spastic, as it is as necessary in one as in the other to avoid as much
as possible the use of the affected muscles. A carpet-weaver, seen by
myself, was obliged to tie the knots in the warp on the distal
extremity of the second phalanx of the thumb, as the extensor secundi
internodii pollicis was partially paralyzed, so that he was unable to
keep the distal phalanx extended. This condition came on when he was a
compositor, and compelled him to change his trade. A condition of
spasm had preceded the paralysis.
The first dorsal interosseus muscle is frequently the seat of paresis;
this is readily discovered by measuring the power which the patient
has of lateral movement of the index finger and comparing it with that
of the sound hand.
III. Tremor (Tremulous Form).—Trembling or unsteadiness of the fingers
is occasionally seen, usually most marked in the fore finger when the
hand is at rest with the fingers slightly separated. In some cases
this may be sufficient to cause unsteadiness in work, prolonged work
and over-fatigue being most apt to produce it; as previously
mentioned, this is one of the premonitory symptoms of professional
muscular atrophy. {519} An oscillatory trembling, due to implication
of the supinators and pronator, is described by Cazenave,[40] which
interfered greatly with the act of writing. Tremor is of itself rarely
complained of by those affected with copodyscinesia, unless it becomes
sufficiently marked to cause interference with work.
[Footnote 40: “Observations de Tremblements oscillatoires de la Main
Droite,” _Gaz. méd. de Paris_, 1872, pp. 212-215.]
A peculiar form of nystagmus occasionally seen in miners may be
considered as belonging to this category. According to Nieden of
Bochum[41] it is caused by eye-strain in the defective illumination of
the mines, and consists not of a spasm, but of a defective
innervation, like the tremor of old persons. C. B. Taylor[42] of
Nottingham and Simeon Snell[43] also speak of this as a fatigue
disease.
[Footnote 41: “The Pathogenesis and Etiology of Nystagmus of Miners,”
_Am. Journ. Med. Sci._, Oct., 1881.]
[Footnote 42: Quoted by Poore, _loc. cit._]
[Footnote 43: “Miners' Nystagmus,” _Brit. Med. Journ._, vol. ii.,
1884, p. 121.]
IV. Pain, or Some Modification of Normal Sensation.—Every case of
copodyscinesia, without exception, has at one period or another of the
disease some modification of normal sensation in the hand or arm.
Usually the very first symptom that attracts the patient's attention
is a sense of fatigue or tire in the hand or arm, which at first
appears only after a considerable amount of work; if rest is taken
now, the part regains its normal condition, but if the work is
continued the sensation increases, and the amount of labor necessary
to cause the disability gradually grows less and less until any
attempt suffices to produce it. A painful sensation or a sense of heat
may be experienced in the shoulders or in the cervical or upper dorsal
spine at the time the foregoing symptoms are felt.
These symptoms are due to chronic fatigue in many instances, this
being an important factor in the causation of these troubles. An
expression frequently used by those affected is that the hand or arm
becomes lame; this sense of tire may be slight or may be of an intense
aching character, almost unendurable.
Should spasm supervene, then there will be a sense of tension and pain
in the rigid bellies of the muscles. When a subacute neuritis is
present, as frequently occurs, all the symptoms common to that
condition appear—viz. pain over the various nerve-trunks and at the
points of emergence of their branches, either spontaneous or only
solicited on pressure; areas of hyperæsthesia or anæsthesia; a sense
of itching or tingling or pricking in the arm or hand; or a sense of
numbness, causing the part to fall asleep.
As previously mentioned under Etiology, pain may be absent in some
cases of subacute neuritis. Occasionally, the distal phalanx of the
fore finger or thumb becomes exquisitely sensitive to pressure, and
there may be a burning or stinging pain under the nail, severe enough
to make the patient think local suppuration is about to take place.
Sensory disturbances in the region of the hand supplied by the radial
nerve are quite common, less so in the region supplied by the median,
and least of all in the ulnar distribution. This last having never
been seen by Poore, although, as pointed out by him, the muscles
supplied by the nerve are those most frequently implicated in this
disease when it affects scriveners, his explanation is that the deep
motor branches are {520} widely separated from the sensory branches of
the nerve, while this is not true of the radial.
