therefore of physiological potentiality, may occur in a myelitic
cicatrix. But the experiments of Kahler[92] and Homén[93] prove that
when a nerve-tract {816} is once destroyed within the spinal cord all
hope of restoring that tract in structure, and thus to restore its
functions, is at an end. Unlike the fibres of the peripheral nerves,
those of the spinal cord and brain do not seem capable of
regeneration.[94] If a restoration of function is to occur at all, it
must occur through other channels than those destroyed—in other words,
by vicarious action.
[Footnote 92: _Prager medizinische Wochenschrift_, 1884, No. 31.]
[Footnote 93: _Contribution expérimentale à la Pathologie et à
l'Anatomie pathologique de la moelle épinière_, Helsingfors, 1885,
abstracted in _Centralblatt für die medizinisches Wochenschriften_,
1886, No. 16.]
[Footnote 94: According to the first observer, this is probably due to
structural differences. The extramedullary fibres have a sheath and
annular constrictions which are absent in the intramedullary.]
In a large number of cases myelitis is a limited affection; that is,
its ravages remain confined to the area originally involved. But
occasionally the morbid process involves the next segments above or
below, extending with specially great rapidity through the anterior
gray horns. Exceptionally, the entire cord may thus become the site of
a generalized myelitis. There is one segment of the cord which may be
regarded as possessing an acquired vulnerability when a myelitic focus
is in its neighborhood, and that is the lower end. It seems that while
the results of a transverse myelitis in the middle dorsal cord may
remain stationary for ten or more years, those of a transverse
myelitis at the upper lumbar level do not; on the contrary, the entire
cord below the lesion appears to be doomed to undergo the same
degeneration by contiguity. This is the only occurrence which seems to
deserve the name of a descending myelitis: an ascending extension is
more frequently noted in other parts of the cord, but the frequency of
both the so-called ascending and descending types has been unduly
magnified by the inclusion of the secondary degenerations, which are
constant sequelæ of all complete destructive transverse lesions of the
cord, but which are rather passive phenomena, and probably influence
the clinical progress of the case but little, except under such
conditions as are potent in that chronic form of myelitis which
underlies tabes dorsalis.
CLINICAL HISTORY.—The symptoms of acute myelitis usually correspond to
those of any more or less completely transverse lesion of the cord,
and accordingly vary with the altitude of the upper level of the
lesion. In a general way, they may be stated as consisting of—
First, paralysis of movement in the parts supplied from the nerves
given off below the level of the lesion. The reason for this can be
easily recognized in those cases where the pyramid tract, which
conveys voluntary impulses centrifugally, is interrupted by the
softening.
Second, paralysis of sensation in the parts supplied by the same
nerves. This is equally explained by the pathological interruption of
the centripetal impressions normally conveyed brainward.
Third, alterations in the nutrition of the parts supplied by the
nerves arising in the affected level.
Fourth, abolition of those reflexes which are translated in the level
of the lesion.
Speaking crudely, then, the symptoms of a transverse myelitis fall
into two natural groups. The one which includes the first and second
categories enumerated are symptoms due to interruption of cerebral
functions; the other, which comprises the last two categories, being
due to abolition or perversion of spinal functions. There is a third
group comprising certain constitutional symptoms.
{817} Aside from those variations due to the distribution, extent, and
intensity of the lesion there are others which depend on the rapidity
of its invasion. There are three types in this respect—the
apoplectiform, the ordinary acute, and the subacute. The term
apoplectiform has been used in two different senses, one being
clinical, and referring to the rapidity of onset of the symptoms; the
other anatomical, and referring to the nature of the lesion. It is,
however, doubtful if a distinction in the latter sense is practically
valuable. The presence of a blood-clot in a myelitic focus is itself
secondary to the softening, and the intensity and rapidity of the
process must have shown itself in the development of the latter.[95]
The term ought, therefore, to be used in a clinical sense only.
