As a clinician, how do you know whether or not and to what extent you are changing pathology? It's easy to see an angry, red sore throat change to pink and normal. A bleeding athlete's foot may quickly change to normal skin with antifungal medication. A cataract disappears within a half-hour after the surgeon's work. Muscle spasm, when gone, is easily documented by palpation or surface EMG. Relief of pain may be perceived by the observer's eye as it studies skin changes seen by thermography, electrodermal resistance or vasomotor patterns. Unfortunately, most changes in pathology or altered physiology are blind to the observer, even with the most sensitive technologic instruments. In fact, the process of pathogenesis is, in the majority of instances, insidious and like a thief in the night sneaks up with stealth and cunning to strike down its victim. Most disease strikes without warning and is, therefore, referred to as "silent." For example, coronary disease ushering in myocardial infarction; glomerulonephritis presages a dialysis machine; cancer of all kinds, etc., are silent.
Take the example in our specialty of joint biomechanics, Farfan's "three joint complex" -- two facet joints and the intervertebral disc. Plain radiographs taken in the DC's office, even when the quality is excellent, are in the early stage of pathology, negative. In most cases it has been difficult to justify CT scan or MRI in order to establish evidence of pathology in the early stage of disease.
Even if we found early disease, we could not track it with these expensive measuring devices. Kirkaldy-Willis' text, Managing Low Back Pain contains illustrations showing pathology in various stages involving the facets and discs, including CT, MRI, tissue specimens, histology sections, schematics, charts, and diagrams. It should be remembered that by the time any pathology is visible in a plain x-ray, that the joint area is already 20 to 30 percent degenerated. You, the doctor, when seeing this on the view-box before you, may close your eyes and visualize your patient's pathology just as it is shown in this textbook. Now, how do you know your treatment is effecting some degree of change in this pathology? A number of studies exemplified by those of Robert Salter and others show evidence of actual modification toward some regeneration of degenerative joint disease. It seems that microscopic and even macromolecular improvement takes place over time, which we clinicians are able to perceive by improved symptoms, signs and performance.
Some day, perhaps technology may prove that pathology is reversing -- that premature aging of the joints due to biomechanical trauma, biochemical disease, immunologic disc reactions, etc., may be halted and the tissue regenerated to varying degrees. What we may call "youthing" of certain tissues has been demonstrated, or perhaps hinted at, by Nathan Pritikin, Robert Salter, Norman Cousins, Dirk Pearson, Norman Walker, Jack LaLane, and countless others. When blood vessels of an old man can look like that of a youth, all of us had better pay attention, especially our patients. But, it will take more than a few adjustments to help these folks.