Analysis of the Causes of Lesions. - As previously noted, the inspection of the vertebral and paravertebral tissues in almost all cases of illness involving the trunk of the body will show physical signs of compensatory reactions.  These physical signs we call "lesions." They seem to be identical in character with those which we noted as traumatic lesions, i. e., there is deviation in osseous alignment, muscular contraction and hyperaesthesia.  It may be impossible to secure from the patient any history of trauma as the foundation of this lesion, therefore two explanations are open to us; either we must willfully hold to the hypothesis that a trauma did occur of so light immediate effect as to escape the notice of the patient, or use the facts of anatomy and physiology to build up a rational theory of normal reactions.  It is much easier to declare trauma as the cause than analyze the protective reactions of the body.  This fact has led the exponents of the various forms of spinal adjustment to explain every lesion by claiming an obscure trauma as the cause.  Since no one ever goes through life without many slips, falls and other strains which can be called to mind, it is easy for the patient to be convinced that some remote experience of this kind is in fact the foundation for all the trouble.

    The Attractiveness of the Traumatic Lesion Theory. - The theory that an obscure trauma in the spinal tissues is the essential and adequate cause of bodily disorders is captivating both to the physician and the patient.  It has so many definite elements which are evident both to the mind of the physician and of the patient.  The physician's palpitating finger feels the change in osseous alignment and muscular tone.  The patient recognizes the difference in sensitiveness between this
lesion area and those outside the lesion influence.  Specific manipulation having for its aim the correction of alignment in the lesion area gives so frequently almost instant sense of relief that it is no wonder physician and patient become convinced that the hypothesis of trauma is correct.  Under the influence of such a theory as this our osteopathic literature is well spiced with statements tending to belittle the influence of all other causes of disease.  The writer wishes to emphasize the fact that lesions can be divided into two great classes, i. c., primary and secondary.  The first class is made up of those of traumatic origin and are undoubtedly causes of disorder in their areas of influences.  The second class is made up of those lesions which are physical sign of the body's efforts at adaptation and compensation.

    Classification of Lesions. - A given lesion can be classed as primary or secondary only after careful study of all those factors which constitute the history and symptomotology of the case.  Visceral lesions cause muscular contractions in the spinal area from which they receive their cerebrospinal nerve communications.  They also cause pain in areas of higher sensibility, cutaneous areas, with which they are associated by innervation from the same segment of the spinal cord.  These referred pains and contractions of spinal muscles are beginning to be recognized by specialists in pulmonary, digestive and renal diseases.  There has been no well ordered effort to coordinate the facts which lie at the foundation of these phenomena.  It is hoped that we may make for our students a beginning in this work by what is to follow.

    Examples of Secondary Lesions. - As examples of various secondary lesions we will call attention to the lesion phenomena found usually to be synchronous with involvements of some of the organs of the body.  Rather than rush into an analysis of lesions, we deem it more to the student's interest to have a clear picture of the phenomena we desire to analyze later on.  Our practitioners who are devoting much time in treating the eye recognize that in diseases of the eye and orbital tissues there are points in the neck which are rarely free from tenderness.  Along with the tenderness are found muscular contraction and malalignment, these completing our trinity of localized lesion phenomena.  Such lesions may be located as low as the second dorsal.

    The Spinal Lesion an Objective Symptom. - Disturbance of circulation in the tonsil is associated with spinal lesions.  These lesions vary in number and extent according to whether the disease process is simple and decidedly local, or is of enough severity to produce constitutional symptoms such as chill, fever, etc.  The spinal lesions multiply and intensify in proportion to the extent and severity of the disturbance of the body.  This is the case no matter in what organ or tissue our original disturbance made its appearance.  Just as the symptom complex varies according to the severity of a disease, so the spinal lesions proportion themselves in like manner.  Therefore, in this sense, spinal lesions are physical signs: objective and subjective evidence of disturbance in tissues innervated by branches of nerves from the same segment of the spinal cord.

    Visceral Reflexes. - Each viscus, or localized tissue, such as glands, mucous or serous membranes, tend to establish reflex lesions in the spinal area tissues which are supplied with nerves from the same spinal cord segment as they themselves are supplied.  In proportion to the amount of compensatory assistance required by any organ or tissue from those parts of the body ordinarily called upon for such assistance, our spinal lesion increases in extent and intensity.  As a common example of the foregoing, the stomach may fail to do its work thoroughly and thus throw added work on the small intestine and its related glands, liver and pancreas.  If these are somewhat overtaxed by their cornpensatory efforts, our spinal lesion which represented the stomach, extends further down over the spinal areas from which the liver and pancreas receive a portion of their innervation.  Such examples as this can be recognized in a majority of cases.

    Pleurisy. - Disease processes in the lungs produce spinal lesions of various kinds, according to their intensity and destructiveness.  Pleurisy produces so great contraction in respiratory muscles, which act particularly on the ribs lying over the inflamed area, that friction of the pleural surfaces at this point is reduced to a minimum.  Physicians, taking their plan from this natural compensatory contraction, frequently reinforce natural efforts by strapping over the contracted area with adhesive.  The thorax adapts itself to the state of its contents, hence when a portion of the lung is destroyed the antero-posterior diameter of the chest is lessened in proportion.  The vertebral and costo-vertebral articulations enter into this adaptive process and hence exhibit decided lesion phenomena.

    Cardiac Lesion Patterns. - In case of heart lesions the body is called upon to make extensive compensatory reactions and hence our spinal lesion phenomena may be limited to the area of the heart's innervation, or extend in proportion as the heart's condition involves the pulmonary circulation, the portal circulation or the kidney.

    Unity of the Body. - Disease processes in the pelvic viscera produce their characteristic spinal lesion phenomena just as the thoracic and abdominal organs.  The point we desire to emphasize is that the unity of the body is exemplified by the spinal lesion phenomena.  No organ or tissue can or does suffer injury without other tissues being drafted to compensate for its condition so as to maintain not only existence but the most satisfactory life of which the organism is capable.  If the spinal lesion is viewed not only as a possible cause but, also, as a quite probable effect of tissue disturbance elsewhere, we will appreciate more fully the manner in which the body strives to live up to its best.