Osteopaths are not the first or only physicians who have used the spine as a means of diagnosis as well as an area upon which to concentrate therapeutic methods.  It is interesting and instructive to note the steps in the development of the knowledge of spinal conditions and of the indica-tions of remote functional disturbances which are registered there.

    Subjective Symptoms. - Subjective symptoms precede any attempt to discover objective evidences of disease.  It was early noted by physicians that patients could not be re-lied upon to interpret their own symptoms.  This led to efforts to discover symptoms which were independent of the patient's imperfect perceptions.  Palpation would naturally be used at the areas complained of by the patient.  Since the brain takes cognizance of only the peripheral areas of distribution of sensory nerves, instead of the whole course of the nerve fibers, the physician might still be misled in applying palpation, because he would be largely governed by the patient's sensory impressions.  Palpation made with reference to a realizing sense of the distribution and function of the nervous system, becomes a more satisfactory means of diagnosis.  As the knowledge of the nervous system increased, attention was called more and more to the spinal column, on account of its relations to the great nervous mass within it.  Palpation of the spinal column demonstrated the existence of sensitive areas, associated with visceral or other disorders; therefore, hyperaesthetic areas are the first diagnostic points mentioned in medical literature, in regard to the spinal lesions Such hyperaesthetic areas were considered as evidence of spinal irritation; that is, irritation of the spinal cord.

    Irritation of the Spinal Nerves. - The first reference to spinal irritation which I have found is contained in a monograph entitled "A Treatise on Neurologic Diseases Dependent on Irritation of the Spinal Marrow and Ganglia of the Sympathetic Nerve," by Thomas Pridgin Teale, 1834.  He quotes a letter from Mr. R. P. Player to the editor of the Quarterly Journal of Science "On Irritation of the Spinal Nerves," dated December 10, 1821, as follows: "I take the liberty to submit to your notice a pathological fact which has not, to the best of my knowledge, been generally remarked and attention to which, so far as my own experience goes, promises some diminution of those difficulties with which the healing art has to contend.  Most medical practitioners who have attended to the subject of spinal disease, must have observed that its symptoms frequently resemble various and dissimilar maladies and that commonly every function of every organ is impaired whose nerves originate near the seat of the disorder.  The occurrence of pain in distant parts forcibly attracted my attention and induced frequent examinations of the spinal column; and after some years' attention, 1 considered myself enabled to state that in a great number of diseases morbid symptoms may be discovered about the origins of the nerves which proceed to the affected parts, or of the spinal branches which unite; and that if the spine be examined, more or less pain will commonly be felt by the patient on the application of pressure about or between those vertebrae from which such nerves emerge.

    Spinal Treatment. - "This spinal affection may, perhaps, be considered as the consequence of diseases, but of its existence at their commencement any one may satisfy himself; and this circumstance, combined with the success which has attended the employment of topical applications to the tender parts about the vertebrae, appears to indicate that the cause may exist there.  Prejudice sometimes operates against ideas of connection so remote; but in many instances patients are surprised at the discovery of tenderness in a part, of whose implication and disease they had not the least suspicion."

    Control of the Body by the Nervous System. - Dr. Teale brings to his aid in the exposition of his subject, some interesting corroboratory observations made by others and recorded in the medical literature of that period.  He quotes Dr. Darwell in an interesting paragraph which is a faint distant undercurrent of Dr. A. T.  Still's oft-repeated statement concerning the interaction of nerves and the blood stream.  The passage is as follows: "If, however, the nervous system is more or less connected with every function of the animal body; if the circulation of the blood, the phenomena of the respiration and the operation of intellect, cannot be carried on without its intervention, the manner in which it is disregarded can not but be a most important defect.  It has perhaps in great measure arisen from always contemplating the brain as acted upon by the circulation and never reversing the order of review."

    A Concept of the Nervous System. - One of the best expressed concepts of the nervous system I have read, is Dr. Teale's introduction to his monograph.  It is the concept which is being more clearly taught in osteopathic colleges than in those of other schools of medicine: "The term Neuralgia which was originally employed to designate certain affections of nerves attended with severe pain has of late with great propriety been extended from its original and literal signification, to many other morbid affections of nerves, which are not characterized by pain, but by some other perverted state of their functions."

    Neuralgia. - "Neuralgia includes within its range a great variety of diseases, presenting an endless diversity both in their symptoms and in the parts where they are seated.  That such variety should exist, ceases to excite surprise, when we consider how varied are the functions of the different nerves and how diversified the tissues and organs to which they are distributed.

