Chapter III: Introduction (2)

It should be remembered that with the first two Dorsals the transverse will be found in a transverse plane which would pass between its own spinous process and that above. This is also true of the last three Dorsals, while in the middle Dorsals the transverse is usually (not always) level with the tip of the spinous process of the next superior vertebra.

Before adjusting, to determine the _location_ of a transverse process in order to direct an adjustment against it, first palpate spinous process and hold it with the tip of the middle finger. Then approximate with the first finger a point even with the tip of the spinous process above and about one inch from the spine--this of course in mid-dorsal. Then let second and third fingers follow the first so that all three rest on or near the transverse to be palpated. Pressing gently, but firmly, move the three fingers until the process can be felt beneath them. Hold the process with the middle finger so as to direct with it the contact of the adjusting hand to a point exactly over the transverse process.

Lumbars

The transverses of a Lumbar vertebra lie just even with the interspace between their own and the adjacent superior spinous process. They are deeply embedded in muscle tissue and very hard to palpate. They may vary considerably in size or length and the last one or two may be absolutely impalpable. It is sometimes advisable to adjust a rotated Lumbar by using the transverse as a lever, but this should never be attempted unless the process can be distinctly felt. The method of locating in Lumbar is practically the same as in the Dorsal region.

Transverse Palpation with Patient Sitting

Palpation of Cervical transverses in position A has been described and is frequently done. Palpation of Dorsal or Lumbar transverses in the same position may sometimes be desirable. It can be done with the same movement as spinous process palpation, and may serve to detect a bent spinous process.

If it is necessary to palpate both transverses at the same time, stand in front of the patient and lean over his shoulder, letting his shoulders rest against your body. Use palmar surface of fingers of both hands and note which transverse is posterior to its fellow, if either, or whether both are posterior to the line of the others above and below them.

It is rarely possible to find if a transverse process be superior or inferior to its normal position, except the Atlas transverses, although this may occasionally be detected. Fortunately this is a rare form of subluxation, or appears rare, although it must be said that this apparent rarity may be due to our comparative inability to detect it in the living subject.

CURVES AND CURVATURES

For convenience, _curve_ is used to denote the normal curvilinear deviation from a straight line naturally present in the normal spine or naturally assumed in response to the need for equilibrium during the erect position of the body: _Curvature_ means either the abnormal increase of any normal curve or the appearance of any abnormal curvilinear deviation of vertebrae from their normal position. Deviations from normal must contain at least three vertebrae to be considered curvatures.

Visual Examination

The general inspection of the spine which precedes the count should bring to light, in addition to prominent subluxations, and general symptoms observable by inspection of the back, any _marked curvatures_. Their general locality and direction will be noted by this observation and their details left to be discovered by closer examination.

During palpation with a long and rapid glide one may also note these general points with respect to any curvature.

Do not mistake the four normal curves, the anterior Cervical and Lumbar and the posterior Dorsal and Sacral, for curvatures. The normal Lumbar curve is so unusual in practice that a novice has been known to name it a lordosis.

Description of Curvatures

Four varieties of curvature are commonly described. _Kyphosis_ is a curvature with its convexity directed backward, usually, but not always, found in the Dorsal region. _Lordosis_, the opposite of Kyphosis, is an anterior curvature, usually in the Lumbar in which case it is an accentuation of the normal curve. _Scoliosis_ has its convexity directed laterally either to the right or the left. It is commonly also _Rotatory_, having its vertebrae rotated around their vertical axes so as to make the outer or the inner transverses more prominent than those on the other side.

In a Scoliosis the rotation may swing either the bodies or the spinous processes toward the convex side of the curvature; the latter is much the easier of adjustment while the former furnishes one of the most intricate problems of adjustment.

Cause of Curvatures

Without entering here into a discussion of those disturbed metabolic processes--themselves the result of subluxation--which result in curvature by general softening of the bone, as in rachitis or spondylitis deformans, we will simply state the general proposition that almost all curvatures which are in any degree _angular_ result from a single subluxation to be found at the point of the angle. It has been demonstrated in such cases that adjustment at that point will correct the curvature in time but it is usually wiser to hasten matters by selecting other points of attack by a method to be presently suggested.

Long, regular, but not pronounced, Scoliosis, usually in the Dorsal, may be an example of _occupation curvature_, following the continued use of muscles in a fixed position and not due to subluxation. Another example is the mailman’s Lordosis. These in themselves are not detrimental to health and are negligible unless some special point of impingement through individual subluxation exists within them.

The sharp, angular kyphosis of Pott’s Disease, tubercular caries of the vertebrae, the curvature involving three or four vertebrae which are extremely tender to palpation, should warn against adjustment unless one can be very certain that the vertebrae are sufficiently intact. Fracture of a decayed vertebra is easily possible under adjustment. The cause of Pott’s Disease is usually at the angle point, most frequently the tenth Dorsal but possibly any Dorsal from fifth to twelfth.

Record on Curvatures

If it is the purpose of the examiner to straighten the curvature he should choose for adjustment a series of non-adjacent vertebrae which are most prominent in the direction of the curvature; thus in a right scoliosis he should choose only those vertebrae most prominently out to the _right_, and in a kyphosis only posterior ones. A lordosis as such cannot be properly adjusted except in the Cervicals, but lordosis is usually a compensating curvature (see below) and can be otherwise corrected.

