Système nerveux_) Charcot termed this, and one other form of disease
associated with muscular atrophy, amyotrophic, to distinguish them
from the myopathic forms. He considers amyotrophic lateral sclerosis
as deuteropathic, the nuclear atrophy being secondary to the lesion of
the white substance, and the progressive muscular atrophy of the type
described by Duchenne and Aran as a protopathic form of the
amyotrophies. Among the true myopathies he enumerates
pseudo-hypertrophic paralysis, Erb's juvenile form, Duchenne's
infantile form, certain mixed forms, and, without justification,
Leyden's hereditary forms (report by Marie et Guivron, _Progrès
médicale_, 1885, No. 10).]
MORBID ANATOMY.—In advanced cases of amyotrophic lateral sclerosis
there is found marked sclerotic degeneration of both the crossed and
the uncrossed pyramid tracts; atrophy of the cells of the anterior
horns; atrophy of some of the nuclei of the motor and mixed cranial
nerve, particularly the hypoglossal and spinal accessory; atrophy of
the anterior roots of the spinal and the roots of certain motor
cranial nerves; and, finally, atrophy of the voluntary muscles. The
greater part of the tract through which the voluntary impulse travels
after leaving the voluntary motor-fields of the cortex is therefore
continuously involved; and it would seem that there are cases
(Kahler-Pick's) where the entire motor system is affected, the morbid
process demarcating the course taken by the motor impulse through the
cerebro-spinal fibre-labyrinth from the cortical motor-field down to
the muscles.
The morbid process in the muscles consists of a narrowing of the
fibres, which subsequently lose their transverse striation and undergo
a granular disintegration. Sometimes a muscle disappears entirely;
usually the connective-tissue elements, including the interstitial
cellular and adipose tissue, undergo proliferation, so as to mask the
wasting of the muscles to some extent.
The morbid process in the nervous system is also a simple degenerative
process. The nerve-fibres and cells atrophy first, and the
connective-tissue proliferation which marks the sclerotic change of
the diseased area is a secondary process. There is still considerable
dispute among authorities as to which segment of the motor-conduits
the degeneration begins in. But from the great difference found in the
individual cases which {868} have become the subject of
patho-anatomical studies there can be little doubt that there is no
uniformity in this respect. In some cases the lesion is far advanced
in the lateral columns, while the anterior horn is but slightly
involved; in others the reverse is found. Sometimes the nuclei of the
motor cranial nerves are the chief foci of disease; at others they are
the least affected parts of the motor apparatus. As we shall see,
there are differences in the clinical picture corresponding to the
variations of the anatomical findings.
CLINICAL HISTORY.—In typical cases the first symptom is a tired
feeling in one arm or leg, usually the former; in dextral persons the
right arm, the one which is subject to the severest strain, is most
frequently the first to be affected. With the increase in this tired
feeling there develops actual loss of power; the muscles become
wasted, and the other arm becomes involved. Often it is observed that
the right leg suffers with the corresponding arm, but as a rule the
lower extremities do not become involved to any marked degree within
the first six months of the illness. It is then noted that a gait not
unlike that of spastic paralysis is noted, but with more loss of motor
power and less stiffness. There is, however, this noteworthy
difference between the affection of the lower and that of the upper
extremities: that atrophy and loss of power are more marked in the
latter, and spastic phenomena in the former. The knee-jerk and other
deep reflexes are greatly increased, and ankle-clonus is usually very
well marked. As with spastic paralysis, there are no visceral or
sensory disturbances. Unlike that affection, there are qualitative
changes in the electrical reaction of the muscles[105] in amyotrophic
lateral sclerosis. The degeneration reaction is found in the atrophied
divisions, and particularly in such groups as those of the thenar and
hypothenar eminence, which undergo complete atrophy at a comparatively
early period of the disease.
[Footnote 105: Moeli, Strümpell, Pick, and Mierzejewski describe cases
in which only quantitative changes were found. They were such in which
spastic phenomena preponderated at the time of the examination.]
Soon after the spastic and atrophic involvements of the lower
extremities, symptoms indicating the involvement of the cranial
nerve-nuclei are developed, usually after the disease has lasted a
year or so. Deglutition becomes difficult and speech indistinct, the
general picture of a glosso-labio-laryngeal paralysis being imitated.
