter with the central artery of the retina. Retinal hemorrhage has been cured by cervical adjustment, C 2, 3, or 4.

The conjunctiva is innervated by the sympathetic and by the fifth cranial, or trigeminal.

_Olfactory Nerve_: Nerve of smell, distributed to the Schneiderian membrane over the upper portion of the nasal septum and over the upper lateral wall. There is no known connection by which the trunk of the olfactory nerve can be reached by adjustment but the condition of the special end organs in the membrane and their ability to functionate depend not only upon the integrity of their axons but also upon the nutrition and moisture of the membrane in which they are embedded. This is under the control of the Vidian nerve and of branches from the spheno-palatine, or Meckel’s ganglion, both connected with the carotid plexus of the sympathetic and therefore responsive to adjustment of C 2, 3, or 4. This is also the route by which epistaxis is usually checked.

The external nasal muscles, like those of the rest of the face except some of the muscles of mastication, get their supply from the facial nerve, which connects with the sympathetic plexus on the middle meningeal artery. It may be said parenthetically here that peripheral facial paralysis (Bell’s palsy) yields to adjustment and proves the value of this connection. The nasal integument is under the sensor control of the trigeminal and trophic disturbances may result from its involvement.

_Trigeminal Nerve_: This is the great sensor nerve of the face and carries a motor division, the inferior maxillary, to some of the muscles of mastication, as the temporal, masseter, and buccinator. It has connected with it four ganglia, which also receive sympathetic roots, and the ganglion of origin of its sensor axons, the Gasserian or semilunar, also receives direct sympathetic communications. The importance of this communication is shown by the powerful effect of adjustment of third or fourth Cervical for tic dolouroux.