If the patient suffers from some disease which assumes more importance than the curvature and demands attention, select the one vertebra which is causing the disease, without reference to its position in the curvature, and adjust that vertebra into a proper relation with the adjacent ones, even though you adjust directly toward the convexity of the curvature. Disease may often be relieved by _making a curvature regular_ more quickly than by eliminating the entire curvature. Sometimes both considerations may influence the selection of vertebrae.

In a curvature there is not necessarily pressure on nerves at every foramen. In fact, such pressure is the exception rather than the rule in curvature and a careful study of the spine must be made in order that adjustments may be accomplished without _causing_ temporary impingement here and there.

A foot-note describing curvature may be appended to the record of palpation. It should contain the special name of the curvature, whether simple or compound, and the numbers of the first and last vertebrae in it. For instance, note may read: “Right rotary scoliosis from D 3 to L 1 inclusive.”

Compensatory Curvatures

When a primary curvature is present one or two secondary curvatures usually appear to preserve the equilibrium of the body. With a Dorsal kyphosis there is often a Lumbar lordosis and sometimes less marked lordosis in both Cervical and Lumbar. With a primary right scoliosis in the Lumbar there will be a secondary left scoliosis above. The secondary curvature is called compensatory. In selecting vertebrae for adjustment it is well to neglect the compensatory curvature as much as possible, leaving it to right itself as the primary one is corrected. If, however, the primary curvature be a lordosis, and not adjustable, work on the secondary curvature may gradually aid in reducing the primary, to a certain extent at least.

Ankylosis

This topic is discussed here partly because it is so often associated with curvature.

Ankylosis can be appreciated only by detecting the lack of normal movement between adjacent vertebrae. Place a finger in the interspace between suspected vertebrae and ask the patient to perform the movement calculated to separate the spinous processes in a normally movable spine. If in the Dorsals, ask him to drop the head and shoulders as far forward as possible without bending at the hips. Alternate repetitions of this movement with straightening and the spinous processes should alternately separate and approach each other. Test several successive vertebrae so as to note that all change their position except two.

In the Lumbars have the patient repeatedly bend the body forward from the hips striving to make his spine convex backward. In the Cervicals forward flexion of the head will serve. Occasionally general ankylosis is found with curvature, as in Spondylitis Deformans.

Many Chiropractors mistake failure to move a vertebra with an attempted adjustment for evidence of ankylosis. In nine cases out of ten such failure is due to other reasons, ankylosis being very infrequent. It is a much abused excuse for incapability. Free movement between spinous processes is _absolute proof_ that the vertebrae are not ankylosed.

DIFFICULTIES IN PALPATION

The chief difficulty arises from failure to observe some of the rules herein laid down.

Carelessness or inattention precludes accuracy.

Pain may cause the patient to assume an unnatural or cramped attitude simulating curvature, especially of the Cervicals. More errors occur from this cause in judging the laterality of C 2 than with any other vertebra.

The occasional bent spinous process in Cervical or Dorsal regions may deceive the palpater unless transverse palpation is employed. But the frequency of slightly bent processes in dry spines and a superficiality of reasoning upon the subject have led to great overestimation of their importance. As a matter of fact only a very few maladjustments arise from deception of the palpater in this way, though the profession contains few practitioners who make a routine method of verifying by the transverses. The reason is simple. Bent processes are caused by direct violence applied before the union of shaft and epiphysis is complete. Sufficient force to produce a change of direction usually produces subluxation _in the same direction_. Adjustment continued until the offending process was quite aligned with its fellows would constitute overadjustment, but adjustment is not usually continued after all symptoms have subsided, so that actually small harm occurs through failure to detect bending.

An epiphyseal plate may be absent, having been broken off by trauma and absorbed. This can be discovered by noting the too-wide space between apparently adjacent vertebrae, and careful palpation will disclose the apparently much anterior vertebra, an appearance not borne out by the position of the transverses. When an epiphysis is absent a patient has a somewhat weak back from lack of muscular attachment.

Lipoma, or the heavy cicatrix following a burn or carbuncle, may render palpation of two or three vertebrae impossible. In such a case only the palpater’s experience and his knowledge of the characteristics of various vertebrae will enable him accurately to number the remainder.

Patients with much adipose tissue may require palpating in several positions in order to permit certainty.

A deep third Cervical which is absolutely impalpable may mislead one, but a careful count which shows one vertebra overlooked indicates the necessity for a careful re-examination of the Cervicals, by which the gap at the third at least may be appreciated. If the Axis is very much inferior the third is especially likely to be overlooked.

Anomalous cases have been found in which there were more or less than the usual number of movable vertebrae, the usual deviation being the presence of twenty-five, and the extra one being most commonly a Lumbar. In one case under my observation there were twenty-five movable vertebrae, apparently thirteen Dorsals according to shape, and only eleven pairs of ribs posteriorly, two pairs being dichotomous so that there appeared thirteen pairs anteriorly. Deviations in number occur, in my experience, about once in five hundred cases.

LANDMARKS

The regional location of vertebrae by means of certain landmarks (so called) in or near the spine, is a much discussed question in the profession. Without discussing the various arguments in favor of this method, chief of which is the _inability of the untrained to count vertebrae_, let us set forth the principal landmarks used and the facts in regard to them.

The seventh Cervical, called Vertebra Prominens, is usually considered a guide to the count. In over three hundred cases examined for that purpose the seventh Cervical was found to be Vertebra Prominens in about 65%, the other 35% showing the sixth Cervical or first Dorsal to be the prominent one. This method is two-thirds as accurate as counting.