One case of impaired sensation affecting the ulnar distribution, and
consisting of slight numbness of the palmar surfaces of the ring and
little fingers, has come under my observation. The patient was a young
woman affected with pianists' cramp, having as its foundation a
subacute neuritis of the musculo-spiral and ulnar nerves; the trouble
had lasted five years.
A curious form of pain, as of a bar thrust diagonally through the
hand, has been complained of; again, the arm, hand, or fingers may be
the seat of a subjective sensation of weight, so that one arm will
feel very much heavier than its fellow, or the hand may feel as heavy
as lead. A soreness and sense of tightness, as of a band around the
wrist, a throbbing and pulsation, or a tense feeling as if the skin
would burst when the hand was closed, have been noticed occasionally.
V. Vaso-motor and Trophic Disturbances.—Among the rarer symptoms seen
are vaso-motor and nutritional changes; these never occur alone, but
are accompanied by cramp and fatigue or by some evidence of
nerve-lesion.
When a patient with this symptom attempts to perform the task which
produces the disability, in addition to the fatigue, spasm, or pain
the veins on the back of the hand and fingers will be seen to slowly
enlarge; this may gradually increase until it extends over the whole
arm, the parts becoming more or less turgid with blood, the
temperature at the same time being somewhat increased. A marked
sensation of throbbing accompanies these symptoms.
Other parts more distant may become affected, the face becoming
flushed, palpitation of the heart and profuse perspiration, either
local or more or less general, ensuing, followed by exhaustion.
When there is a marked hyperæsthesia of the distal phalanges of the
fingers, there may be a glossy appearance of the skin, or the parts
may appear inflamed and as if about to suppurate, or there may be
chilblains. A rare symptom is change in the character of the nails,
which become brittle and crack off like shell, either spontaneously or
when an attempt is made to cut them.
GENERAL SYMPTOMS.—Besides the various symptoms above enumerated, there
may be others more general in character, such as intense headache and
great general nervousness, the emotional character being generally
well marked, as is shown by the disability being greatly increased
when the patient knows some one is watching and criticising. There may
be also vertigo and sleeplessness. When there is an associated spasm
of the analogous muscles of the other arm and hand, although there is
no apparent trouble in the arm which is being used, it shows that the
hitherto almost automatic act is losing some of its automatism: this,
although rare, is an important premonitory symptom.
A rare symptom, which, as far as my knowledge allows me to say, is
confined to telegraph operators, is an inability to mentally grasp the
proper number of dots and dashes composing certain Morse characters:
this usually coincides with the difficulty experienced in making those
characters after they have been thought of, and also makes it
difficult for them to recognize them by sound even when properly made
by another {521} person. The characters composed entirely of dots seem
to cause the most trouble in this way.
Electrical Reactions.—In those cases where spasm of one or more
muscles is a more or less marked symptom electrical examination shows,
both to the faradic and galvanic current, a quantitative increase in
the reaction, both in the nerves and muscles; with the galvanic
current the cathodal closing contraction is more marked than the
anodal closing contraction, as in health (KaSZ > AnSZ); only this
formula is most marked in the affected arm. When paresis is present
there will be a quantitative decrease in the reaction, the formula
still being KaSZ > AnSZ. In the same arm some muscles may show a
quantitative increase and others a quantitative decrease. Where there
is a neuritis present the electrical examination will show a
quantitative increase, but where the disease has advanced to
degeneration of the nerve the reaction of degeneration will be found,
and the formula will be AnSZ > KaSZ; there is, therefore, a
qualitative change, but this must be looked upon as rather uncommon in
this class of diseases.
Poore[44] is of the opinion that increased irritability shows an
early, and decreased irritability a late, stage of the same condition.
According to his tables, but very few of his 75 cases of impaired
writing-power showed this quantitative increase, while every case
showing the least evidence of cramp that has come under my observation
has shown it in one or more muscles; in a few cases the antagonistic
muscles showed a decrease. Increased sensitiveness to both currents is
sometimes noticed.
[Footnote 44: “Writers' Cramp and Impaired Writing-power,” by C. V.