    "To the attentive observer of diseases, neuralgic affections, under the more extended signification, must repeatedly present themselves.  The skin, for instance, may be the seat of every degree of exalted or diminished sensibility, from the slightest uneasiness to the most acute suffering and from the most trivial diminution of sensibility to the complete obliteration of feeling, - symptoms not dependent upon disease affecting the different tissues of the part but solely referable to a morbid condition of the sentient nerves.  The voluntary muscles may in like manner indicate in a variety of ways a morbid condition of the nerves with which they are supplied.  They may be affected with weakness, spasms, tremors, or a variety of other disordered states included within the two extremes of convulsion and paralysis.  The involuntary muscles may have the harmony of their actions interrupted from a morbid condition of their nerves; the heart may be affected with palpitation; the vermicular motion of the stomach or the peristaltic action of the intestines may be subject to irregularity.  The sensibility of the internal organs may like-wise be affected, the heart, the stomach, the intestines, being the seat of pain, referable to their nerves, and independent of inflammation, or any alteration of structure.  The secretions may also undergo alterations, both in quantity and quality, from a perverted agency of the nerves upon which they depend.  Such is a very imperfect recital of the various morbid affections which may be included under the term Neuralgia, and so frequent is their occurrence that they must be familiar to every practitioner.  They are, however, often perplexing in their treatment and not unfrequently exhaust the patience of the afflicted sufferer, and also of the medical attendant.

    "The difficulty and embarrassment which have attended the diagnosis and treatment of these affections, I am inclined to believe, has principally arisen from mistaken views of their pathology.  They have too often been regarded as actual diseases of those nervous filaments which are the immediate seat of the neuralgia instead of being considered as symptomatic of disease in the larger nervous masses from which those filaments are derived; hence the treatment has too frequently been ineffectually applied to the seat of neuralgia ; instead of being directed to the more remote and less obvious seat of disease.

    "It is now pretty generally admitted as a pathological axiom, that disease of the larger nervous masses, as the brain and spinal marrow, is not so much evinced by phenomena in the immediate seat of disease, as in those more remote parts to which the nerves arising from the diseased portion are distributed.  In the more severe forms of disease, this principle is readily admitted and recognized.  When for instance one-half of the body shall have lost its sensibility and the corresponding muscles their power of action, the skin and the muscles are not regarded as the seat of disease, but the brain is immediately referred to.  In the slightest forms of disease of the brain and spinal marrow, such as do not completely obliterate but merely impair or pervert the functions of the nerves - such as do not paralyze the sentient and muscular powers of the part but produce weakness, tremors, spasms, etc., ill the muscular system, and numbness and prickings, pains and other morbid feelings in the nerves of sensation, this important principle, which as strictly obtains as in the former instance, is too often entirely overlooked; and a numerous class of complaints of very frequent occurrence, are regarded as nervous or spasmodic diseases of the part affected, instead of being considered as actual diseases of that portion of the brain and spinal marrow from which the nerves of the part are derived.

    Visceral Disturbance Due to Disturbed Nerve Control. - "The same pathological principle is, I believe, equally applicable to the sympathetic system of nerves; although it may be difficult to establish this opinion by actual experiment, yet I think it may be rested upon a well grounded analogy, which will justify us in regarding the nervous masses of the ganglionic system as bearing the same relation to the nerves derived from them, as the large nervous masses of the cerebro-spinal system bear to their respective nerves.  Hence many nervous affections of the viscera ought not be considered as diseases of the viscera themselves but as symptomatic of disease in those particular ganglia whence their nerves are derived.

    Co-existence of Spinal Tenderness. - "Influenced by such considerations, I have for a few years been in the habit of treating many of these nervous affections as diseases of some portion of the spinal marrow or ganglia; and leave been still further confirmed in my opinion by the frequent and almost uniform coexistence of tenderness on pressing some portion of the vertebral column and the circumstances of the tender portion of the spine being in a particular situation where the nerves of the affected part originate.

    Symptoms of Spinal Irritation. - "The symptoms of spinal irritation consist in an infinite variety of morbid functions of the nerves of sensation and volition which have their origin in the spinal marrow, and the parts in which these morbid functions are exhibited, of course, bear reference to the distribution of the spinal nerves.