The tubercle (Chassaignac’s) of the sixth Cervical transverse is said to be directly opposite the lower border of the cricoid cartilage and this is a better guide than the above.

The third Dorsal spinous process is said to be on a level with the root of the spine of the scapula, and with arms hanging at sides, the upper angle of the scapula to be on a line between first and second Dorsal spinous process. This is not at all constant.

The inferior angle of the scapula is said by some writers to be on a line with the tip of the seventh Dorsal spine. Others locate it opposite the interspace between seventh and eighth Dorsals. Still others give it as opposite the eighth Dorsal spine. All are correct--_sometimes_. In truth, the inferior angle may be opposite any part of the spine between the sixth and ninth Dorsals. There is nothing constant about it.

The twelfth rib may be followed to its articulation with the twelfth Dorsal vertebra. This is a good guide, providing that the rib can be palpated. The lower margin of the last rib is usually even with the spinous process of D 12 about one inch and a half from the mid-spinal line. The humor lies in the fact that the patient upon whom the count is so difficult as to require this verification is usually obese and obesity renders the rib impalpable.

The line drawn between the iliac crests falls between the third and fourth Lumbar spinous processes in about 98% of all cases. _This is our most reliable landmark._ It is used as described under the Count.

All landmarks except the last two show such variance in different individuals as to be quite unreliable. The correct method of numbering spinous processes is the obvious and logical method--_count them_. The skill and accuracy of touch required for successful counting is invaluable in determining direction of subluxations.

MENTAL ATTITUDE

In order to secure that absolute concentration without which it is impossible to appreciate properly those tactile impressions for the very _reception_ of which such continued practice is necessary, the hands should leave the spine as little as possible during palpation; a second person should record subluxations found so that the palpater need only state, and not write, his conclusions; light pressure on the spine should always be used, as a heavy pressure desensitizes nerve-endings in the fingers; and silence should be maintained except for the necessary statement of points to be recorded.

Palpate as rapidly as is consistent with good work. The more rapid the palpation, _if concentration is absolute_, the more accurate the impressions received.

The _end_ and _aim_ of palpation is to determine the means by which impingement of nerves may be removed with the greatest rapidity and success. Palpation includes such a study of the vertebral column as will fix in your mind a clear thought-picture of the impinged nerves throughout its length.

FINALLY

If you would achieve success in Vertebral Palpation, be persistent. Spare no labor to acquire that accuracy of detail which distinguishes the expert from the amateur. You can make of yourself what you will. There is no limit to the ability which may be acquired. Another may guide your hands but with _you_ lies your success.

NERVE-TRACING

Definition

Nerve-tracing is that branch of palpation by which the tenderness of irritated spinal nerves is discovered and their paths demonstrated.

Organ-Tracing

Organ-tracing is that branch of palpation which deals with the outlining of the boundaries and surface markings of a tender organ or part.

Palpaters frequently confuse tenderness of one of the parenchymatous viscera for the tenderness of interlaced and branching nerve filaments, especially in the abdominal region. The fact that the tender area takes on the characteristic shape of one of the viscera is conclusive evidence that an organ, and not nerves, have been traced.

What Nerves Traceable

Any spinal nerve may be traceable for at least a part of its course. The cranial nerves are made inaccessible to palpation by their location, except the spinal portion of the spinal accessory and the terminal portions of the nerves to the face. Likewise the sympathetic trunks, except perhaps in the neck, are untraceable.

Nerve-tracing is comparatively easy in the upper and lower extremities, neck and back. The superficial nerves of the scalp are hard to follow on account of the hair. The superficial nerves of thorax, abdomen, and pelvis are accessible under the conditions mentioned below; the deep or visceral branches, never.

Of those nerves mentioned as traceable, only such as are _irritated_ and consequently swollen and tender, can be followed. If a nerve is very heavily impinged, especially if the impingement be chronic, it is partially or wholly paralyzed and not traceable. If the heavy impingement be acute, or if there be a light impingement serving as a mechanical irritant, nerve-tracing is a real aid to diagnosis.

Proportion of Cases with Traceable Nerves

About one-half of all the cases which visit Chiropractors for adjustment are susceptible of nerve-tracing. In the remaining half it is absolutely impossible to acquire any information in this way. Of the half who are at all susceptible, it is possible in perhaps four-fifths of all cases to secure _some_ accurate or reliable information.

The patient in whom all accessible nerves seem tender to light palpation is hyperesthetic and unavailable for tracing.

In the usual case one or two nerves will be found easily traceable, while the rest exhibit no tenderness on pressure. Such a case furnishes the most reliable information securable by this method and the tender nerves may be considered as lightly or acutely impinged.

Preconception of Nerves Essential

Knowledge of the anatomy of the nervous system is a part of the necessary equipment of the Chiropractor who would trace nerves and this knowledge should be so thorough as to enable the palpater to recognize each tender line found as an anatomically described nerve-path or an error on his part. The examiner must know the paths of all nerves and be able to predict from the first tender points discovered the probable course which the tenderness will follow, so as to direct his search along that probable path.

He must be able to detect unconscious deception on the part of the patient through his knowledge of the anatomical impossibility of the apparent tracing. For instance, if for any reason he may appear to have traced a nerve upward beside the spinal column from D 10 to the eye by way of the vertex, he must know that this is an illusion--because such nerves do not exist and cannot be anatomically demonstrated--or accept the well merited ridicule of any educated person who discovers his absurdity.