The patient cannot pucker his lips, his lingual muscles undergo
atrophy, and fibrillary and fascicular twitches are noted in the
tongue and lips. But just as the atrophic affection of the muscles of
the arms and legs differs from that of progressive muscular atrophy in
the fact that the deep reflexes are exaggerated with amyotrophic
sclerosis, so in the bulbar symptoms of the latter it is found, unlike
the typical form of bulbar paralysis, that the jaw reflex is
increased.
The duration of the disease may be stated at about three years, death
usually occurring in consequence of the involvement of the cranial
nerves. There are cases recorded where the disease was almost
simultaneously developed in all four extremities and the tongue,
reaching a high degree within a year (Mierzejewski). It is generally
agreed that the reason contractures do not develop in typical cases of
this kind, although the lateral column is sclerosed and spastic
phenomena occur early in the disease, is the destruction of the
cell-groups in the anterior horn. The reflex arch {869} through which
a reflex contracture would be mediated is broken, or rather weakened,
in that part of its course which passes through these cells, and
therefore a contracture is as efficiently antagonized as it would be
if the posterior roots were divided. Still, in some cases a frozen
attitude of the lower extremities is very well marked (Vierordt,
Zacher). To reconcile these conflicting observations it has been
suggested that it may be regarded as a question of speed between the
progress of the pyramid-tract and the anterior-horn lesions. If the
former be much in advance of the latter, spastic phenomena will
preponderate and contractures be possible, to disappear with the
subsequent anterior-horn lesion. But if the latter precede and
preponderate, the spastic phenomena will be in the background and
contractures impossible. Indeed, Zacher[106] suggests that there may
be an ascending form in which the lesion of the pyramid tract is
secondary to the nuclear atrophy, corresponding to the typical class
of cases on which Charcot based his first description of the disease,
and a descending form in which the pyramid tract is first affected and
the nuclear cell-groups follow. Vierordt[107] and Kahler[108] express
similar opinions. The latter goes so far as to suggest that
progressive muscular atrophy, progressive glosso-labio-laryngeal
paralysis, and amyotrophic lateral sclerosis are really due to one and
the same kind of degenerative process, merely differing in location.
There is certainly, as he claims, a remarkably complete chain of
cases, beginning with such (1) in which spastic paralysis
preponderates, passing thence to (2) those in which some muscular
atrophy preponderates, then (3) those in which muscular atrophy is in
the foreground and the spastic phenomena are slight, and ending with
(4) the pure atrophies. A similar transition may be established on the
regional principle between pure glosso-labio-laryngeal paralysis and
amyotrophic lateral sclerosis, for there are cases of this affection
in which the oblongata symptoms preponderate throughout, and the focus
of the disease is formed there, just enough lesion being demonstrable
in the pyramid tract and the spinal gray matter to prove the family
relationship of what clinically appears as a spastic bulbar
paralysis.[109]
[Footnote 106: _Archiv für Psychiatrie_, xv. p. 416.]
[Footnote 107: _Ibid._, xiv. p. 397.]
[Footnote 108: _Zeitschrift für Heilkunde_, 1884, p. 109.]
[Footnote 109: Such a case is described by Freund in _Deutsches Archiv
für klinische Medizin_, xxxvii. p. 405.]
PROGNOSIS.—As far as the typical cases of this disease have been
studied, a fatal termination seems to be invariable. Seeligmüller
reports a few cases in which the progress appeared to become arrested,
but it is not clear that these were not in reality cases of some
juvenile form of muscular atrophy. Not only is the affection in adults
fatal, but it is so in a short period of time as compared with other
spinal disorders, and particularly with the related disorder spastic
paralysis. Few patients survive the third year of their illness; a
number do not live to that length.
The Combined Forms of Sclerosis.