    "The morbid states of sensation include every variety, from the slightest deviation from the healthy sensibility of any part, to the most painful neuralgic affections oil the one hand, and to complete numbness or loss of feeling on the other; including pains which may be fixed or fugitive or darting in the direction of the nerve, pricking and tingling sensations, a sense of creeping in the skin, of cold water trickling over it, and numerous other states of perverted sensation of which words are inadequate to convey a description.  In the muscular system we find weakness or loss of power, tremors, spasms or cramps and sometimes a tendency to rigidity.

    "These symptoms sometimes exist in so slight a degree that the patient considers them unworthy of notice, and only admits their existence when particular inquiry is made respecting them; the only complaint which he makes being of an unaccountable sense of weakness and inability of exertion.  In other cases the tremors have excited alarm; sometimes the neuralgic pains in the scalp or the fixed pain in the muscles, particularly when it occurs in the intercostal muscles, have suggested the idea of serious disease in the brain or in the lungs; and when the pain is seated in the muscles of the abdomen, a fear that some organic disease of the abdominal viscera has taken place harasses the mind of the patient.  The muscular weakness in some cases lending to paralysis often suggests the fear of apoplexy or paralysis from cerebral disease.

    Duration of Affections Due to Spinal Irritation. - "The affection is often of very protracted duration, undergoing alternate variations from the sanative powers of the constitution and the different existing causes of disease.  There are many individuals in whom the complaint has existed, in varying degrees of intensity for a series of years, without its real nature having been suspected; the patients and their medical attendants having regarded it throughout as a rheumatic or a nervous affection.

    "In this complaint tenderness in the vertebral column which corresponds to the origin of the affected nerves, is generally in a striking and unequivocal manner evinced by pressure.  In some instances the tenderness is so great that even slight pressure can scarcely be borne, and will often cause pain to strike from the spine to the seat of spasm or neuralgia.

    "This affection of the spinal marrow occasionally exists throughout its whole extent; more frequently, however, it is confined to some particular portion, and occasionally is seated in different and remote portions at the same time; the particular symptoms and tenderness on pressure indicating the affected part.

    "The symptoms of course vary considerably, according to the particular part of the spine which is affected, and bear reference to the distribution of the different spinal nerves.

    Affections of the Upper Cervical Region. - "When the upper cervical portion of the spinal marrow is diseased, we frequently find neuralgic affections of the scalp; the pain strikes in various directions over the posterior aid lateral parts of the head; sometimes the twigs in the neighborhood of the ear, sometimes those which ascend over the occiput to the superior part of the scalp, are more particularly the seat of the complaint; the nervous twigs distributed to the integuments of the neck are occasionally affected, the pain darting across the neck to the edge of the lower jaw, and sometimes encroaching a little upon the face.  These neuralgic diseases frequently assume an intermittent form, the paroxysms generally occurring in the evening.  A stiff neck or impaired action of the muscles moving the head frequently attend the affection of the upper cervical portion of the spinal marrow; and occasionally the voice is cornpletely lost, or suffers alternation, and the act of speaking is attended with pain or difficulty.

    Irritation of the Lower Cervical Region. - "Irritation of the lower cervical portion of the spinal marrow gives rise to a morbid state of the nerves of the upper extremities, shoulders, and integuments at the upper part of the thorax.  Pains are felt in various parts of the arm, shoulder, and breast; sometimes the pain takes the course of the anterior thoracic branches of the brachial plexus, occasionally the pain is fixed at some point near the clavicle, scapula or shoulder joint at the insertion of the deltoid, or near the elbow or shoots along the course of some of the cutaneous nerves.  Frequently one or both of the mammae become exquisitely sensible and painful on pressure, and some degree of swelling occasionally takes place in the breast, attended with a knotty and irregular feeling, when the neuralgic pains have existed a considerable time in the that part, prickling and numbness are often felt in the upper extremities; and also a sensation of cold water trickling over the surface.  On rubbing the hands over the part affected a soreness is frequently felt, which is described as not merely situated in the integuments but also in the more deep seated parts.  In the muscular system are observed most frequently a weakness of the upper extremities sometimes referred particularly to the wrists, tremors and unsteadiness of the hands; also cramps and spasms of various degrees of intensity.  Occasionally there is an inability to perform complete extension of the elbows, the arm appearing restrained by the tendon of the biceps; and tightness being produced in this part when extension is attempted beyond a certain point.  As far as I have observed, the pain and other morbid feelings in the upper extremities and chest are felt more frequently and more severely oil the left than on the right side.