[Footnote 95: I am able to recall but a single case in which, even
clinically speaking, a primary hemorrhage into the cord-substance was
plausible. In this instance a sudden arrest of menstruation had
occurred nearly simultaneously with a combined strain and exposure in
a young girl.]
The constitutional symptoms of acute myelitis—which, however, are
often absent—are its most distinctive features in one sense. Disorders
of motion and sensation and perversions of nutrition are signs common
to all destructive affections of the cord, whether of a traumatic,
neoplastic, or a chronic inflammatory character. But fever, headache,
and delirium,[96] associated with gastric and visceral disturbances of
acute development, are not found to be initial and intrinsic symptoms
with them as with acute myelitis. In their absence the mode of onset
is characteristic. A high degree of paralysis, motor or sensory, is
developed with a rapidity unequalled in any chronic affection of the
cord. Sometimes there is a prodromal period in which formication,
numbness, and disorders of movement are observed in the same part of
the body which are destined to become paralyzed at a later stage of
the malady. Within a few hours, days, or at most weeks, complete
paraplegia may become developed. The prodromal symptoms may include
any form of disturbed sensation. Lancinating pains, tingling, a
feeling of the limbs falling asleep, peculiar and indescribable
sensations attending the acts of micturition and defecation or of
placing the feet violently on the ground, are common. Occasionally
they are found in one limb only, although motor and sensory paralysis
may ultimately occupy the symmetrical member as completely as the one
first involved. In some cases it has been noted that the patient is
unable to lie down, or, if lying, to occupy the dorsal recumbent
position. This feature has been utilized to support the theory of an
initial congestion, which is supposed to be relieved or aggravated
according as the cord is kept elevated or depressed.
[Footnote 96: These symptoms are to be regarded as actual parts of the
myelitic symptoms only when they accompany the prodromal or initial
periods. The later complications, uræmia and septicæmia, the latter
arising from pyelitis, cystitis, or decubitus, often lead to
constitutional disturbance which is not due to the myelitis as such.]
In most cases of transverse myelitis, when the anterior cornua are
destructively involved, we possess in the electrical tests valuable
and unerring means of determining the altitude and extent of the
lesion. Whenever we find the atrophy of a paralyzed muscle accompanied
by qualitative electrical changes in myelitis, we must conclude that
the cell-group from which that muscle receives its nerve-supply is
destructively involved.[97] These changes are particularly well
demonstrable when the {818} cervical or lumbar enlargements are
affected. They are not as readily ascertainable in the case of a
transverse myelitis in the upper dorsal region, on account of the
situation of the muscles supplied by the upper dorsal nerves, and the
consequent difficulty of application of the necessary tests.
[Footnote 97: The proposition, originally, I believe, made by myself,
that there are distinct cell-groups in the spinal cord which are
constant with certain animal species, and correspond in relative
development to ventral, dorsal, and appendicular muscular groups
(“Architecture and Mechanism of the Brain,” _Journal of Nervous and
Mental Diseases_, April, 1880), appears to be confirmed in a general
way by the researches and cases of Edinger, Kahler-Pick,
Dejerine-Major, Genzmer, Von Monakow, Sahli, Prévost-David, F.
Schultze, Remak, and Parrot-Joffroy; for the knowledge of the first
and last of which I am indebted to the review of the subject by Starr
(“Localization of the Functions of the Spinal Cord,” _American Journal
of Neurology and Psychiatry_, August, 1883).]
The disturbance of the deep reflexes with very few exceptions affects
the same peripheries as are represented in the destroyed and impaired
gray nuclei. Thus, if the lower part of the lumbar enlargement be
affected, the reflexes of the Achilles tendon and the gluteal muscles
will disappear; if the upper lumbar enlargement, the knee-jerk
disappears.[98] Disease of the lower part of the cervical enlargement
is in like manner associated with absence of the wrist-tendon
reflexes, while the disappearance of the elbow-tendon reflex suggests
a higher involvement at the levels of the fifth and sixth cervical
nerve-roots.
[Footnote 98: The disappearance of the knee-jerk and similar reflexes
was originally supposed to be a phenomenon exclusively pertaining to
spinal disease and to a destructive lesion anywhere in the track of
the centripetal and centrifugal nerves connected with that segment of
the cord in which the reflex is supposed to be translated. But aside
from a number of physiological observations[99] which prove that
cerebral conditions may influence the intensity of the jerk, there are
pathological ones which show that it may be permanently abolished in
disease of the pons and cerebellum, and temporarily abolished or
diminished immediately after capsular and ventricular hemorrhage. The
associated symptoms in the former case, and the history of the onset
and total hemiplegia in the latter, serve to distinguish them from
destructive spinal lesions should the occasion for discriminating
between them ever arise; which is not likely.
[Footnote 99: S. Weir Mitchell and M. J. Lewis found that voluntary
effort increases the jerk at first, but if continued diminishes its
excursiveness (_The Medical News_, 1886, Feb. 13th and 20th).]
In complete transverse acute myelitis of the cervical region high
fever is a constant symptom. In unilateral myelitis of this region
flushing of the face and unilateral sweating are produced, together
with iridoplegia, sometimes preceded by dilatation, owing to initial
irritation and succeeding paralysis of the sympathetic branches
originating at this level of the cord.
Just as the disturbed reflexes and the belt sensations enable us to
distinguish at what levels of the cord the myelitis is situated, so
the distribution of the motor and sensory paralysis affords
corroborative evidence of such location and additional proof of its
extent and intensity.
Transverse myelitis at and above the level of origin of the phrenic
nerve is almost immediately fatal, through its interference with the
innervations required in respiration. In the upper part of the
cervical enlargement it produces complete paraplegia of motion and
sensation in the trunk and all four extremities. In the lowest part of
the cervical enlargement it produces paralysis of the same parts, but
the serratus magnus and scapular muscles escape. The nuclei of origin
of the muscles moving the upper extremity are situated so that those
which are farthest removed from the axis of the body when the arms are
extended are situated lowest in the cord. The sensory paralysis is
distributed in harmony with the motor paralysis; that is, when there
is paralysis of motion in the hand {819} and forearm the anæsthesia or
subjective numbness is also in the hand and forearm. The same
correspondence is not found in affections of the lumbar enlargement,
for anæsthesia of the gluteal region accompanies paralysis of the
crural muscles when the lesion is low down at the level of the lower
lumbar and upper sacral nerves. The distribution of the anæsthesia, in
other words, is not by segments of the limb, but by surfaces. The
gluteal, posterior femoral, gastrocnemial, and outer pedal surfaces
are affected together with the muscles moving the foot, while the
thigh and inner side of the leg and foot become anæsthetic, with
lesion of the upper part of the lumbar enlargement accompanying
paralysis of the quadriceps and deep muscles. It is not difficult to
understand this discrepancy when we bear in mind the different plan of
distribution followed by the brachial plexus as compared with the
lumbar and sacral plexuses. It is not, in my experience, found that
the anæsthesia affects that surface which covers the part moved by the
paralyzed muscle; which is characteristic of associated paralysis and
anæsthesia from cortical disease.
One of the most dreaded occurrences in acute myelitis is the malignant
bed-sore. The ordinary decubitus which results from the protracted
sojourn of the patient in bed, coupled with the prominence of his
trochanters and sacrum resulting from general or atrophic emaciation,
is also common, but is comparatively benign and easy to prevent or to
manage when established. The malignant bed-sore, on the other hand, is
a spontaneous occurrence, due to the same obscure but undeniable
trophic influences exerted for good by the normal and for evil by the
diseased nerve-centres, which play so large a part in the
symptomatology of tabes dorsalis. It cannot be avoided; it is not due
to pressure alone, or, as some have claimed, to the macerating
influence of the dribbling and decomposing urine. The development of
this lesion is exceedingly rapid, and it may be regarded as a sort of
local gangrene. The skin shows a livid color; vesicles appear, then
burst; the part becomes denuded; and within a few days a deep ulcer
with a dark border and base appears, discharging a sanious fluid. The
subsequent history is that of a rapid extension and destruction of the
neighboring tissues, even down to the bone, and if situated over the
sacrum opening into the spinal canal through the necrotic arches of
the sacral vertebra, thus leading either to general septicæmia or to
putrid infection of the spinal meningeal sac. Occasionally, gangrenous
spots coexist on other parts of the body, notably the lower
extremities, where neither pressure nor maceration can be accused of
playing a part, proving that the process is primarily due to the
spinal affection.
Acute central myelitis, as described by Dujardin-Beaumetz, Hayem,
Hallopeau, and Erb, usually runs its course very rapidly. Indeed, all
of these observers speak of it as the most violent and quickly fatal
variety of spinal inflammation. I have, however, seen one case with T.
A. McBride at the Presbyterian Hospital in which all the
characteristic symptoms of acute central myelitis were markedly
developed and present in their characteristic groupings, and yet the
patient had been suffering from progressing symptoms of myelitis for
one year and a half before that time.[100] {820} Usually, complete
anæsthesia and paralysis of the lower half of the body occur in this
form. But the most characteristic feature is a rapidly progressive
atrophy not only of the paralyzed muscles, but also of some which are
still partially under the dominion of the will. With this there is
extreme vesical and rectal trouble, the sphincters being paralyzed. As
a rule, the deep and superficial reflexes are destroyed—they are
always diminished—and trophic disturbances of a malignant type, such
as acute decubitus, joint-changes, and œdema, are common. The
paraplegia is characterized by the flaccid condition of the limbs; the
contractures and spastic symptoms found with other forms of myelitis
are entirely absent, and qualitative electrical changes, beginning
with disappearance of farado-muscular contractility, are found in the
atrophying muscles. There are marked constitutional symptoms with this
form; the tendency to an ascent of the process and successive
involvement of one segment after another of the gray matter is great,
and a fatal issue, as far as known, is inevitable.
[Footnote 100: At the time the patient had undergone such a profound
change in appearance that I failed to remember him, and it was only by
accident I learned that I had seen him in private consultation with
his family attendent, F. A. McGuire, a year previous. On the latter
occasion I had made the diagnosis of subacute myelitis chiefly limited
to the posterior columns; there were ataxia, both static and
locomotor, slight incontinence, belt sensation, and ocular symptoms,
with abolition of the deep reflexes in the lower limbs.]
DIAGNOSIS.—The principles governing the determination of the affected
region of the cord in acute myelitis are exactly the same as those
detailed in the later sections on Chronic Myelitis or Sclerosis, the
acuteness of the onset, and the relapses which sometimes occur, and
the predominance of irritative spasms—which, however, is an inconstant
criterion—serving to distinguish between the acute and chronic form of
spinal inflammation. In the present state of our knowledge it is
impossible to always differentiate between acute central myelitis and
syringo-myelus—a condition in which the formation of a periendymal
neoplasm, and its subsequent breaking down in the axis of the cord,
lead to the formation of a tubular cavity.[101] The neoplasm in this
instance is classified among the gliomatous new formations. The
symptoms depend, exactly as do those of myelitis, on the distribution
of the destructive lesion. In some cases the posterior cornua and
columns are chiefly involved, and extreme anæsthesia is found; in
others the anterior columns are affected, and the symptoms of a
poliomyelitis or an imperfect transverse myelitis may be
imitated.[102]
[Footnote 101: This cavity, unlike that of hydro-myelus, is not a
dilatation of the central canal, but, lying to one side of it, is
excavated in the cord-substance.]
[Footnote 102: Repeated fractures have been noted in cases marked by
profound analgesia. It is believed that they are not always due to
trophic changes, but may be the result of muscular action, exaggerated
on account of the patient's inability to gauge his efforts. Still, in
the majority of cases the presence of positive trophic disturbances of
the skin seems to indicate the probability of some textural change
facilitating the fracture.]
As a rule, the sensory disturbance in syringo-myelus is out of
proportion to the muscular atrophy developed; that is, it involves a
far more extensive province. It is usually of a peculiar character:
some forms of sensation are involved but slightly, or even escape, and
others may be nearly destroyed. Commonly, it is the pain and
temperature-sense which suffer most, while the cutaneous space and
pressure, as well as the muscular sense, are not materially disturbed.
These peculiarities are not commonly found in cases of myelitis, and
when present, and particularly when the paralytic or sensory
affections involve all four extremities {821} alike, they suggest the
existence of syringo-myelus. As yet we are unable to make more than a
probable diagnosis between the two diseases.
DURATION AND PROGNOSIS.—The duration of the disease varies. Cases of
the apoplectiform variety are mentioned, in which the process reached
its height in a few minutes, or where the patient, having retired in
good health the night before, awoke finding himself paralyzed in the
lower half of his body. Death may terminate such a case in a few days
or weeks. In another class of cases, complicated by serious
involvement of the bladder, the fatal termination is often
precipitated by putrid cystitis, pyelitis, or uræmic poisoning, and
even in cases which have passed the dangers of the early period in
safety these ominous complications may develop with the usual result
many years after the beginning of the illness. In a number of cases
the first period, that in which the morbid process becomes developed,
is followed by one of comparative quiescence, in which the paralyses
of sensation and motion then established remain stationary for months
and years. A number of authors, Erb, Leyden, Strümpell, and Ross,
speak of such a case as one in which chronic myelitis has followed an
acute myelitis. It seems improper to use the terms acute or chronic in
this way. As it is generally understood that the term acute applies to
myelitis in which disintegration of the nerve-elements predominates
over interstitial proliferation, and in which the secondary sclerosis
is rather like the cicatrix of an acute inflammation and necrosis, it
should not be confounded at any period, no matter how similar the
clinical signs may be, with a process which is essentially an
interstitial one from the start. If chronic amaurosis results from an
acute glaucoma, we do not change the latter designation to chronic
glaucoma.
In cases where the symptoms at the acme indicate rather an involvement
of the peripheral than the central paths of the cord, and in which an
incomplete motor and sensory paralysis develops, the patients often
regain a considerable amount of motor power and sensation, so that
they may reach a good age, suffering at most from a paresis of some
one muscle or muscular group, occasional bladder trouble, and pains.
It has been laid down as a rule that where paraplegia and other signs
remain stationary for years, there is no hope of even partial
recovery. The following remarkable and well-attested case proves that
this rule is not without exceptions:
Isidor K——, æt. forty-four years, worker in tobacco. After
over-exertion in the fall of the year 1879 he had numbness, tingling,
dorsal pain, and paresis rapidly developed, which induced him to
consult the physicians at the clinic of the University of the City of
New York. After some slight improvement a relapse occurred, and
several others followed, usually provoked by over-exertion, till he
became completely paraplegic. He was, according to his account,
several times exhibited to a medical class by William A. Hammond, and
remembers that this authority spoke of a possible ascent of the
affection and ensuing involvement of the arms. His bladder was at no
time seriously disturbed. For four years and three months he was
totally paraplegic; his lower extremities were without life; and for
the greater part of the time he could not move his toes. The limbs
were cold and pale, but underwent little atrophy. The only exercise
obtained during this time was in a roller carriage. His sexual power
was abolished throughout the whole {822} four years and over. Nothing
can be learned as to his reflexes in this period.[103] The paralysis
of sensation was as complete as that of motion, and the lower limbs
never perspired. The arms remained free. There was a dorsal belt
sensation.
[Footnote 103: Hammond has no notes of the case, having discontinued
the clinic, and Ludwig Weiss, the physician in charge, saw him only
occasionally in behalf of a benefit society.]