Because of the difficulty of determining whether the tender structure found be muscle, nerve, or viscus, and because of the natural suggestibility of both palpater and patient, nerve-tracing cannot be so reliable a guide to nerve-paths as is dissection. It should not be necessary to state this obvious truth but the calm acceptance, by many, of the weird conclusions based upon a belief in the infallibility of nerve-tracing testifies that it is necessary.

Nerve-tracing is valuable only where the nerve-path outlined as being tender corresponds to the known path of some nerve.

Suggestion

Paradoxically, knowledge of nerve-paths may lead to error. By the law of expectancy, we are prone to find what we look for and if we hold too strongly to the belief that because we have found one or two points of tenderness we must find a series of points extending along a mentally pictured nerve-path, we may search until we falsely believe that we have found this series.

Likewise the patient, having been carefully informed as to the manner of procedure and knowing what we expect to discover, may unconsciously deceive us by feeling tenderness in response to suggestion, where no real impingement exists.

Place in Diagnosis

The value of nerve-tracing in diagnosis has been much overestimated by many, though the tendency of the profession seems to be toward rationalism along that line.

Whereas, in palpation of the spine every real subluxation gives evidence of disease, or tendency to disease, while every normally aligned pair of vertebrae furnish proof that no disease can exist in the area of distribution of the nerve emerging between them, nerve-tracing is much less reliable. If the tender nerve be traceable to a vertebral subluxation it may be taken as additional evidence that the effect of that subluxation is _disease_, rather than _tendency_ to disease, truly an important distinction, but scarcely broad enough to support a diagnosis without aid.

The absence of tenderness from nerves does not negative a disease in any instance, whereas the absence of subluxation _does_. Like all other expedients for the selection of vertebrae for adjustment without admitting the necessity for first acquiring much skill by much labor, nerve-tracing has a great weakness. Only irritated nerves are tender and the effects of subluxation may be either irritation or paralysis.

If accurately done, sources of error carefully eliminated, and the results of nerve-tracing found to correspond with the condition of the spine and the other symptoms, this method of demonstrating to the patient the connection between the vertebrae and the diseased region of his body is valuable. It aids in convincing him of the validity of the Chiropractic theory.

TECHNIC OF NERVE TRACING

Where to Begin

The palpater, having made his vertebral palpation, may begin at some point in the body indicated by the symptoms as diseased and, finding tenderness, follow the path of a nerve back to the spinal column where the nerve may be fairly presumed to enter the intervertebral foramen.

Or he may use his palpation record as a guide and follow the tender nerves outward to their periphery. This is the better method.

Palpation as Guide

When palpation has been made, remember that the impinged nerve is usually found on the side opposite to the direction of the spinous process in its departure from the median line. With a left subluxation the tenderness is usually, though not always, on the right side. If in the Lumbar, and the subluxation a rotation, the impinged nerve will be found _below_ the transverse process of the subluxated vertebra. In the Cervical and Dorsal regions the tender nerve is usually below, but may be either above or below, the transverse of the subluxated one.

Examine the nerves having exit from the foramina of each subluxated vertebra in turn from above downward. When a tender point is found about an inch from the mid-spinal line, attempt to follow the nerve and palpate until it has been traced as completely as possible.

Where to Expect Tenderness

The region immediately surrounding the spinous process of the subluxated vertebra may be tender because of impingement of the axons of the posterior primary division of that spinal nerve which emerges below the vertebra. Such tenderness is more common with anterior subluxations than with others. It is not to be confused with the _soreness_ which often appears after adjustment and is due to bruising or straining of the tissues.

Nerve tenderness may be discovered at a little distance from the mid-spinal line and at a level slightly lower than the emergence of the nerve. If a nerve is irritated, the finger inserted between the ribs near their articulation with the transverse processes will elicit tenderness. The discovery of tender points along the spine is the most important part of nerve-tracing.

Nerve-Paths

Detailed description of the paths of all the spinal nerves may be studied from any standard work on anatomy and will not be included here, but it may be well to remind the reader of certain general tendencies.

The spinal nerves do not cross the median line in front except perhaps fine interlacing fibres.

In the Dorsal region the nerves are usually found following the interspaces until the lower ones debauch upon the abdominal wall anteriorly. There are, however, some Dorsal and lower Cervical nerve bundles which pass obliquely downward and outward to innervate back muscles.

Reference to the section on Spino-Organic Connection will make clear the tissues supplied by each nerve.

_Slight_ deviations from the usual course of nerves are common; _marked_ deviations very infrequent.

Use of Fingers

Use second finger of either hand for the palpating finger, choosing the hand which can be most conveniently used as determined by the position of patient and the part of the body to be examined. There is no set rule. Reinforce this second finger by the pressure upon it of the first and third and, if desired, by pressing thumb against it. (See Fig. 5.)

Apply the tip of the palpating finger to the nerve with a motion such that it crosses the path of the nerve at right angles back and forth. Meanwhile the probable path of the nerve must be kept in mind. As the finger crosses the nerve-path it makes steady and even pressure upon any structures passing beneath it. The motion of the hand is almost a rolling motion, the finger tip probing, as it were, for a tender spot.