    "Females of sedentary habits appear particularly subject to these affections of the upper extremities, and it is not uncommon for them to complain of being scarcely able to feel the needle when it is held in their fingers, and that their needles and work frequently drop from their hands.

    Irritation in the Upper Dorsal Region. - "When the upper dorsal portion is affected, in addition to various morbid sensations similar to those in the extremities, there is often a fixed pain in some part of the intercostal muscles, to which the name pleurodynia has been assigned; and when this pain has existed a long time, there is tenderness on pressing the part.

    Irritation in the Lower Dorsal Region. - "When the lower dorsal half of the spinal marrow is the seat of irritation, or subacute inflammation, the pleurodynia, when it exists, is felt in the lower intercostal muscles; frequently there is also a sensation of a cord tied round the waist; and oppressive sense of tightness across the epigastrium and lower sternal region; and soreness along the cartilages of the lower ribs or in the course of insertion of the diaphragm.  Various pains, fixed and fugitive, are also felt in the parietes of the abdomen, throughout any part of the abdominal and lumbar muscles; the pain is frequently fixed in some portion of the rectus muscle and not infrequently in the oblique muscle or transversalis, a little above the crest of the ilium, particularly when the origin of two or three of the lowest dorsal nerves is diseased.

    Irritation in the Lumbar and Sacral Regions. - "The affection of the lumber and sacral portion of the spinal cord often produces a sensation of soreness in the scrotum and neighboring integuments; and the lower extremities become the seat of various morbid sensations, spasms, tremors, etc., for the most part resembling those which have been described as occurring in the upper limbs.  The patients also complain of a sense of insecurity or instability in walking; their knees totter, and feel scarcely able to support the weight of the body.

    The Effect of Recumbency. - "In some cases very considerable relief is found from recumbency,, the pain frequently being diminished as soon as the patient retires to bed, independently of any paroxysmal remission.

    Irritation of Spinal Marrow Not Necessarily Dependent on Disease of Vertebrae. - "This irritation or subacute inflammatory state of the spinal marrow is not necessarily connected with any deformity of the spine, or disease in the vertebrae.  It may co-exist with these as well as with any other diseases, but it so repeatedly occurs without them that they can not be regarded as dependent upon each other.  Where, however, inflammation and ulceration of the vertebrae or intervertebral cartilages exist, it is probable they may predispose to, and in some instances, act as an exciting cause of an inflammatory state of the nervous structures which they contain; for we not frequently find inflammatory affections of the vertebrae in conjunction with symptoms of irritation of the spinal marrow.  But these two affections, although coexisting, bear no regular relations to each other; and during the progress of the vertebral disease the affection of the nervous structures is subject to great changes and fluctuations.  The local remedies employed for arresting the disease in the bone often alleviate the affection of the spinal marrow at the very commencement of the treatment, long before the vertebral disease is suspended; but as the neighboring inflammation in the bones appears to predispose or excite the nervous mass which they contain to disease, relapses of the nervous affections are repeatedly occurring during the whole course of the complaint.

    Lateral Curvature. - "The affections of the spine, termed lateral curvature and excurvation, appear to have no necessary connection with the disease which I have been describing; and the proportion of cases in which they are found united is so small that lateral curvature can scarcely be considered even as predisposing to this disease.  The most extreme degrees of deformity are frequently observed without any affection of the nerves; and when lateral curvature does occasionally co-exist, local antiflogistic treatment will often speedily remove the nervous symptoms while the curvature remains unrelieved.  Hence there is an impropriety in considering these nervous symptoms as a result of the deformity and in explaining them upon the mechanical principle of pressure and stretching, to which the nerves are supposed to be subjected as they issue from the intervertebral foramina.  If the pressure and stretching produced by the curvature were the cause of the nervous symptoms, they ought to continue as long as the deformity remains.

    Treatment. - "When the different neuralgic symptoms which have been enumerated can be traced to this morbid state of some portion of the spinal marrow, the treatment that ought to be pursued is readily decided upon.  Local depletion by leeches or cuping, and counter irritation by blisters to the affected portion of the spine, are the principal remedies.  A great number of the cases will frequently yield to the single application of any of these means.  Some cases which have even existed several months I have seen perfectly relieved by the single application of a blister to the spine, although the local pains have been ineffectually treated by a variety of remedies for a great length of time.  A repetition of the local depletion and blistering is, however, often necessary after the lapse of a few days, and sometimes is required at intervals for a considerable length of time.  In a few very obstinate cases issues or setons leave been thought necessary; and where the disease has been very unyielding, a mild mercurial course has appeared beneficial.