A number of cases of chronic sclerotic disease of the cord have been
discovered and analyzed during the past decade, which, while they show
the regularity of distribution noted in posterior and lateral
scleroses, {870} differ from them in involving at once more than one
column of the spinal cord. Usually, it is the posterior column and the
posterior part of the lateral column which are affected. The symptoms
constitute a combination of those of tabes dorsalis and of spastic
paralysis. But this combination does not represent a mere addition of
symptoms; where the tendency of the two diseases conflicts, they
neutralize each other. Thus the tendency of lateral sclerosis
uncomplicated by posterior sclerosis is to increase the patellar jerk;
when posterior sclerosis complicates it, the jerk is annihilated. The
degeneration of the lateral column and the ensuing motor paresis in
like manner neutralize the ataxic character of the gait by limiting
its excursiveness.
The upper extremities are usually involved equally with the lower. In
the cases of Kahler-Pick considerable atrophy of the muscles
developed; in those of Prévost and Westphal this was not very
noticeable. In a few cases, where the posterior sclerosis did not
involve the lumbar part of the cord, spastic symptoms were noted in
the lower extremity. In the only case of combined sclerosis now under
my observation this peculiarity, noticed by Prévost, is well marked.
In one of Westphal's cases there was evident mimic ataxia. The few
cases of this affection observed show so many variations that it would
be at present premature to attempt sketching a common clinical type.
The majority of the subjects were affected between the twenty-fifth
and forty-fifth years.
ETIOLOGY.—Little is known of the causes of this disease. Usually
beginning insidiously, no special mode of origin can be determined.
Surface chilling has been assigned in a case by Erlitzky and Rybalkin,
and others are reported to have begun during pregnancy. One of
Westphal's cases developed in a lithographer who had been subject to
epileptoid fits.
DIAGNOSIS.—As yet we have no reliable criteria for distinguishing
between a combined sclerosis and certain forms of diffused sclerosis
during life. Ballet and Minor[110] found such a sclerosis diffusely
involving the posterior and lateral columns of the cord in a case
where they were justified from the symptoms in expecting a combined
fascicular sclerosis of these columns, and after a careful study of
all similar cases collated by them in consequence of this experience,
they came to the conclusion that a number of affections of different
origin, but eventually involving both columns, may impose on the
observer as combined fascicular sclerosis during life. Diffuse
meningo-myelitis is one of these affections, and is far from uncommon,
while true system or combined sclerosis is apparently a very rare
disease.
[Footnote 110: _Archives de Névrologie_, vii. p. 44.]
The Family Form of Tabes Dorsalis.
SYNONYMS.—Friedreich's disease, the Family form of locomotor ataxia,
Hereditary ataxia, Hereditary tabes.
Friedreich discovered a peculiar form of co-ordinating disturbance in
a number of children of the same family, which he brought into
relation with a lesion of the posterior columns, and which has been
since found by him and by subsequent observers to occur in other
cases, always {871} affecting several members of the same family, as
in the first case observed by him. The clinical and pathological
features, though resembling those of the tabes dorsalis of adults in
many respects, are distinct in others, and for this reason it is
generally assigned a separate place in classification.
ETIOLOGY.—The disorder is usually manifested in juvenile life, the age
of the affected subjects varying from the seventh to the twenty-fifth
year. The male sex preponderates in the statistics of the affection.
Some neuropathic vice can always be found in the patient's immediate
ancestry, and the limitation of the disease to families burdened by
such a diathesis is exemplified in the fact that the ninety individual
cases thus far accurately studied occurred in thirty-six
families.[111] The disease type of the ancestors of the patients is
usually different from that of the latter. Alcoholism in the father is
one of the commonest forms, but convulsions, hysteria, and insanity
are also frequent features of the family history. In a few cases tabes
dorsalis, properly so called, was present in the father. In others
there was consanguinity of the father and mother. In Musso's group the
parents had been brother and sister, and their mother had been a
melancholic dement. Three other grandchildren and six grandchildren by
the incestuous marriage developed the family form of tabes. In this
family the frequent experience of hereditary transmission was
verified—that the neurotic taint skipped the intermediate generations.
[Footnote 111: Raffaele Vizzioli, _Giornale di Neuropatologia_, 1885.]
