With the Authors' Compliments. 
('Reprinted from the Cincinnati Lancet* Clinic, 
May30, i8g6. 
THE “SINUSOIDAL” CURRENT IN ELECTRO- 
THERAPY. 
BY 
F. W. LANGDON, M.D., 
CLINICAL PROFESSOR OF NERVOUS DISEASES AT MIAMI MEDiCAL COLLEGE ; NEUROLOGIST TO THE 
CINCINNATI HOSPITAL AND TO THE OPHTHALMIC HOSPITAL OF CINCINNATI 
AND 
W. EDWARDS SCHENCK, M.D., 
ASSISTANT AT THE NEUROLOGICAL CLINIC, MIAMI MEDICAL COLLEGE. 
(Read before the Academy of Medicine of Cincinnati, 
May 18, i8g6. 1lieprinted jrom the Cincinnati Lancet= Clinic, 
May 30, i8g6. 
THE “SINUSOIDAL” CURRENT IN ELECTRO- 
THERAPY. 
BY 
F. W. LANGDON, M.D., 
CLINICAL PROFESSOR OF NERVOUS DISEASES AT MIAMI MEDICAL COLLEGE ; NEUROLOGIST TO THE 
CINCINNATI HOSPITAL AND TO THE OPHTHALMIC HOSPITAL OF CINCINNATI; 
AND 
W. EDWARDS SCHENCK, M.D., 
ASSISTANT AT THE NEUROLOGICAL CLINIC, MIAMI MEDICAL COLLEGE. 
(Read before the Academy of Medicine of Cincinnati, 
May 18, i8g6. THE “ SINUSOIDAL ” CURRENT IN ELECTRO- 
THERAPY.* 
BY 
F. W. LANGDON, M.D., 
CLINICAL PROFESSOR OK NERVOUS DISEASES AT MIAMI MEDICAL COLLEGE, NEUROLOGIST TO THE CINCINNATI 
HOSPITAL AND TO THE OPHTHALMIC HOSPITAL OF CINCINNATI; 
AND 
W. EDWARDS SCIIENCK, M.D., 
ASSISTANT AT THE NEUROLOGICAL CLINIC, MIAMI MEDICAL COLLEGE. 
While all forms of electricity are 
identical in their ultimate nature, so far 
as we know, they may differ widely 
in their physiological and therapeutic 
effects, as is evident from the familiar 
differences in results obtained with the 
galvanic and faradic “ currents,” both 
as diagnostic and therapeutic agents. 
That the view once held, that the results 
observed from electrical treatment were 
altogether due to a “ psychic ” or “ sug- 
gestive” influence, is now no longer 
tenable in many cases, is evident when 
we consider that the form of current 
influences materially the result, and 
this in patients who do not know one 
current from another. Hence it is evi- 
dent that the differences noted in these 
cases at least are positive differences, 
due to the form in which the electricity 
is administered. 
We see an analogy, physiologically, 
in the differing effects of the two forms 
of phosphorus, and in the varying action 
of the various alkaloids which have the 
opium plant for their common source. 
Electrically, the now famous Roentgen 
rays afford another instance of the vary- 
ing effects derivable from one agent by 
changing its conditions of production 
and the relations of its application. 
The term “ current,” while a mis- 
nomer, is so firmly ingrained into our 
nomenclature as to be not easily dis- 
lodged, even if we possessed a more 
satisfactory name, which we do not. It 
is used here, therefore, in the conven- 
tional sense, as a general term for the 
varying phenomena due to the action of 
electro-motive force (“ E. M. F.”). 
The “wave symbol” is used as a 
convenient means of expressing graphi- 
cally one of the differences between 
“ currents.” The instrument known as 
the electrograph is used to register these 
“ waves,” in the same manner as similar 
instruments register for the physiologist 
the heart and respiratory movements, 
the pulse waves, etc. * 
Thus differences in the “ wave 
type ” of E. M. F. give rise to the fol- 
lowing forms of currents recognized by 
electricians.1 
Pulsating 
Intermittent. 
Non-in termittent. 
E. M. F. 
Continuous 
Steady. 
Alternating 
Symmetrical 
Dissymmetrical. 
f Sinusoidal. 
[ Non-sinusoidal. 
The “galvanic” current, as com- 
monly used in medicine, is a “ continu- 
ous steady” (i.e., direct) current (Fig. 
1). This is its form when produced by 
a battery; when derived from a dynamo 
it presents a finely undulating non-inter - 
mittent wave. The “ primary faradic” 
current presents an alternating dissym- 
metrical intermittent wave (Fig. a), 
with abrupt lines of ascent and descent; 
the “ secondary faradic” an alternating 
dissymmetrical intermittent wave, with 
1 Houston and Kennedy: “Electricity in 
Electro-Therapeutics.” New York: W. J. 
Johnston Co., 1896. 
* Read before the Academy of Medicine of Cincinnati, May 18, 1896. 628 
THE “SINUSOIDAL" CURRENT IN ELECTRO-THERAPY. 
Fig. 1.—“ Continuous steady ” line of flow of “ direct ” galvanic 
current. 
Fig. 2.—“Alternating dissymmetrical wave of pri- 
mary farad’c current. 
Fig. 3.—Alternating dissymmetrical intermittent wave of secon- 
dary faradic current. 
less abrupt lines of ascent and descent 
(Fig. 3). 
The “ combined” galvanic and fara- 
dic current (of DeWatteville) is the 
wave of the primary faradic to which 
is added “magnitude” (quantity—am- 
pereage) by the addition of the “ con- 
tinuous steady” (direct galvanic) cur- 
rent, which also eliminates the alterna- 
tions and dissymmetry. Hence it is 
described as a “ pulsating intermittent” 
wave (Fig. 4). 
The “ static breeze,” “ static spark ” 
and other forms of frictional electricity 
in common medical use are pulsating 
non-intermittent currents of high inten- 
sity and extremely rapid pulsation, but 
possess the disadvantage of variability 
in wave form (dissymmetry) (Fig. 5), 
and are not controllable as to frequency 
in a certain and convenient manner. 
Their uncertainty of action in damp 
weather is another drawback in prac- 
tice. 
The above mentioned are the cur- 
rents heretofore at the disposal of the 
profession for diagnostic and therapeutic 
purposes. 
The “ sinusoidal” current, the sub- 
ject of the present paper, presents an 
“ alternating symmetrical” wave of the 
form shown in Fig. 6. It is said to 
have been discovered by d’Arsonval, of 
Paris, about the year 1892. 
The accessible literature of the sinu- 
soidal current is as yet very meagre. 
D’Arsonval’s communications were pub- 
lished in the Archives de Physiologic, 
1888 to 1893. Kellogg makes some 
reference to the subject in the “ Inter- THE "SINUSOIDAL". CURRENT IN ELECTRO THERAPT. 
629 
F10. 4.—Direct pulsating intermittent wave of combined galvanic and 
primary faradic currents (“ DeWatteville’s current”). Frequency 
attainable with ordinary spring vibrator = 150 to 300 per second. 
Fig. 5.—Direct pulsating non-intermittent wave of “ static ” current. 
Fig. 6.—Alternating symmetrical sinusoidal wave produced by the Kennedy 
apparatus running at frequency of 480 alternations per second. Rate 
may be increased to 1920 per second. 
national System of Electro-Therapeu- 
tics.” 
The so-called “ Tesla” current, with 
which such surprising effects are ob- 
tained, seems to be a sinusoidal current 
of unusually high frequency. 
Various firms have placed on the 
market apparatuses devised for the pur- 
pose of producing the sinusoidal cur- 
rent. The only one of these with which 
I am familiar is the one here shown, 
which was constructed for me by the 
Edison Company, of Orange, N. J. It 
consists (as shown in Fig. 7) of an 
alternator, composed of twelve primary 
and secondary coils, mounted in circu- 
lar form so as to surround the dentated 
revolving armature, which is so pro- 
portioned as to produce the symmetri- 
cal sinusoidal waves required. Twenty- 
four alternations are produced at each 
revolution of the armature. 
These revolutions are produced by 
an electric motor of one-twelfth horse 
power, the speed of which is controll- 
able within given limits, by means of 
lamp rheostats. By varying the speed 
of the motor the frequency of alterna- 
tions, and consequently of the sinusoidal 
“ waves,” may be varied from 480 per 
second, the lowest, increasing by mul- 
tiples of this amount to 1,920per second, 
the highest. The current admitted to 
the primary coils is controlled also by 
four lamp rheostats, so as to be capable 
of variation between volts and mul- 
tiples thereof, up to no volts. As the 
“ sinusoidal secondary current” so pro- 
duced passes from the alternator to the 
binding posts, to be there transferred to 630 
THE “SINUSOIDAL” CURRENT IN ELECTR OTHER A P T. 
the patient, its intensity is regulated by 
a shunt water-rheostat (the “ Bailey”). 
The entire apparatus is conveniently 
operated by the no-volt continuous 
street current when available. When 
mounted for an alternating current a 
different motor and a battery to excite 
the alternator are required. 