    "When my attention was first directed to this subject, I considered recumbency a necessary part of the treatment; it is, for a moderate length of time, undoubtedly beneficial and frequently very much accelerates recovery, but subsequent observation has convinced me that it is by no means essential.  I have seen several instances of the most severe forms of those complaints occurring in the poorer classes of society, where continued recumbency was impracticable, which have, nevertheless, yielded without difficulty to the other means of the treatment, whilst the individuals were pursuing their laborious avocations.

    "These observations, however, arc not intended to apply to those cases in which there is actual disease of the vertebrae.

    "When there exists a tendency to relapse, I have thought it advantageous to continue the use of some stimulating liniment to the spine for a few weeks after the other means of treatment have been discontinued.  A liniment consisting of one part spirits of turpentine and two of olive oil is what has generally been employed.

    Ganglia of the Sympathetic Nerves. - "The ganglia of the sympathetic nerves appear subject to a state of disease which have been described in the preceding chapter, as occurring in the spinal marrow.

    "As the disease may be confined to one part of the spinal marrow, or exist simultaneously in different portions, or may even pervade its whole extent, so the affection of ganglia may be confined to one of these nervous masses, may exist in several which are contiguous, or in ganglia remote from each other; and as there is reason to believe the whole chain may occasionally be affected.

    "The disease of the ganglia is seldom found, except in conjunction with that of the corresponding portion of the spinal marrow, whereas the spinal marrow is often affected without the neighboring ganglia being under the influence of disease.  Thus we frequently find symptoms of disease in a portion of the spinal marrow without any evidence of its existence in the corresponding ganglia, frequently the symptoms of both combined, and occasionally, but rarely, symptoms referable to the ganglia without spinal marrow being implicated.

    Symptoms of Irritation of Sympathetic Ganglia. - "The principal symptoms resulting from irritation of the ganglia of the sympathetic are to be found in those organs which derive their nerves from this source.  They consist of perverted functions of these organs, and are exemplified by a variety of phenomena.  The involuntary muscles, deriving their power from the sympathetic, have their action altered as is evinced by spasms and irregularity in their contractions.  The heart is seized with palpitations, the large vessels with inordinate pulsations; the muscular fibers connecting with the bronchial apparatus are thrown into spasms, constituting a genuine asthma independent of bronchial inflammation.  The muscular fibers of the stomach and intestines become the seat of spasms and various other deviations from their natural operation.  The sensibility of the organs, which derive their sentient power from the great sympathetic, is variously perverted, the nervous filaments being the seat of pain.  The heart and lungs, for instance, are subject to morbid sensations bearing great analogy to those which have been designated  'tic douloureax' when occurring in the spinal nerves.  The stomach and intestines are liable to similar neuralgia, to which the names gastrodyma and enterodyma have been applied.  The kidneys, the bladder, and the uterus are liable to the same perverted state of their sensibility.  The secretions also undergo alterations, products being formed, which in health have no existence.  This is exemplified by the enormous secretions of air which sometimes occur in the stomach.  Large quantities of clear transparent liquid are also secreted by this organ, constituting what is called pyrosis.  The secretions of the stomach undergo variation in their quantities, rendering them unfit for digestive process.  It is probable that the secretion of the liver also experiences some alteration in these complaints.  The urine is sometimes influenced, and I am inclined to suspect that some forms of diabetes partake of neuralgic character.  Leucorrhea is frequently a concomitant of these diseases, and ceases on their removal; but I am not prepared to say that it is ever symptomatic of them.  Irregularities in the catamenia are often observed, the discharge often being generally, in excess.

    Middle and Lower Thoracic Sympathetic Ganglia. - "The ganglia most liable to the disease are the middle and lower thoracic, from which the splanchnic nerves are derived, giving rise to various disorders of the stomach and digestive organs, which will hereafter be more fully discussed.  Next in frequency is the affection of the cervical ganglia, producing painful and spasmodic states of the heart.  The symptoms denoting disease of other ganglia, although occasionally met with, are less frequent in their occurrence.  Irritability of temper and depression of spirits often attend these complaints, particularly when the stomach is the part which suffers.