CLINICAL HISTORY.—Usually the first symptom is ataxia of the lower
extremities; occasionally this is preceded by severe frontal headache
or by vague rheumatoid pains. The inco-ordination is very similar to
that of true tabes dorsalis, but swaying on closing the eyes is not
noticed early in the disease, as in the latter affection. The arms
soon become involved in the ataxia, but cutaneous sensibility and the
muscular sense remain either intact or nearly so—a fact utilized with
some success by Erb in polemicizing against the theory of Leyden that
the ataxia of tabes is due to imperfect sensation. Later in the
disease, usually after a few years, a peculiar speech-disturbance is
noticed, which resembles the scanning of disseminated sclerosis. It
depends on ataxia of the tongue and lips. This is usually associated
with nystagmus. About this time the patient develops a different set
of motor symptoms from those characterizing the onset of the disease;
contractures, paralysis, and atrophy are found in the affected
extremities; sometimes the patients cannot ascend a stair, owing to
their inability to lift the feet high enough. Pes equino-varus,
deformity of other joints and of the vertebral column, have been
observed[112] to result from the associated effects of paralysis and
contracture. At this stage some sensory disturbance may be developed,
formication having been observed toward the close of the history in a
number of cases. But the distribution of this disturbance is usually
different from that of tabes dorsalis, being more intense in the trunk
than in the extremities or evenly marked in the entire periphery.
[Footnote 112: H. E. Smith, _Boston Medical and Surgical Journal_,
1885, vol. cxiii. p. 361.]
COURSE AND PROGNOSIS.—The progress of this disease is slow. It has not
yet been known to be arrested by any therapeutical procedure. Death
rarely occurs directly from the disease by exhaustion; more commonly
life is cut short by some intercurrent affection. Unless this occurs
{872} the patients may survive the commencement of the illness from
eight to forty and more years.
MORBID ANATOMY.—The sclerosis which is found to be the constant lesion
underlying this disease corresponds in every character to a combined
sclerosis of the pyramid tracts and the posterior columns. Usually,
the crossed-pyramid tract is degenerated in its spinal course, and the
uncrossed in the cervical and dorsal part, which, in many subjects at
least, is its whole extent. The cerebral part of the pyramid tract is
not affected. The nerve-fibres found normally in the gray substance
are materially reduced, probably in dependence upon the atrophy of the
great nerve-tracts.
The lesion of the posterior columns resembles that of true tabes very
closely, particularly in the lumbar part of the cord. It is, however,
not probable that it commences in precisely the same distribution, and
if cases dying early in the disease be autopsied it will be
interesting to see whether the initial sclerosis occupies identical
fields—a contingency which is unlikely, owing to the profound
difference in the initial symptoms of true tabes and the family form.
It is claimed by Schultze that in addition to the pyramid and
posterior tracts the cerebellar tract—or, rather, a large part of the
periphery of the lateral column—may be sclerosed in this disease. In
this way, since the direct pyramid tract in the anterior, the greater
part of the border of the lateral, and the entire posterior column are
degenerated, the sclerosis resembles a marginal ring[113] in shape.
[Footnote 113: _Archiv für Psychiatrie_, xiv. p. 384.]
Anatomically, the sclerosis of the family form of tabes resembles that
form of combined sclerosis in which the lateral and posterior columns
are together affected. It is probably due to a defective development
of these tracts, rendering them liable to premature decrepitude or
increasing their vulnerability. The latter alternative is exemplified
in those cases where some acute disease of childhood, such as
scarlatina or measles, acted as an exciting cause.
DIAGNOSIS.—There are two affections some of whose leading symptoms are
so closely imitated by those of this disease that they may be
confounded with it on first sight. These are tabes dorsalis—of which
the family form is still regarded a variety, as the name indicates—and
disseminated sclerosis. In the gait the former, in the nystagmus and
scanning speech the latter, disorder is approximated. The distinction
from true tabes has already been dilated on. (See Tabes.) The fact
that relatives—usually the sisters and brothers—of the patient are
affected in the same way in their youth speaks in favor of the family
form. The deep reflexes are not abolished early, as in tabes, nor are
anæsthesias or paræsthesias early symptoms, as in the latter. The
speech-disturbance and nystagmus, which in most cases develop later in
the family form, serve to distinguish it from true tabes in the
advanced stage. It is at this period that the disease may resemble a
disseminated sclerosis. The hereditary or family character does not
aid us in making a discrimination here, as there is also a family form
of the latter disease. But the absence of intention tremor, which we
would assume to be present in a case of disseminated sclerosis of the
cerebral type, and of optic-nerve atrophy serves to distinguish the
two. Musso claims that the speech-disturbance is also different in
character. There certainly is more lingual ataxia in the {873} family
form of tabes, and less of typical scanning, but I am doubtful about
our ability to differentiate these characters in all cases. The
following table includes the main points of difference, clinically
considered, between the acquired and the family form of tabes:
| Tabes Dorsalis. | The Family Form.