The application is as simple as any 
other form of electrical treatment, and 
requires the same variety of electrodes, 
care as to gradual increase of current, 
etc. 
The physiological peculiarities of 
the sinusoidal current may be briefly 
stated as follows: 
1. The absence of pain, as compared 
with the faradic and galvanic currents 
of equal effect on muscular contraction. 
The more rapid the alternations (with 
this apparatus) the less the sensation, 
other things being equal. While this 
is not clearly explicable on electrical 
grounds, it would seem to the writer to 
be due to inability of the sensory nerves 
to respond to impressions of such high 
frequency. In other words, what little 
we know of the transmission of sensory 
impulses points to the probability that 
they are connected in some way with 
inter-molecular vibrations in the nerve 
elements, which vibrations have a limit 
varying with the previous education of 
the nerve substance. The rapidity of 
the alternations probably exceeds this 
limit, hence the failure of the sensory 
nerves to transmit and register as pain 
the alternating waves of such enormous 
frequency. 
A similar failure of appreciation is 
seen in the “ Galton whistle” test, the 
highest pitched notes of which are in- 
audible to the human ear while heard 
readily by some animals. 
2. The production of muscular con- 
tractions when faradism fails, i.e., in 
nerve degenerations following polio- 
myelitis, etc. The lower frequencies 
(480 per second) are better adapted to 
produce muscular contractions. In this 
feature it resembles the galvanic or 
direct current, with the advantage of 
absence of pain. 
3. The penetrating power of the cur- 
rent, which is probably superior to that 
of any other alternating current, and far 
exceeds that of the ordinary faradic coil 
and the “ static” currents. 
By reason of this great penetration 
its nutritional value is claimed to be 
great, and capable of being exerted on 
deep-seated organs. Hence in motor 
insufficiency of the stomach, chronic 
constipation due to bowel atony and 
relaxed abdominal walls its influence is 
particularly serviceable. The higher fre- 
quencies are best adapted to this end. 
As a consequence of this greater 
penetrating power also, this current is 
especially indicated where “general 
electrization,” either by faradism or 
galvanism, has heretofore been used. 
Here the higher frequencies (960,1,440, 
1,920 per second) are best used, since 
they are attended with less muscular 
contraction and the voltage may be 
higher. 
4. In the hyperesthesias of so-called 
“ hysterical ” or functional nature, the 
sinusoidal current finds a field of useful- 
ness peculiarly its own, not only because 
it is better borne by the hyper-sensitive 
structures, but also by reason of its ex- 
cellent effects on nutrition. It is hardly 
necessary to say that electricity alone 
is not a remedy for malnutrition, or a 
nutrient in any sense. Whatever good 
effects it may have are doubtless due to 
the promotion of metabolism and assimi- 
lation. He who attempts to build up a 
patient on tonics of any kind, without 
a correct dietary and hygiene, will find 
electricity as great a disappointment as 
any other treatment. 
The following brief abstracts are 
selected from a large number of cases 
treated by us with the sinusoidal cur- 
rent here referred to, in order to illus- 
trate its range of action. No attempt 
is made to select especially favorable 
results, but failures are recorded in 
rather greater proportion than they 
actually bore to the total number of 
cases treated. 
ORGANIC DISEASES. 
Locomotor Ataxia.—This disease has 
always been considered peculiarly hope- 
less as regards cure or the material miti- 
gation of its chief processes, and is con- 
sequently the favorite example held up 
by the pessimistic therapeutist to illus- THE “SINUSOIDATT CURRENT IN ELECTRO-THERARr. 
631 
Fig. 7.—Kennelly Sinusoidal Apparatus, made by the Edison 
Manufacturing Company. 
trate the powerlessness of remedies to 
favorably influence an organic nervous 
disease. Amongst the chief symptoms 
which annoy the patient and make his 
very existence miserable are (i) the 
“ lightning pains;” (2) the ataxic gait; 
both of which are the expression of de- 
generative changes in the peripheral 
intra-muscular nerve fibres. For the 
shooting pains the continuous adminis- 
tration of opiates and coal-tar analgesics 
is, to say the least, objectionable; and, 
even though the pains are thus made 
more bearable, the ataxia is unaffected. 
The sinusoidal current is the one 
satisfactory means known to the writer 
which is capable of absolutely removing 
the “ lightning pains” and at the same 
time materially benefiting the ataxia. 
To do the latter it should, of course, be 
used early, while some fibres are yet 
undegenerated. If the results heretofore 
obtained are verified by a larger and 
wider experience, it would appear prob- 
able that we have in this current a most 
desirable agent in the treatment of tabes. 
