30 Pied tabétique—Revue de Médecine, 1884, p. 473.
There is less dispute concerning the nature of the so-called perforating ulcer of the foot. This lesion occurs only in cases where the central or peripheral nervous apparatus is diseased; thus, it may occur with neuritis, and it is therefore unanimously regarded as due to morbid nervous influences. In tabes it may follow an exacerbation of the fulminating pains. It consists in a swelling of the tissues of the foot; the skin becomes firm and thickened; deep sinuous ulcers are then developed, showing but slight if any tendency to granulate, and which extend down to the bone, the latter usually remaining unaffected.31 In a few cases more remarkable accidents due to disturbed nutrition have been noted. Thus, J. Hoffmann records a subcutaneous rupture of the Achilles tendon, and in another case the spontaneous discharge of all the teeth of the upper jaw within about a week's time.32
31 Like most of the manifestations of advanced tabes, the perforating ulcer may occur exceptionally as a pre-ataxic symptom. Thus, Suckling (British Medical Journal, 1885, April 4, p. 693) mentions its preceding the development of tabes proper by one year.
32 Berliner klinische Wochenschrift, 1885, No. 12. In this unique case the loosening and falling out of the teeth preceded the tabes by a year. Demange, who observed the same phenomenon in two cases, found that the ascending root of the fifth pair was involved. The only analogous observation in my experience relates, like the bleaching of the hair in circular patches, to a case of spinal irritation: here the gums and alveolar borders underwent atrophy, exposing the roots of the teeth to beyond the normal alveolar border: first the right upper row, then the right lower row, and finally the teeth on the left side in the same order, showed this condition; only the most posterior fell out.
COURSE.—Tabes dorsalis is to be regarded as an extremely chronic affection. Its development, as previously stated, is insidious,33 and the symptoms demonstrating the advent of the disease may be so slight for many years that the patient does not regard himself as ill or as likely to become so. In this condition he may remain for ten or more years; and there are cases recorded where the exact signs of the incipient stage were well marked, and yet no ascertainable progress was made in a period of such long duration that the inference naturally follows of a much longer prospective period in which the patient would not have become ataxic. There may be distinguished two forms of invasion: the more frequent is marked by the development of the terebrating, fulgurating, and fulminating pains, to which, sooner or later, the abolition of the pupillary and certain other deep reflexes is added. In the vast majority of cases they are found absent when the physician's attention is directed to the question of the existence of spinal disease. In about one-fifth of the cases pain is at no time a prominent feature of the disease, and may be, as is established by the cases cited, entirely absent. In these patients the first symptoms noted are muscle-tire on slight exertion. Usually, the evidences of disturbed sensation and innervation begin in one extremity or preponderate in it, but symmetry is soon established. The same is noticed in the extension of the morbid process: when the ulnar distribution is involved—which is the first danger-signal on the part of the cervical enlargement of the cord—usually one side is first involved, but the other soon follows, and becomes affected in equal or nearly equal degree. In the overwhelming majority of cases the disease manifests itself in the lower extremities first, remaining limited to them for a long period, and if extending to the upper extremities doing so in much slighter intensity than in the lower. Gull, Leyden, and others have observed cases where the arms were first and chiefly involved; but this is extremely rare. Cases of a simultaneous involvement of the upper and lower extremities are more frequently noted. The symptoms detailed above are developed in varying order in different patients, and the line has been already indicated which separates the progressive from the episodial features of the disease. Even in the ataxic period the patients may remain in a comparatively stationary period for many months and years.34 The general bodily nutrition is usually good, and the muscular strength, as such, rarely affected to any noteworthy extent until the extreme phase of the disease is reached. Even the formidable-appearing crises and trophic disturbances, though occasionally fatal, are not always so. The direct danger from the disease proper, so far as life is concerned, is in the possible development of cystitis and pyelitis, of the malignant bed-sore, and of delirium and coma, the latter of which is occasionally found to be due to cerebral hemorrhage—a lesion which some writers regard as possibly due to some impalpable influence of the spinal disease on the cerebral circulation.35
33 Cases of acute locomotor ataxia have been described. In no instance are they pure or typical, and the last case of the kind published in America, beginning, as it is evident from the account, with signs of general myelitis, illustrates the impropriety of utilizing one or a few symptoms as determining nomenclature.