Poore, M.D., _Medico-Chirurgical Trans._, vol. lxi, 1878.]
COURSE.—The course of the disability is slow and, unless appropriate
treatment is instituted, progressive, although at times there are
periods during which the symptoms ameliorate without assignable cause,
thus giving rise to false hopes. The usual history is that group after
group of muscles becomes implicated as these are in turn used to
relieve those first affected, the left arm, should this be used,
becoming disabled in the same manner as the right, and the unfortunate
sufferer is then compelled to give up his calling or else to lessen
very materially the amount of his labor.
DURATION.—As might be inferred from what has been written, those who
have suffered for years with this affection may expect it to continue
for the remainder of their days; but the later investigations upon
this subject give rise to much hope that in future the duration of
this troublesome complaint will be materially shortened when the
disease is recognized early and treatment instituted at the very first
symptom.
DIFFERENTIAL DIAGNOSIS.—Although many of the cases of copodyscinesia
are diagnosed with comparative ease, there are others which require
much study, as there are several disorders which are apt to mislead by
the similarity of symptoms.
Any affection of the finger-joints or of the muscles of the hand or
arm, or any disease of the nerves or of the spinal cord, from which
these nerves arise, or of the corresponding part of the brain, will
necessarily interfere more or less with the finer movements of the
hand, and yet all these, manifestly, cannot be considered cases of
this affection.
Where the symptoms are undoubtedly caused by over-use of a part, by
the constant repetition of the same muscular act, although the lesions
{522} may vary considerably in the different cases, they may be
classed with propriety under the above head; but there is a second
class which cannot be so considered, in which there has been a central
lesion which has arisen entirely independently of the occupation which
has become difficult to perform, and which disability is only one of
the many symptoms that have arisen on account of the aforesaid lesion:
these are the cases that it is important to differentiate from cases
of true copodyscinesia.
When a patient is suffering from a difficulty in performing a fine act
of co-ordination where previously there had been no trouble, much
information as to the cause may be gained by examining critically the
method in which that act is attempted to be carried out; thus, if the
patient has a difficulty in writing, his method of holding the pen and
his style of writing may throw some light upon the diagnosis; if he
holds his pen too firmly or if the down strokes are too heavy, or the
writing gradually grows smaller and smaller toward the end of the
line, there is a spasm of the flexor muscles; if, on the contrary, the
down strokes are imperfectly made or the thumb rises upon the holder,
or one finger shows a tendency to straighten itself, the extensors are
at fault. Each muscle should then be examined. By asking the patient
to make the different movements possible with the fingers and hand of
the affected side, and comparing them with those of the sound side, a
feebleness of one or more muscles may be detected. The offending
muscle may also be detected by electrical examination—by its reacting
more or less strongly than its fellow on the other side to the faradic
current or showing a quantitative change to the galvanic current.
By stripping the patient to the waist, or at least the arms, and
making a careful examination, atrophy or local lesions may be detected
that will aid in clearing up the diagnosis.
In telegraphers the mode of manipulating the key should be noted if
possible, and the faults made in the different Morse characters
studied; this will show as much in this form of the trouble as the
mode of writing does in scriveners' palsy.
The condition described by Mitchell[45] as post-paralytic chorea may
easily be mistaken for these affections, especially where the cerebral
lesion was coincident with much manual work (as writing or
telegraphing), and was so slight in extent that the paralysis was
transient and overlooked, the choreoid movements appearing later, and
affecting, as they may do, only the hand. Of this condition Mitchell
states “that it may exist in all degrees, with partial loss of power
and with full normal strength—that it may consist in mere awkwardness,
or exist to the degree of causing involuntary choreoid movements of
the parts.”
[Footnote 45: “Post-paralytic Chorea,” by S. Weir Mitchell, _Am.
Journ. Med. Sci._, Oct., 1874.]
The diagnosis can, in most cases, be satisfactorily arrived at by
careful consideration of the history of the case, the mode of onset,
the presence of some other signs of cerebral lesion, and the
examination of the heart and of the urine.