Tenderness--How Recognized

The irritated condition of the nerve which has thus been rolled beneath the finger may be recognized in one of three ways; the patient may involuntarily flinch, betraying the hurt; or he may inform the palpater of the hurt; or the swollen, cord-like nerve may be felt.

The two former are the reliable guides, while the latter is only occasionally possible. In children and in feeble-minded, insane, or mute adults, the first mentioned method must be relied upon entirely. Muscular contraction is the unconscious or reflex response to pain and often occurs independently of the intelligence or state of mind of the subject.

Of all the three methods the one most commonly relied upon is the second--the statements of the patient.

Instruction to Patient

The patient should be informed of your intentions when palpation is begun and should be asked to answer every time you apply your finger, saying, “Yes,” if the spot is tender and, “No,” if not. He should speak promptly each time so as to avoid self-deception which might come with reasoning upon his sensations. Occasionally vary the steady rhythm of your movements by omitting one and note if the patient responds mechanically when you do not press.

At times during the tracing, it is well to depart from the probable nerve-path and to touch again a point marked as tender, to see if the patient’s information may be relied upon. Whenever you leave the nerve-path his answer should be, “No,” immediately changing to, “Yes,” when you re-cross the tender line.

Marking Tender Points

At each tender point noted a small mark should be made with an eye-brow pencil or other grease-paint, which leaves a distinct but easily removable mark. These tender points should be noted and marked at intervals of about an inch.

Connecting Line

When the entire nerve-path has been traversed in this way, draw a line with the eye-brow pencil, passing through all the marks indicating points of tenderness. This line should be a sufficiently accurate rough outline of the nerve-path to make clear the spinal connection with the diseased area. The significance of this connection will be better understood when the section on Spino-Organic Connection has been studied.

Common Findings

In muscular rheumatism, neuralgia, neuritis, or in case of a local boil or abscess indicating local disturbance of the trophic influence of nerves, clear and definite tracings are common. Muscular spasm, such as wry-neck, usually has a very tender nerve associated. Localized painful disease of any kind is likely to be associated with a very definite nerve tenderness, as is the case frequently with appendicitis, ovaritis, hepatic colic, etc.

The painless disorders, or various disorders of spleen, diaphragm, heart, lungs, etc., though they be of a very serious nature, seldom are discoverable by nerve-tracing unless their serous membranes are involved. Tracings _may_ be made from D 2 or 3 to anterior thoracic walls in heart or lung disease but are not common.

Any spinal nerve may be traceable at times through at least a part of its course.

Sources of Error

Several of these have been mentioned, such as the natural suggestibility of both examiner and patient. Among others are: failure in the back, thigh, or leg to reach the really tender nerve because of the interposition of several muscle layers between it and the finger, ignorance of nerve-paths, failure to apply equal pressure to all parts of a nerve, application of such heavy pressure that muscle tissue is bruised and hurt, and failure of full co-operation on the part of the patient. Let us consider these in turn.

If several muscle layers interpose themselves between the searching finger and the nerve, it is proper to push aside the intervening layers, using a twisting and rolling movement until the finger feels _underneath_ the muscles. This done, and a tender nerve found underneath several muscle layers, the same amount of overlying tissue must be pushed aside each time the finger searches for the nerve. Only exhaustive study of the anatomy of the typical nervous system will enable the examiner to know exactly at what point a nerve will become more or less superficial. Unless he does know this it is best to follow the neutral rule that nerves tend to follow the long axes of ribs and limbs and to maintain their depth beneath the surface throughout their course. This statement is too general for accuracy.

Care should be taken that equal pressure be made on all points palpated on one nerve. If the nerve pass over a bone, _less force_ is needed to exert the same pressure than if it overlie muscle or other soft structure. The force used varies constantly as the hand moves from place to place, according to the density and hardness of the structures overlying and underlying a nerve.

Sufficiently heavy pressure will elicit tenderness in all except anaesthetic patients. But if a nerve be irritated it will be tender without heavy pressure, when the finger really makes a close contact with it.

If the patient willfully attempts to deceive the palpater, nerve-tracing might as well be abandoned except in those extreme cases where the patient will flinch against his will on account of extreme sensitiveness.

Use of Second Hand

As far as possible, the second hand is placed opposite the tracing hand and steadily supports the body; its position changes with changes in the position of the first. If the arm is to be examined it had best be held away from the body, and the part to be examined held between the two hands.

Position of Patient

For tracing nerves in the neck, back, and upper extremities, the patient should sit easily. For lumbar, abdominal, or pelvic tracing, or for tracing in the lower extremities, have patient lie on side or back. Do not hesitate to change the position of the patient as often as is necessary to secure easy access to the part to be examined and relaxation of the patient’s muscles. Never allow the assumption of a strained position during tracing; the sensation of cramped muscles may be confused with sensations of nerve tenderness.

SUBLUXATIONS

Definition

A vertebral subluxation is a displacement, less than a dislocation, in which the chief element is the partial loss of normal apposition of the articular surfaces of the subluxated vertebra with those of the vertebra above or below, or both. Or, Vertebral subluxation is a permanent partial dislocation.

How Produced

Subluxations are primarily caused by trauma--falls, blows, strains, etc., being the chief factors. Hereditary weakness in structure of some part predisposes by rendering that portion more easily displaced.

Subluxations are never hereditary but may be congenital through violent or instrumental delivery into the world or may _appear_ hereditary because they occur shortly after birth through the effect of light jars upon the hereditarily weakened segments of the spinal column.

