SYSTEMATIC LESIONS OF ÆSTHESODIC SYSTEM. 601

A CLASSIFICATION OF THE DISEASES OF THE SUBSTANCE OF THE

"SYSTEMATIC LESIONS" OF THE "ESTHESODIC SYSTEM."

In the table' which I have written out for your inspection, you will perceive that the systematic lesions may affect either the æsthesodic or kinesodic systems of the spinal cord, while the focal lesions are not thus separated, since they tend to extend in a transverse direction, and thus may be found in both. As the æsthesodic system presents well-recognized and understood morbid conditions, we will first study the general effects of systematic disease which is confined either to the columns of Goll or of Burdach.

We might begin, possibly with advantage, by stating that the general results of any lesion situated back of the posterior gray horn of the cord must manifest itself, if our previous deductions are correct, by symptoms referable only to sensation and coordination. This we find to be approximately correct. We have in this type of cases anesthesia, hyperasthesia, or numbness, and also pain (usually possessing some special characteristics which are of clinical value); while coördination is unquestionably affected as well, since a peculiar

1 See the foregoing table.

disorder of voluntary movements, which constitutes true "ataxia," is usually developed. Our previous statements as to the path of the motor impulses of the cord seem to be confirmed by the absence of either spasm or true paralysis of the muscles below the lesion.

The question now arises, "Can we tell whether the disease is confined to the columns of Goll or of Burdach?" We can undoubtedly locate the lesion in the opposite side of the cord from that of the body upon which certain symptoms are well marked; but can we tell positively whether the lesion is progressing in the inner or outer column of the posterior half of the cord when both sides are simultaneously involved?

SCLEROSIS OF THE COLUMNS OF GOLL.

As regards the columns of Goll, I feel myself forced to say that I do not believe that localized disease can be positively diagnosed when confined to these columns; although, from certain pathological deductions, we can often infer that it exists, since it has been found to occur as a secondary result of those other lesions which are capable of producing an ascending or descending degenerative process in the spinal cord. As the columns of Goll are large and distinct in the cervical region of the cord, but become narrower and narrower as the lower portion of the cord is reached, the lesion of this column becomes more evident to ocular demonstration, when present, as you ascend the cord. The entire length of either column may be affected, or only portions of it. In the ascending form of secondary degeneration of these columns, the lesion is always observed above the seat of the exciting cause. This lesion has never been traced, so far as my researches go, above the "calamus scriptorius."

SCLEROSIS OF THE COLUMNS OF BURDACH (LOCOMOTOR ATAXIA).

The columns of Burdach are the seat of sclerosis more commonly than those of Goll, since this type of change progresses, as a rule, from the posterior root zones inward, and thus only affects the columns of Goll after those of Burdach

PROGRESSIVE LOCOMOTOR ATAXIA.

603

have become seriously impaired. In all those cases where the symptoms of pain and alteration in the sensibility of parts precede those of ataxia, we find the columns of Burdach first affected with a systematic lesion, and, afterward, those of Goll. The investigations of Pierret and Charcot seem to demonstrate that the condition of sclerosis of the columns of Burdach usually begins in the lumbar enlargement, and tends to creep gradually upward toward the medulla oblongata, so that the entire length of the cord may become hardened and atrophied; while the same condition of the columns of Goll is usually found to coexist, but may be looked upon as a secondary result of the former.

Now, we have mentioned certain peculiar symptoms which point, when present, to some disease of the posterior columns of the spinal cord, among which come pain, hyperesthesia, numbness, anesthesia, and symptoms of incoördination (ataxia) when the disease is far advanced. We discover no motor symptoms, as the muscular power appears to be normal in all respects, except in coördinate movement; and "trophic changes" in tissues are produced less frequently than if the anterior portion of the cord were involved. It will help us to recognize this disease, if we will study a little more in detail each of these various manifestations of posterior spinal lesions.