Some cases of paresis of the arm or hand from lesions of slight extent
affecting the arm-centres in the brain (minute emboli, disease of the
finer vessels, etc.) might possibly be mistaken for the paretic form
of copodyscinesia. Two cases[46] will illustrate this point:
{523} Case I.—Mr. G.——, æt. 58, dentist. A great writer, although
writing was always a difficult task and soon fatigued him. One day,
after excessive writing the day previous, he awoke with a loss of
power to write from an inability to properly co-ordinate his muscles;
his hand was not unsteady, motion was apparently unimpaired, and his
power good, but after laboring for ten or fifteen minutes he would
drop the pen. He was treated for writers' paralysis, and gradually
improved. One year later he was seized with aphasia and entire loss of
power in the right arm and leg. His further history is that of right
hemiplegia, and not interesting in this connection.
Case II.—Mr. W——, civil engineer, æt. 54. Until July, 1881, he
considered himself a healthy man, although very excitable; he was then
engaged in calculating and writing almost steadily for one week, which
exhausted him exceedingly; following this, he was engaged in an
abstruse calculation lasting another week, and at the end of this
period he awoke to find himself powerless to extend or flex his wrist,
and, to use his expression, his thumb would gravitate into his palm.
The movements of the shoulder and arm were comparatively unimpaired,
and with the exception of occasional dimness of vision of the right
eye there was no other symptom noticed. In one week he considered
himself well again. In July, one year later, after again passing
through a period of exceedingly hard work, he awoke to find that he
had lost sensation on the right side and had some difficulty in
articulating (muscular). Although thus warned, he worked steadily for
twelve hours the next day, in consequence of which he completely broke
down. After this he would occasionally write down a wrong word or put
down a wrong figure in calculating, etc. One month later he had a
transient attack of loss of power in right leg and other signs of
partial right hemiplegia, which was in all probability due to an
embolus, as there was a marked aortic systolic murmur.
[Footnote 46: From S. Weir Mitchell's notebooks.]
The point brought forward by Axenfield[47] that the paralysis in brain
lesions manifests itself equally in all movements of the fingers,
while in writers' cramp, etc. there is integrity of all movements
except those necessary for the special act, cannot be accepted as
diagnostic.
[Footnote 47: _Des Névroses_, par le Docteur Axenfield, Paris, 1864,
p. 389.]
Progressive muscular atrophy, as previously mentioned, bears a close
resemblance to professional muscular atrophy (Onimus), which may be
considered one of the forms of copodyscinesia. The resemblance,
together with the few points of difference, may be best seen in the
form of a table, thus:
PROGRESSIVE MUSCULAR ATROPHY. | PROFESSIONAL MUSCULAR ATROPHY.
|
1. Heredity in 24.63 per cent. | 1. Heredity not marked.
(Roberts). |
|
2. Affects adult males | 2. Affects adult males
principally. | principally.
|
3. Frequently follows exhausting | 3. Always follows exhausting
muscular activity. | muscular activity.
|
4. Atrophy a cardinal symptom. | 4. Atrophy a cardinal symptom.
|
5. When it affects the upper | 5. The muscles first affected are
extremities, the interossei and | generally the largest ones,
the thenar and hypothenar | particularly those in the
eminences are the first | neighborhood of the
affected. (Eulenburg says in his | shoulder-joint. The muscles of
experience the first dorsal | the hand may be affected first.
interosseus is always first |
attacked, and the others later.) |
|
6. Fibrillary twitchings | 6. Fibrillary twitchings
frequent. | frequent.
| {524}
7. Premonitory pains rare. | 7. Pains and cramps at the onset
| in the affected parts a
| distinctive sign.
|
8. Diminution of electrical | 8. (?).
reactions to both faradism and |
galvanism. Reaction of |
degeneration occasionally a late |
symptom. |
|
9. Prognosis generally | 9. Rapid amendment under rest and
unfavorable: as regards perfect | the use of constant and
restoration of muscles, almost | continuous electric currents.