They are always the result of concussions of forces; never of forces acting entirely _within_ the organism. They result from the contact of the body with its environment.

It has been said that muscular action in response to peripheral irritation may produce subluxation. The laws of reflex action render this impossible. Given a normally aligned vertebra, and consequently normal nerves and a normal reflex arc in that segment, the ventral horn cells respond to a _slight_ peripheral stimulus by exciting muscular contraction on the _same_ side with the irritation. If the irritation be sufficiently increased, the response occurs on _both_ sides but most strongly on the side from which the irritation comes. Greater irritation merely serves to cause greater distribution of the responsive action. (See any standard physiology on reflex action.) In no case will the difference between the contractions of muscles on the two sides be sufficient to displace a normally aligned vertebra. Nature has provided against that contingency.

Given a subluxated vertebra causing nerve impingement and thus interruption of the normal action of the reflex arc, irritation may result in greater contraction upon the _opposite_ side than upon the side of the irritation. This is an abnormal condition and accounts for the _increase_ of previously existing subluxations under pain or peripheral irritation. But in every instance trauma must and does precede and cause subluxation.

Reaction of Secondary Causes

Once produced, however, a subluxation may not cause noticeable effect until it has been _increased_ in degree by the reaction of forces within the body such as poisons, general fever, etc. Thus germs, dietetic errors, exposure to sudden temperature changes, waste of energy through abnormal mental activities, as hate, fear, worry, etc., or through physical excess--in fact, all the _secondary_ causes of disease may _appear_ to have produced a subluxation. In fact, they have merely accentuated that which already existed and have done so through the muscular contractions which they induced.

General thinning of intervertebral substance through a condition of disturbed metabolism itself produced through the agency of some _one_ serious subluxation, may narrow all the foramina and increase impingement of nerves at any point where a slight subluxation previously existed. An irritated nerve may become swollen and the nerve impinged at the foramen.

Law Governing Location

So definite is the law governing the effect of force applied to a given portion of the body upon an associated vertebral segment that the skilled Chiropractor who has studied vertebrate segmentation thoroughly may determine, from the history of a fall or injury, the vertebra which would tend to be subluxated by that injury and the tissues controlled from that part. The rule is this:

_Force applied to any body segment tends to subluxate the segmentally associated vertebra. This subluxation tends to produce disease throughout the area of distribution of the subjacent pair of spinal nerves._

The task of explaining this law seems hopeless unless the student is familiar with human embryology and the life history of the vertebrata, as well all the details of human anatomy. To such a student the law will be self-evident, so interwoven with the threads of higher organization as practically to form its pattern.

In simple terms we might offer this general statement. Any force applied to the body with sufficient violence will produce subluxation of the vertebra above the spinal nerves supplying the injured area. Thus, the brachial plexus controls the arm and shoulder and connects with the spine by way of the 5, 6, 7, 8, Cervical and 1 Dorsal nerves. Any force striking the arm or shoulder tends to produce subluxation of the sixth or seventh Cervical or first Dorsal vertebra so that all permanent disease conditions resulting will be found in the arm or shoulder or nearby tissues of the neck.

This theme presents a magnificent field for individual study and research but is, per se, beyond the limitations set for this work.

Effect of Subluxations

Slight subluxations may exist, because of the adaptation of surrounding parts and the slight play within the intervertebral foramen, without producing noticeable effect. They always, however, evidence a _tendency_ to disease.

The majority of subluxations do produce disease, to some degree, and do so by _impinging nerves_. Impingement may be either by pressure _against_ a nerve or ganglion or by _constriction_ of a nerve where it passes through an intervertebral foramen; the former occurs in the case of the Cervical sympathetic, the sub-occipital nerves, and the sacral nerves; the latter is the commoner form in Dorsal and Lumbar regions of the spine. Probably the most positive constriction of a nerve which can occur within the body is to be found in rotation of Lumbar vertebrae; the body of the rotated vertebra encroaches upon the inferior nerve on the side opposite to the direction taken by the spinous process.

Either variety of impingement produces disease, morbid structure or function, by irritation of the nerve: light impingement irritates, heavy impingement partially or completely paralyzes, the nerve.

VARIETIES OF SUBLUXATION

According to the abnormal relations between vertebrae subluxations may be variously described as rotated, tipped, anteriorly, posteriorly, or laterally displaced. They commonly combine two or more of these forms, so that the purely rotary or the entirely lateral subluxation is uncommon.

Rotation

Every vertebra has a vertical axis around which it tends to rotate. This axis is not always the center of mass but depends upon the arrangement of mass, the fixity of cartilages, ligaments, and muscles, which tend to hold some parts of the vertebra more fixed than others, and the apposition of articular processes, which tends to prevent movement in certain directions.

The axis of rotation of the first Cervical is the center of the odontoid process of the second Cervical, which articulates with the transverse ligament and anterior arch of the first. A frequent subluxation of the Atlas is a rotation around this process so that the one transverse is permanently posterior to its normal position and the other correspondingly anterior.

The axis of rotation of the Cervicals below the Atlas is in the extreme anterior portion of their bodies. This part remains relatively fixed in rotatory subluxation while the tip of the spinous process describes the greatest arc.

In the Dorsals the axis of rotation lies in the posterior portion of the centrum near the neural canal. When the spinous process appears laterally displaced in rotation the anterior portion of the body is slightly displaced in the opposite direction, twisting and straining the fibres of the intervertebral disk.