    "The disease of the ganglia, like that of the spinal marrow, is not necessarily connected with disease of the vertebrae or distortion of the spine.  It may co-exist with these complaints, and, when it does so, the symptoms proper to the ganglionic disease are often erroneously supposed to be produced by distortion or by disease of the vertebrae; they are, however, frequently relieved by treatment, whilst the disease of the bones remains uninfluenced by it, and the most extreme distortion of the spine or destruction of the vertebrae from inflammation may exist without there being any symptoms attributable to neuralgia of the sympathetic nerves.

    "In conjunction with the symptoms denoting disease of the ganglia, tenderness to a greater or less degree may generally be found on pressing some part of the spine, and the tender portion invariably corresponds with the symptoms; or rather, the seat of tenderness is near the part occupied by the particular ganglia from which the nerves of the disordered organ are derived; for example, when the heart is affected the tenderness is found in some of the cervical vertebrae, and when the stomach is the seat of complaint, it is in some of the middle or lower dorsal vertebrae.

    Spinal Treatment.  Hyperaemia. - "With respect to the treatment, I have but little to add to what has been said in the preceding chapter respecting the treatment of irritation of the spinal marrow. Leeches, culping, blisters, etc., to the neighborhood of the affected ganglia constitute the essential part."

    Muscular Tension. - Following the observation of spinal tenderness came the noting of muscular tension accompanying it.  As near as I can determine from perusing medical literature, muscular tension was not recognized until after the advent of Osteopathy.  Since the attention of medical writers was called to the conditions of the spinal column called "lesions" there are frequent passages descriptive of these in medical literature.  One of the best of these references is found in Boardman Reed's work on "Diseases of the Stomach and Intestines," and is as follows:

    "Dr.  John P. Arnold has recently called attention to novel objective sign which may be recognized upon palpation over the sensitive regions along side of the spinal vertebrae, and sometimes in such regions which are not sensitive to pressure, though in all cases he maintains that the part of the body supplied by the vasomotor nerve fibres immerging in the corresponding intervertebral space will be found to present some abnormal condition.  The peculiarity described by him is, in such cases, a somewhat doughy, and in chronic ones, a gristly tense, cord like feeling of the band of longitudinal muscular fibres which run up and down on either side of the spine.  This abnormality is supposed by Arnold to be due to a contested or infiltrated condition of the muscle while the cord itself is anemic, probably in chronic cases.  Hammond believed the spinal cord to be anemic in such cases.  The findings obtained by a careful palpation over the spine should thus assist in directmg our attention to the organ or part of the body which may be suspected of being diseased.

    Digital Examination of the Spinal Area. - "You should make it a rule to examine carefully the spines of all chronic invalids by pressing deeply with the finger tips (or with the thumbs, as Flint advised) close to the vertebrae and then exert gentle traction in a lateral direction outward from the spine on either side.  The patient should be lying upon his right side while you palpate all along the left side of the vertebrae, and should then change to his left side in order that you may palpate upon the right side of the latter so that the tissues may be in the utmost condition of relaxation practicable.  In both cases you will find it best to stand in front of the patient and reach over his upper side to make palpation along the region of the upper side of the spinal column.

    "In numerous patients, especially those suffering from digestive derangements, you will be likely while palpating in the way described to recognize in the longitudinal muscles running parallel and close to the spine the tense, cord-like sensation above mentioned.  If, simultaneously with your recognition of such a condition the patient complains of sensitiveness in the same regions, the accuracy of your finding will be at once confirmed."

    The Use of Spinal Muscular Tension in Diagnosis. - The use of these tense cord-like muscles as diagnostic evidences of disease has been a constant practice of Osteopaths from the beginning of Dr. Still's work.  Judging from the quotation the true significance of these contractions has not been apprehended by the medical profession in general.  It is very evident that a contracted muscle is shorter and thicker than when relaxed, also that when contracted it exerts force to draw its extremities together.  The ends of the muscle being attached to bones forming portions of a movable articulation, a change in the relation of the bones must follow.  This change is called a subluxation and is described more in detail in another chapter.

    Cause or Effect? - Having noted that sensitiveness and muscular contraction are well recognized conditions found along the spinal column, the question arises, are these merely objective symptoms of disease or are they to a large extent causative factors in the origin and maintenance of diseased conditions of the areas of peripheral distribution of spinal nerves?  Are they causes or effects?

    They have been noted almost exclusively as efficient causes of disease.  Furthermore, osteopathic therapeutics have been administered from that standpoint with marked success.  This change in position and size of tissues is recognized as an obstruction to the movements of fluids, and therefore is a condition operating in the system to cause disease.