hopeless. |
The ordinary course of symptoms in this disease is not always followed
out, and occasionally the resemblance of the initiatory symptoms to
one of the forms of copodyscinesia is great; the following is a case
in point:
W. F. G——, æt. 34, clerk, at one time an excessive smoker and a steady
writer. In the autumn of 1883 he noticed a numbness on the ulnar side
of the tip of the right index finger and on the radial side of the
middle third of the right middle finger, at about the points touched
by the pen-holder, which he held between these two fingers; this was
soon accompanied by a hyperæsthesia to light touches, and the two
together seriously interfered with pen-prehension; he then changed the
pen to the left hand, and soon noticed a numbness on corresponding
points on the left fingers. Any sudden extension of the right arm
would cause a thrill to shoot down into the fingers. Weakness of the
right opponens pollicis was present at the same time. These symptoms
caused the first physician consulted to make a diagnosis of writers'
palsy, but the later manifestations of the disease, six weeks
subsequently, soon showed its true character: these were marked
atrophy of the external portion of the thenar eminence (opponens
pollicis) and weakness and partial atrophy, and finally total loss of
power, of the anterior group of muscles of right leg (tibialis
anticus, extensor proprius pollicis, and extensor longus digitorum);
numbness and hyperæsthesia, as in the hand, appeared over instep.
Fibrillary twitchings were absent. The affected muscles did not
respond to the faradic current, while to the galvanic current there
was a quantitative lessening, the reaction still being normal in
kind—viz. KaSZ > AnSZ.
Paralysis agitans and multiple sclerosis both interfere with writing
on account of the tremor of the muscles; the latter disease markedly
so, as voluntary effort increases the trembling.
According to Sigerson,[48] the flexors are the least affected in the
former disease, and the extensors most so, especially the interossei,
which are the earliest involved; the down strokes of the writing will
therefore be made with comparative firmness, while the up strokes will
show the tremor.[49]
[Footnote 48: _Lectures on the Diseases of the Nervous System_, by J.
M. Charcot, trans. Philada., 1879, foot-note by Sigerson, p. 113.]
[Footnote 49: _Ibid._, p. 112.]
The writing in multiple sclerosis is much more wavy and irregular,
although the same tendency to firmness in the down strokes may still
be seen.[50]
[Footnote 50: _Ibid._, foot-note by Bourneville, pp. 153, 154.]
Both these diseases, when well pronounced, should occasion no trouble
in diagnosis, but there are cases where the symptoms are not typical,
and where the sclerotic change is slight in amount and principally
limited to the arm-centres in the cord, or at least to the anterior
columns, the symptoms being confined to the finer movements of
co-ordination of the hand and arm, and necessarily interfering with
such occupations as writing {525} much more than with those which only
necessitate coarser movements. The following cases illustrate this
point:
Case I.—J. S——, æt. 67, male. Two relatives had paralysis agitans (?).
Previous health good; present trouble began nine years ago. Tremor
first noticed in writing, and only then, but later any voluntary
effort of right arm was accompanied by a fine tremor, which became
particularly noticeable when the arm was semiflexed. This is now equal
in both arms. When patient writes slowly and with great attention to
each movement, he can write fairly for a short time; but if he
attempts to write quickly, there is a marked tremor which renders the
letters sometimes almost illegible. The up strokes show the most
tremor. There is no festination, no change in voice, no loss of power
over the sphincters, and no loss of reflexes; the reaction to the
galvanic current is normal.
Case II.—W. H——, æt. 58, male. For fifty years the patient has been a
hard writer, first as an editor and later as a cashier. In 1882 he
noticed difficulty in raising arm to put away papers in pigeon-holes
above his head; this movement caused pain in shoulder and arm. Shortly
after this he found that his hand became tremulous when he attempted
to write, and later any voluntary effort was sufficient to cause the
tremor. There has been no cramp. The grip of both hands is good, nor
is there any wasting of the muscles. Standing with eyes closed causes
no swaying, although there are occasional vertiginous attacks. While
walking he has noticed that the right arm does not swing with its
usual freedom. No ataxic pains are present. Reflexes of right arm and
shoulder are very much exaggerated; there are no changes in nutrition
or sensation. Galvanic reaction normal and alike in both arms. The
urine is non-albuminous.
The following case is in all probability one of diffused sclerotic
changes in the right lateral half of the cord, where the disease has
apparently ceased advancing: