CLINICAL HISTORY.—The development of tabes dorsalis is typically slow and its precise commencement usually not determinable. In some cases this or that one of the characteristic symptoms of the disease preponderates from the beginning, and continues throughout the illness as a prominent feature; in others distinct stages can be recognized, each marked by one or several symptoms which were absent or slight in the other stages. In some cases the progress of the affection is marked by episodes which are absent or rare in other cases. As a rule, however, it may be stated that tabes is a progressive affection, marked by pronounced temporary changes for better or worse, which are often developed with astonishing rapidity, and subside as quickly, terminating fatally unless its progress be arrested by treatment or interrupted by some other fatal affection. The latter is by far the more frequent termination in the well-to-do class of sufferers.
For purposes of convenience we may consider the symptoms of the earlier period of the illness as pre-ataxic, and those of the later as the ataxic. It is to be remembered, however, that in the strictest sense of the term there is usually some disturbance of co-ordination even in the early period, while the symptoms of the pre-ataxic period continue over the ataxic period, and may even become aggravated with it. Often the patient does not himself suspect a spinal, or indeed any nervous, disorder, and consults the physician either on account of rheumatic pains, double sciatic neuralgia, bladder disturbance, diminished sexual power, amaurosis, diplopia, or even gastric symptoms, which on closer examination are revealed to be evidences of tabes. The determination of the initial symptoms is retrospective as a rule.
Of the subjective signs, one of the commonest, if indeed it be ever entirely absent, is a tired feeling, particularly noted in the knees and ankles. This sensation is compared to ordinary muscle-tire, but is provoked by slight exertion, and not as easily remedied by rest. Often a numb feeling is associated with it, although no objective diminution of cutaneous sensation be determinable. This combined feeling of tire and numbness, described as a going-to-sleep feeling in the ankle, has indeed been claimed by one observer1 to be pathognomonic of early tabes. Next in frequency, and almost as universal, are peculiar pains: these are manifold in character and distribution, but so distinctive as to alone suggest the existence of the disease from the manner in which the patient describes them. One variety, the lightning-like, is compared to a sudden twinge of great intensity shooting through the limb. The sciatic and anterior crural branches are the lines usually followed by this pain, but there are cases where perineal and abdominal regions are affected. Often the pain is so severe that the patient cries out or the limb is violently contracted under its influence. It differs from rheumatic pain in the fact that it is distinctly paroxysmal and that the intermissions are complete; that it is not greatly aggravated by motion nor relieved by rest, while the rheumatic pain is; that tabic pain is usually relieved, and rheumatic pain aggravated, by pressure, while hyperæsthesia is present with the former, and either absent or barely indicated with the latter. The lightning-like pains are sometimes combined with another form, which is even more distinctive in character. This form does not affect the distribution of special nerves, but is found limited to a small area which the patient is able to localize definitely: it may not exceed a centimeter or two in diameter, and within this area the pain is excruciating. It is either of a burning character or compared to the firm pressure of a vise or heavy weight, or to the tearing, boring, and jumping of a violent toothache.
1 Canfield, Lancet, 1885, vol. ii. p. 110.
While some patients escape these pains almost entirely,2 others are tormented with them at intervals for years, their intensity usually diminishing when the ataxic period is reached. There is little question among those who have watched patients in this condition that their pains are probably the most agonizing which the human frame is ever compelled to endure. That some of the greatest sufferers survive their martyrdom appears almost miraculous to themselves. Thus, in one case the patient, who had experienced initial symptoms for a year, woke up at night with a fulminating pain in the heels which recurred with the intensity of a hot spear-thrust and the rapidity of a flash every seven minutes; then it jumped to other spots, none of which seemed larger than a pin's head, till the patient, driven to the verge of despair and utterly beside himself with agony, was in one continued convulsion of pain, and repeatedly—against his conviction—felt for the heated needles that were piercing him. In another case the patient, with the pathetic picturesqueness of invalid misery, compared his fulminating pains to strokes of lightning, “but not,” he added, “as they used to appear, like lightning out of a clear sky, but with the background of a general electrical storm flashing and playing through the limbs.”
2 I have at present under observation two intelligent patients (one of whom had been hypochondriacally observant of himself for years) who experienced not a single pain, as far as they could remember, and who have developed none while under observation. Seguin mentioned a case at a meeting of the Neurological Society with a record of but a single paroxysm of the fulgurating variety. Bramwell (Brit. Med. Journ., Jan. 2, 1886) relates another in which the pains were entirely absent.
Either while the pains are first noticed or somewhat later other signs of disturbed sensation are noted. Certain parts of the extremities feel numb or are the site of perverted feelings. The soles of the feet, the extremities of the toes, the region about the knee-pan, and the peroneal distribution, and, more rarely, the perineum and gluteal region, are the localities usually affected.3 In a considerable percentage of cases the numbness and tingling are noted in the little finger and the ulnar side of the ring finger; that is, in the digital distribution of the ulnar nerve. The early appearance of this symptom indicates an early involvement of the cord at a high level. Some parallelism is usually observable between the distribution of the lightning-like pains when present and the anæsthesia and paræsthesia if they follow them. With these signs there is almost invariably found a form of illusive sensation known as the belt sensation. The patient feels as if a tight band were drawn around his body or as if a pressure were exerted on it at a definite point. This sensation is found in various situations, according as the level of the diseased part of the cord be a low or high one. Thus, when the lower limbs are exclusively affected or nearly so the belt will be in the hypogastric or umbilical region; if the upper limbs be much involved, in the thoracic region; and if occipital pain, anæsthesia of the trigeminus, and laryngeal crises are present, it may even be in the neck. Correspondingly, it is found in the history of one and the same patient: if there be a marked ascent—that is, a successive involvement of higher levels in the cord—the belt will move up with the progressing disease. This occurrence, however, is less frequently witnessed than described. In the majority of cases of tabes disturbances of the bladder function occur very early in the disease. Hammond indeed claims that in the shape of incontinence it may be the only prodromal symptom for a long period.4
3 In the exceptional cases where the initial sensory disturbance is marked in the perineal and scrotal region I have found that the antecedent fulminating pains had been attributed to the penis, rectum, and anal region; and in one case the subjective sense of a large body being forcibly pressed through the rectum was a marked early sign.
4 New England Medical Monthly, 1883.