Whether the improved function is due 
to permanent better nutrition in the 
peripheral neuron or not, the cases ob- 
served are too few and the time too 
short to state positively. It appears to 
the writer probable that if treated at an 
early stage the progress of the disease 
may be materially slowed and the com- 
fort of the patient vastly increased. 
In this connection attention may be 
called to the chloride of aluminium as a 
remedy for the pains where, for any 
reason, the patient cannot have the 
benefit of electrical treatment. This 
remedy, to which attention was first 
called by Dr. Gowers, who introduced 
it to the profession for this purpose 
rather more than a year ago, we have 
found extremely serviceable in many 
cases. It is administered in doses of 
from two to four grains, dissolved in 
dialled water, three times a day. 632 
THE “SINUSOIDAL” CURRENT IN ELECTRO- THERAPT. 
On theoretical grounds we have 
thought it advisable, in the electrical 
treatment of tabes, to apply one broad 
electrode at the nape of the neck, the 
other over the painful areas. For the 
ataxia, a foot-plate is the best form for 
the lower pole and a broad neck elec- 
trode for the upper. The anatomical 
and pathological reasons for the selec- 
tion of the above localities are obvious, 
as the neurons affected in locomotor 
ataxia have their bodies (the so called 
cells) in the posterior root ganglia of 
the cord, while their axis-cylinders 
(axons), bifurcating, have one extrem- 
ity in the medulla, the other at the peri- 
phery. The old idea that the essential 
pathology of locomotor ataxia was a 
“ sclerosis” of the posterior columns of 
the cord is no longer tenable in the 
light of recent investigations. 
The disease is now considered pri- 
marily a degeneration of neurons, prob- 
ably beginning at the axis-cylinder end- 
ings. The “sclerosis” is a secondary 
result of the disappearance of the nerve 
structures—in short, nature’s way of fill- 
ing that much-abhorred vacuum. Hence 
the time to treat the disease is before the 
degeneration is complete. To do this 
early diagnosis is essential. 
The well-established pathological 
law that the portion of the neuron 
which first suffers in degenerative 
disease is that farthest from the (trophic) 
neuron-body, would furnish a rational 
indication for the selection of the locali- 
ties noted, since it is the degenerative 
process we hope to retard or arrest by 
improvement in circulation and func- 
tional activity. Another good reason 
for the selection of these localities is the 
fact that in the early stages of the 
disease some neurons are probably un- 
affected, and we may hope, by improv- 
ing the powers of assimilation and 
nutrition, to influence favorably their 
function, a “training” process which 
may be aided by the well-known one of 
having the patient practice co-ordination 
by walking a chalk line, practicing 
manual movements, etc. 
Case I.—Mr. A., forty-one, manu- 
facturer. Referred by Dr. F. B. Cross. 
Married, two healthy children. He- 
redity good. Chancre twenty years ago. 
No history of secondary symptoms. 
Lightning pains very severe for a year 
past; Argyle - Robertson pupil; lost 
knee-jerks, girdle anesthesia, seventh to 
eleventh dorsal vertebra. Ataxia slight. 
Has been given iodide of potassium 
freely during past year without good 
effect of any kind. For six months has 
taken morphine hypodermically and by 
mouth for the excruciating pains. 
Application of sinusoidal current 
(alternating 480 per second; voltage 55 
to from neck to painful points in 
thighs and legs for ten minutes. Relief 
of pains complete. Patient slept with- 
out morphine for the first time in 
months. The pains returned on the 
following day, same locality, in less 
severe form, and were again promptly 
relieved in the same manner. 
On the fourth day the pains did not 
return on the front of thighs, where 
their intensity had been greatest, but 
appeared on the back of thighs, lower 
third. 
Treatment continued daily for a 
week, during which time the pains 
returned twice at night, and patient 
could not resist the temptation to take 
morphine, which he had in the house. 
After ten days’ treatment (from the 
beginning) the pains ceased to return, 
patient took no more morphine, and 
expressed himself as comfortable in 
every respect, and in better health than 
for a year or more past. 
Treatment was continued every 
other day for a month, by passing 
current from nape of neck to foot-plate, 
and patient went to his home in another 
city in excellent health and spirits. This 
has continued for the past five months, 
during which I have seen him about 
once a month. Very slight pains ap- 
peared on one occasion before his visit, 
which one treatment promptly relieved. 
During his five months’ treatment he 
has taken the chloride of aluminium in 
four-grain doses, for a month at a time, 
and alternating with it phosphorus, 
strychnia and iron at intervals. His 
weight has increased eighteen pounds, 
and he appears in vigorous health. The 
knee-jerks are still absent, and the 
Argyle-Robertson pupil present. Ataxia 
not noticeable, even with eyes closed. THE “STNtJSOtDAL” CURRENT /N ELECTRO THERAPY. 