34 Thirteen patients are now under my observation, or I have been able to obtain reliable medical information concerning their condition, who have been in the ataxic period since the date of my first examination, varying from a year to seven years ago. Not one of these patients is materially much worse than at that time. Two only died, both being bedridden at the time they came under observation. Of the first group, three have shown more or less lasting improvement in respect to special symptoms, as will be detailed in connection with the treatment.
35 In a case of sudden death, with an asthma-like seizure, of a tabic patient under the charge of T. A. McBride, I found an intense injection of one (the right) vagus nucleus, the color of the ala cinerea and of the nucleus on section being almost black.
MORBID ANATOMY AND PHYSIOLOGY.—Our knowledge of the structural disease underlying the symptoms which comprise the clinical picture of tabes dorsalis is perhaps the clearest in the domain of spinal pathology. Not alone the commencement of the morbid process and every stage of its subsequent encroachment on the spinal cord, but also its relations to special symptoms, have been demonstrated in numerous cases by some of the most careful German and French investigators.
In advanced cases of tabes the disease of the spinal cord is so evident that it was noted even by earlier observers, the region of the cord lying between the posterior nerve-roots being altered in color, consistency, and dimensions. It is gray instead of white, hard instead of soft, and considerably shrunken. The gray discoloration of the surface appears to be complete in the lumbar and lower dorsal region; it is less intense in the upper dorsal and cervical part of the cord; and often shows a division into three streaks, of which one, in the middle line, occupies both columns of Goll, while on either side another extends in the inner side of the posterior root-entry. The posterior roots themselves are frequently atrophied, and exhibit a firmer consistency and darker color than in health. On making cross-sections of the spinal cord it is found that the gray discoloration extends inward, involving more or less of the posterior columns in well-defined areas. Microscopic examination shows that the myelin of the nerve-tubes is either destroyed or atrophied, and the axis-cylinder is found to be affected in the same way, usually presenting alterations in its refraction and diameter where it is not entirely destroyed. In the maximum foci of disease the conducting elements of the cord are nearly destroyed, and their place is occupied by a firm connective substance made up of wavy bundles, enclosing here and there a few atrophied axis-cylinders with wasted myelin-sheaths. The blood-vessels participate in the morbid process, at least as far as the larger vessels are concerned: these are sclerotic, their lumen appears contracted, the adventitial sheath is hypertrophied and occupied by a nucleated, fibrillar connective substance. The capillaries are sometimes normal, or participate in the morbid process to the extent of a thickening of the extra-endothelial sheaths which is either hyaline or fibrillary, and may show inflammatory cell-proliferation. It is evident that the increase of connective tissue in the posterior columns is not merely a relative one, due to the condensation of the normal neuroglia after the disappearance of the normal nerve-tubes, but is the result of actual proliferation. Opinion is somewhat divided as to whether this is to be considered as an inflammatory interstitial proliferation or as a more passive development of tissue compensating for the destroyed conducting elements. My own observations incline me to the belief that in syphilitic tabes the morbid process is essentially interstitial, while in non-syphilitic tabes it is parenchymatous, the disease beginning in the nerve-tubes proper. Perhaps the controversies between pathologists as eminent as Schultze, Tuczek, Rumpf, Zacher, Kahler-Pick, Rosenstein, and Adamkiewicz—who are rather evenly divided into opposing camps, one maintaining the parenchymatous, the other the interstitial, origin of the disease—may be solved when we learn to distinguish between the non-syphilitic and syphilitic cases, which is clinically, as yet, impossible. The difficulty of deciding what is a parenchymatous and what is an interstitial disease of the cord is considerably enhanced by the fact that the neuroglia, which by some at least is regarded as an interstitial connective tissue, is derived, like the nerve-substance proper, from the upper or neuro-epidermic germ-layer of the embryo, and not from the mesoblast, which furnishes all other connective substances in the body.