---------------------+-----------------------+---------------------
Prodromata. | Marked and constant. | Absent or slight.
| |
Static ataxia | Early and constant. | Absent.
(Romberg symptom). | |
| |
Involvement of upper | Usually late. | Early.
extremities. | |
| |
Ataxia of tongue, | Absent or | Always developed.
eyes, and | unnoticeable. |
trunk-muscles. | |
| |
Paresis. | Rare. | Characteristic.
| |
Anæsthesia. | Present in some form. | Absent or slight.
| |
Paræsthesia. | Constant. | Rare.
| |
Sexual desire. | Becomes extinguished. | Remains unaffected.
| |
Deep reflexes. | Abolition usually | Abolition in course
| initial. | of disease.[114]
| |
Sphincters. | Involvement is | Involvement late, if
| characteristic and | at all.
| early. |
---------------------+-----------------------+---------------------
[Footnote 114: There are conflicting observations on this point.]
Disseminated Sclerosis.
SYNONYMS.—Multiple cerebro-spinal sclerosis (also spinal and cerebral
form), Insular cerebro-spinal sclerosis, Focal sclerosis, Multilocular
sclerosis; Herd-sklerose (Ger.); Sclerose en plaques disseminées,
Sclerose en plaques generalisées (French).
The occurrence of disseminated patches of gray degeneration in the
nervous axis was observed by Cruveilhier and Türck, but they regarded
the affection rather from the anatomical than the clinical standpoint,
and it was left for Frerichs to recognize its important position among
the chronic affections of the brain and spinal cord. The earlier
German investigators who followed him were cautious in generalization,
and it was not until Vulpian, Charcot, and their followers announced
the discovery of infallible diagnostic criteria that disseminated
sclerosis received that attention at the hands of the profession which
it merits. But the more thorough researches made during the last two
decades have shown that this announcement was premature. The best
authorities recognize the existence of a large number of cases in
which the supposed pathognomonic signs of disseminated sclerosis are
absent, notwithstanding the existence of characteristic lesions, and
thus the more cautious earlier investigators are justified in the
reserve they had maintained.
It is in perfect harmony with the irregular location of the disease
and the lack of any constant rule governing the distribution of the
sclerotic foci that there is no constant clinical picture by which its
existence can be accurately determined in all cases. The diagnosis of
tabes dorsalis, of spastic paralysis, of amyotrophic lateral
sclerosis, and of transverse myelitis rests on exact and constant
signs, but that of disseminated sclerosis does not. The dictum of
Charcot, that there is always intention tremor and nystagmus in
disseminated sclerosis, has long been overthrown. Well-determined
cases are on record by De Fleury and Westphal, and a number have been
observed by myself, where there was no {874} tremor or no increased
tremor with intended movement, and no nystagmus, nor any other of the
pathognomonic symptoms so considered by Charcot and his followers.
The morbid process of disseminated sclerosis consists in the
development of patches of sclerosed tissue, scattered apparently
without any regularity or rule through the brain and spinal cord. They
are the results of insidious inflammatory changes. The symptoms
marking their presence may include nearly every known focal and
general symptom studied by neurologists, varying with the number,
size, and distribution of the foci. Usually there is some disturbance
of motility, both ataxic and paretic; in the majority there is tremor,
which in a large proportion of cases is of a distinctive character,
and disturbance of the functions of the cranial nerves, amblyopia,
color-blindness, mental enfeeblement; and, above all, apoplectiform
seizures are frequent.