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.
Let us illustrate with a common experiment in physics. Suspend a number
of ivory balls by cords of equal length in such a manner that each
is in contact with its fellow and all are in a straight line. When
the balls are properly adjusted a straight line should connect their
centers. Hold one end ball firmly in the hand or with an instrument
which renders it absolutely fixed. Then strike sharply with a light
hammer. The balls will all remain stationary except the one on the
opposite end which will fly off to a distance exactly measurable
according to the force of the blow. How does this occur?
A shock is transmitted through the molecules of the ivory until it
reaches the end ball, which is not held back by another. Here the
transmitted force is expended in molar motion, the ball leaping away
from its fellows as if it had been hung alone and had been struck with
the same force.
It is well known that by placing an elbow firmly against a man’s jaw
and then sharply striking the closed fist with the other hand, open, a
very heavy blow can be given; yet the forearm, through which the shock
is transmitted, does not move.
Now ivory is very like human bone. Further, it has been demonstrated
that the law illustrated by the above experiment is equally applicable
to the movement of vertebrae. The pushing or thrusting movement _may_
move a specific vertebra, but it is probable that the chief factor in
so doing is the element of transmitted shock contained in the movement
and delivered at the instant of release of the hand from the spine at
the end of the movement.
On the other hand it is obvious that a pushing or thrusting movement
may move several vertebrae in addition to the one directly in contact
with the adjusting hand, in consequence of the way in which the spinal
segments are closely bound together. If a steady strain is used, in
which muscles and ligaments have time to act, one of three results
may occur: (a) the specific adjustment; (b) the movement of several
vertebrae at one time, which does not constitute an adjustment; (c)
the giving way of the spine at its weakest point, which may be some
distance from the point of contact with the adjusting hand, the
ligaments and muscles having communicated and diffused the strain
throughout a large area. In the latter contingency the result is
usually a new subluxation or the increase of an old one, instead of an
adjustment.
The Rapid Movement
Thus _Speed_ becomes an important factor in correct adjustment.
A good illustration of the value of speed may be taken from a pile
of stakes bound together by a cord. If a man with a hammer desires
to remove the center stake of the group, and attempts to do so with
a slow pushing movement, the result is a change of position of many
stakes, which adhere to the center stake and to each other. If, on
the contrary, he strikes a sharp, quick blow with his hammer, meeting
squarely the center of balance of the one stake, it will fly straight
from its position leaving the others unmoved. This is exactly what we
desire to accomplish with an adjustment. By the speed of the movement
we expect to move _one_ vertebra before adhesion or the contraction of
muscles or inelasticity of ligaments can diffuse the force.
Close Contact
In order to accomplish the transmitted shock it would seem wisest,
at first thought, to draw back the hand and strike the vertebra
sharply. On the contrary, it has been found advisable to place the
hand carefully in _close_ and _immediate contact_ with the vertebra
to be adjusted. Nature herself shows us the way in the delicate
shock-transmitting mechanism of the tympanum.
Also the hand of the adjuster will cover much more than merely the
spinous or transverse process which is used as a lever and to which
it is desired to transmit the shock, unless carefully placed so that
only a _small portion_ is in contact; by such a contact diffusion of
the shock is prevented and its efficiency within a limited area is
increased. A carpenter wishing to countersink a nail places in contact
with the nail head a small instrument called a countersink, which he
then strikes sharply with a hammer. The contact hand of the adjuster
represents the countersink and is used by the two arms as a passive
instrument for transmitting shock.
The close contact of the hand, which remains passive, renders the
adjustment much less painful to the patient than it would otherwise
be, and one of the prime objects in the mind of the adjuster should be
the minimizing of pain inflicted, by any means which does not lessen
the resulting benefit. Also any drawing back of the hand before the
movement warns the patient and tends to induce involuntary muscular
contraction which interferes with adjustment.
Relaxation
In an adjustment it is necessary to overcome two kinds of
resistance--the passive resistance of inertia, of ligaments, or
of superincumbent weight, and the active resistance of muscular
contraction. It is important that both forms be minimized.
The first may be lessened through the position of the patient’s
body; he is placed so that the vertebra to be adjusted is in the
freest possible position. The second is reduced to the least possible
quantity, amounting to no more than muscle tonus, by using two methods:
(a) Oral Suggestion, and (b) Muscular Suggestion.
Oral Suggestion