In the first place, the pains of this type of sclerosis are peculiar. They do not follow the course of special nerve trunks, as do neuralgic pains, but are more localized. They are vagrant in character, since they affect innumerable spots in the region which is presided over by the nerves connected with the diseased portion of the cord; and so marked is this peculiarity that a patient who has long suffered with these pains can not well select any spot which has entirely escaped them. Again, the pains vary in their intensity, since they are more or less paroxysmal, and often show exacerbations due to atmospheric changes. These exacerbations may occur every few minutes for some hours, and may then disappear for

1 Trophic changes in connection with posterior sclerosis point often to a complicating peripheral neuritis.

days or weeks; the area covered by them may vary from that of a small point to that of your hand; and they may be referred to the skin alone, the muscles, the joints, the bones, or, in rare cases, to the viscera. These pains are usually of a sudden character, and extremely severe. They assume the character of stabbing, tearing, or shooting sensations, which often cause the patient to shriek in agony; while the skin over the circumscribed spot is rendered hyperæsthesic to slight pressure, although firm pressure often affords relief. The terms "fulgurating" and "terebrating" are often applied to these pains, from their sudden onset and their similarity to the effects of a passage of a strong electric current. In fact, the distinctive characteristics of the pain of sclerosis of the posterior columns of the spinal cord are so well defined that I seldom hesitate to predict the development of later ataxic symptoms from this guide alone. It is usually confined to the lower extremities (toes, foot, shin, calf, and thigh), but it sometimes affects the trunk and the upper extremity, and, in very rare cases, the head. It is to be differentiated from the pain of rheumatism or of a simple neuralgia, and, as it is the initial symptom of a serious and incurable disease, it should be recognized early.

Touching upon this point, Professor E. C. Seguin, in a late lecture, puts the diagnosis of this affection, with his accustomed clearness, as follows:

"The only two conditions in which pains somewhat resembling fulgurating pains occur, in my experience, are paralytic dementia and gout. In the former disease, slight fulgurating pains-smaller' pains, if I may be allowed the expressionare described by the patients; but, in many of these cases, autopsy shows that, besides the cerebral lesions proper to the disease, the posterior columns of the cord exhibit pathological alterations; so that these cases are, after all, quasi-tabetic. The sharp pains of gout are short, stabbing pains in the skin of various parts of the body, compared by the patients to the prick of a needle, cold or hot. There is no tendency to repetition of the pain in one spot for hours or days; the sen

THE PAINS OF LOCOMOTOR ATAXIA.

605

sations appear in various parts of the body, and are bearable.

"The differential diagnosis of fulgurating pains from the pains of neuralgia, strictly speaking, is very easy. In neuralgia the pain is in the course and distribution of one or two (single) nerve trunks and their branches; it may be paroxysmal, but does not assume the excessive irregularity of tabetic pains, viz., agony for a few hours, and freedom from pains for hours, days, or weeks. The hyperæsthesia, in fulgurating pains, is at the seat of pain. In neuralgia, we find regular tender points' along the nerve trunk, or where its branches become superficial. The lightest touch causes pain in the painful districts in tabes, while the tenderness of nerves in neuralgia is usually demonstrable only by firm, localized pressure. Further, true neuralgia is seldom bilateral, while it is the rule for fulgurating pains to appear on both sides of the median line-in both lower extremities, for example. A last important distinction is that neuralgia is relievable or curable, whereas fulgurating pains are practically incurable, and fully relieved only by morphia injections.

"The confusion so often made between 'rheumatism' and the first stage of sclerosis is even less pardonable. Of course, no practitioner would mistake fulgurating pains for articular rheumatism; the error is with respect to 'rheumatism,' so called, affecting muscular masses and aponeuroses. In these 'affections the pains are usually dull, nearly constant, and distinctly aggravated by movements. Pressure must be firmly made upon the parts to produce pain, whereas in fulgurating pains the condition is one of cutaneous hyperalgesia under a slight touch. Again, this rheumatic' condition is distinctly amenable to treatment (counter-irritants, etc.), whereas the pains of posterior spinal sclerosis are, in one sense, incurable."

Now, this symptom may exist for years without the development of marked anæsthesia or of ataxia, and often both the patient and the physician are inclined to speak of these pains as dependent upon some rheumatic diathesis, rather than as a precursor of an incurable affection. The peculiar