In the Lumbar region rotation is the commonest form of subluxation, the axis of rotation being laterally movable upon a transverse line between the articular processes in the beginning and shifting, as soon as the vertebra leaves its normal relations, to the junction of the articular process with that of the adjacent vertebra on the side toward which the spinous process is moving. Thus, in rotation of the vertebra so that the spinous is to the right, the axis will be found on the right side, the superior articular process of the next vertebra serving as a support on which the inferior articular process of the rotating vertebra may turn. The processes are so firmly locked that unless the whole vertebra be quite posterior little lateral movement of the spinous process is possible without marked rotation. The body describes the greatest arc because it is further removed from the center of rotation than is the tip of the spinous.

Tipping

This is a subluxation in which the one transverse process is, or appears to be, superior or inferior to the other. It occurs frequently to the Atlas in combination with lateral subluxation. In fact, the shape of the occipito-atlantal articulations is such that, if the remaining Cervicals maintain their proper relation to each other, the Atlas cannot be laterally displaced without a certain amount of tipping. It will be relatively superior on the prominent side and the head will be tipped toward that side; that is toward the side of the lateral displacement. Thus, on account of the wedge-shaped lateral masses, if the whole Atlas be to the right of its normal position the right side will be superior and the head tipped toward the right. This is only true when the vertebrae below maintain a normal interrelation.

Approximation

This is a name applied to that condition in which, on account of changes in the intervertebral disks due to subluxation interfering with metabolic processes, the bodies or spinous processes of vertebrae are crowded too closely together.

Occasionally a spine is found in which, on palpation, the spinous processes are found to be crowded together in groups, sometimes of two or three, sometimes of five or six; no two interspaces appear equal, a very wide one being succeeded by one or two which are almost inappreciable; the variation in width of the interspaces does not correspond to the known normal variation in those regions where the changing obliquity of spinous processes should modify the relative width of successive spaces. We expect, for instance, to find a wider space between third and fourth Dorsals than between second and third; if we do not find this difference it is doubtless due to cartilage change and the vertebrae are approximated.

In case of general thinning of intervertebral substance unequally divided between different sections of the spine the record will show that almost every vertebra is listed either S or I, and if a system of underscoring is used that these two directions are frequently indicated as most noticeable.

A study of the spine will make clear the fact that if the cartilage between any two Dorsal vertebrae be thinned in front the bodies of the vertebrae will be closer together and the spinous processes more widely separated; the spinous process of the upper vertebra will be crowded against the one superior to it and that of the lower against the one inferior to it. These spinous processes are said to be _approximated_.

The correction of S or I subluxations, then, depends upon correction of disturbed nutritive processes.

Lateral Displacements

According to the usage of earlier writers on subluxations this term (lateral displacement) included rotation of the vertebra as well as those changes in position in which the whole or nearly all of the vertebra deviates sidewise from its normal position. Since the introduction of the term “rotation” into the description of subluxations, the meaning of the term “lateral displacement” is much more restricted. It refers now to a condition which probably occurs in the strictest sense only in the Cervical region, most frequently with the first and second Cervical, the two being subluxated together.

We have already stated that the most important fact to be determined regarding the Atlas is its lateral displacement, since this produces the greatest impingement of nerves. Lateral displacement of any other Cervical can best be judged by examination of the transverse processes, since by palpation of the spinous process alone it is quite impossible to distinguish between lateral and rotary subluxation.

In the Dorsal and Lumbar regions the R or L used to describe the position of the spinous process most often indicates rotation of the vertebra. While it is perfectly proper thus to describe the subluxation on a record, in the determining of the form of adjustment to be used the position of the _whole_ vertebra must be considered.

Anterior Subluxations

Forward displacements may occur anywhere in the spine. In the case of the first Cervical they are usually, though not always, forward displacements of only one side--rotation--though the whole Atlas may be anterior if the Axis has moved with it or is tipped so that the spinous process is much superior. This is rare.

Any Cervical may be anterior; usually a series are anterior (if any) amounting to an increase in the Cervical curve--a lordosis. This condition may be corrected by transverse adjustments given from the front and side.

A Dorsal vertebra is only _relatively_ anterior, the adjacent ones being relatively posterior, and the only possible correction at present is the adjustment of the posterior ones. A Lumbar cannot be anterior unless those below it are also anterior, on account of the locking of articulations. Discovery of anterior Lumbars is quite common. The fifth Lumbar may be subluxated anteriorly by slipping forward on the Sacrum; it must be _superior_ at the same time, on account of the shape of the articulating surfaces which face downward and forward. The spinous process is crowded closely against the fourth while the body of the fifth is too widely separated from that of the fourth.

Posterior Subluxations

There are many Chiropractors who have always considered the posterior subluxation more than any other, not because it produces greater nerve impingement than others but because it is easiest to detect; it intrudes itself upon the attention of the unskilled examiner most persistently. Nor should its importance be underestimated, though we now realize that in some instances a rotated or anterior vertebra may cause more nerve impingement than a posterior one.

The posterior subluxation in the lower Dorsals and Lumbars is the easiest variety to adjust; in this region a posterior displacement of one vertebra tends to bring with that one the next adjacent superior one, the sharpest deviation occurring between the posterior one and the one below it.

Any vertebra may be posterior: the Atlas is rarely so as a whole, and never unless the Axis is also displaced backward; the Cervical and Dorsal regions present frequent variations of this sort, which must not, however, be confused with long, prominent, or overdeveloped spinous processes; the Sacrum may be posterior to the ilium on one side, or to both ilia.

Occipital Subluxations

Mention should be made here of a form of subluxation not strictly vertebral--displacement between the condyles of the occipital bone and the lateral masses of the Atlas. This occurs when the head has been moved too violently upon the Atlas so as to cause an immediate nerve irritation and muscle tension sufficient to hold it in its abnormal position. The Cervicals may be quite normal below the Atlas though this, of course, is not the rule. Correction of occipital subluxations is made by applying force to the Atlas and to the skull, sometimes by holding Atlas and rotating the skull.

Age of Subluxations

The relative age of subluxations may be determined, within rather wide limits, it is true, by a study of the form of the spinous process. Newly acquired subluxations are sharply defined, having noticeable _edges_ on the spinous process. In time they tend to become rounded and blunt and appear to cover more surface, just as the mountain range which, when first upheaved, is sharp and rugged, gradually rounds into regular curves through the work of the elements.

In this way Nature protects the subluxated vertebra from further contact with the environment surrounding man, the rounded process offering less opportunity for a blow or shock to affect it.

Changes in Shape

Bone diseases such as rachitis osteomalacia, etc., and especially Potts’ Disease, or spinal caries, make marked changes in the shape of vertebrae. Also a subluxated vertebra may gradually assume a shape suited to the abnormal position it occupies, the commonest change being the assumption of a wedge shape by the centrum. This is a great obstacle to adjustment, as the abnormal shape of the vertebra makes it tend to settle after each movement into the old abnormal position.

There are few spines without some more or less misshapen vertebrae.

Ankylosis also makes great changes in the shape of vertebrae. There are two kinds of ankylosis--true and false. The first is a deposit of bone cells upon bone, often the formation of a bridgelike structure to hold contiguous vertebrae together. This may bind any portions of the vertebrae but most commonly holds the bodies, in which case it can only be appreciated by detecting the lack of movement between normally separable vertebrae. False ankylosis occurs with fever in bone and consists in an exudation of bone substance which sometimes produces remarkable distortions of shape.

TECHNIC OF ADJUSTING

Definitions

Vertebral Adjusting is the art of correcting by hand the malpositions of subluxated vertebrae.

A Vertebral Adjustment, strictly speaking, should mean the complete restoration of normal relation between previously subluxated vertebrae. As used in Chiropractic, it means either a partial or complete restoration of such normal relation.

Maladjustment, as used in the profession, designates any movement of vertebrae by hand which produces or increases subluxation.

GENERAL PRINCIPLES OF ADJUSTING

It will be well for the student to master first the general rules and principles which govern vertebral adjustment and then to proceed to a detailed investigation of each movement, in turn, before practicing it. The art of adjusting can only be acquired by practice, and a high degree of excellence in it only by _long-continued_ practice. However, the rapidity with which it can be mastered depends largely upon the formation of a clear pre-conception of the work to be done and the manner of its doing.

As the student progresses in the art he finds himself occasionally guilty of errors which mar, in some degree, the efficiency of his work. These may arise from unconscious modification of the technic first learned or from unconscious repetition of some necessary modification demanded by a special peculiarity in one or more cases.

This section is intended to furnish the proper pre-conception and also to serve as a monitor to adjusters who, by reference to the precepts herein set down, may discover and remedy their own errors. It is not intended to furnish sufficient education to warrant practice without clinical instruction, which is unwarrantable, but rather to accelerate the education which practice alone can furnish.

Object of Adjustment

The vertebral subluxation being an abnormality of _relation_ between vertebrae, it is obvious that its correction must be a return of normal relation. This can only be accomplished by bringing about a change of _relative_ position. Movement of a section of the spine composed of several vertebrae is not, in the true sense, an Adjustment. It is the _single_ vertebra which must be moved.

The movement should be one calculated to bring the vertebra to its normal position _in the most direct manner possible_. Such a movement should be used as will reverse the direction of the forces which subluxated the vertebra. It should be applied to the transverse or spinous processes, or to the lamina, as is sometimes done in the case of the Atlas, according to the _kind_ of subluxation. Different subluxations require different handling. Cases vary. Select the move _best suited to the case_. This can be determined most properly by correct palpation which fixes in the mind of the adjuster the position of every part of the vertebra, its relation to its fellows, the points of greatest nerve impingement, etc., all of which should suggest the best method for correction.

The prime object of adjustment is the removal of impingement from nerves.

Transmitted Shock vs. Thrust

The movement used in adjusting has been variously described. Many writers and teachers have used the term “thrust” to describe the movement of the hands, and the term is correctly applied to the movement used by many Chiropractors. But a careful study of the methods of applying force in use among the most successful adjusters, those who have attained the greatest results with the slightest percentage of failures and a minimum of pain to the patient, discloses the fact that the chief element of their adjustment is _transmitted shock_.

The hand is held in close contact with the vertebra to be adjusted and the arms and shoulders describe such movements as to deliver the required amount of force with the slightest possible change in the position of the hands. The vertebra bounds away from the contact hand. In the delivery of a _thrust_ the hand would follow the vertebra, forcing each portion of the movement. The real effect of a thrusting motion, since the hand cannot enter the body as a sharp instrument would, is that of _pushing_. Pushing neither subluxates nor adjusts vertebrae so readily as does a rapidly applied shock.