633 
No mercury or iodides have been 
administered at any time while under 
my care. I do not consider them indi- 
cated in this disease (L.). 
Case II.—Mr. B., actor, aged fifty, 
looks younger. Good physique, spare 
build, active habits. No history of or 
visible indications of syphilis. Has 
Argyle - Robertson pupils, lost knee- 
jerks, marked static and locomotor 
ataxia. Gastric crises, no lightning 
pains. Staggers noticeably even with 
eyes open; cannot stand or walk with 
eyes closed. 
Sinusoidal current passed from nape 
of neck to foot-plate. Alternations 480, 
voltage (apparent) 55, time ten minutes. 
Immediately afterwards was able to 
walk without staggering, and walked 
across room with eyes closed, which 
he could not do before treatment. Im- 
provement continued for five days under 
daily treatment. Case still in progress 
(S.). 
Case III.—Mr. C., farmer, fifty. 
Referred to me by Dr. J. B. King. 
Spare build, well developed. Father 
died of consumption. Had syphilis ten 
years ago. Has had grippe. Habits 
generally good. Has Argyle-Robert- 
son pupil, lost knee-jerks, marked static 
and locomotor ataxia with eyes open; 
cannot stand or walk with eyes closed. 
High-action gait, cannot walk without 
cane. Girdle anesthesia below nipple 
line. No lightning pains. 
Treatment: Phosphorus, gr. 1/50 t. 
d.; aluminium chloride, gr. iii, three 
times a day. 
Sinusoidal current, neck to foot 
plate. Alternations 480, voltage 25 to 
50. Improvement in ataxia so as to be 
able to walk without cane and without 
the “ high-action ” gait. Can be treated 
but once a week, owing to distance at 
which he lives. A most unpromising 
case, but showing marked improvement 
after three treatments a week apart. 
Still under treatment (L.). 
Case IV.—Poliomyelitis Anterior 
Acuta.—Referred by Dr. A. I. Carson. 
(Child) D., five and three-quarter years. 
Onset rapid six weeks ago. Helpless 
for three weeks, then some power in 
hands and arms. Can extend and flex 
thighs, but not legs and feet. Knee- 
jerks absent. Plantar reflex present. 
Tactile sensibility present. 
Electrical examination: No response 
to faradism of leg and foot muscles. 
R. D. to galvanism, which causes pain 
and complaints from child. 
Sinusoidal current applied to para- 
lyzed muscles produces contraction, and 
child does not complain of pain with 
this current. Continuous treatment 
advised, but mother would not take 
trouble to fetch child for treatment, 
though it was offered gratis. 
This case is reported in order to 
emphasize the observation that the sinu- 
soidal current acts like the galvanic in 
producing muscular contraction where 
the nerves are degenerated. It has the 
additional advantage of being well 
borne by children because of its slight 
sensory effects (L.). 
Case V.—Nuclear Palsy, with An* 
osmia and Olfactory Paresthesia, ap- 
parently due to peripheral degeneration 
of olfactory nerves. Nasal disease ex- 
cluded by a competent rhinologist.—Mr. 
E., forty-five. Specific history, for 
which course of treatment has been 
taken recently. Smell absent on right 
side entirely. On left side complains of 
a constant, very disagreeble odor of 
something burning. Has ophthalmo- 
plegia, external and internal. No ataxia. 
Knee-jerks present normal. His chief 
complaint is the disagreeable odor above 
mentioned, which is so persistent and 
annoying as to cause nausea and loss of 
appetite. 
Sinusoidal current applied daily, 
from nose to nape of neck, at first with 
partial, later with complete, relief to 
the peculiar odor; relief would last a 
day, rarely two days. Immediately after 
treatment would recognize test odors 
with both nostrils (peppermint, etc.). 
After one month’s treatment, with 
marked improvement in the chief com- 
plaint, patient ceased his visits. This 
patient thought he knew so well how 
to treat his constitutional condition that 
he looked with contempt on medical 
advice for that purpose (L.). 
Case VI. — Sciatic Peri-Neuritis 
(Syphilis or La Grippe?)—Mr. F., 
twenty-eight. Dissipated habits. Has 
secondary syphilis, and recently had an 634 
THE “SINUSOIDAL" CURRENT IN ELECTRO-THERAPY. 
attack of la grippe. Complains of 
extreme pain in loins and over course 
of sciatic nerve. Walks with great 
difficulty, and with a rolling movement 
from side to side. Prescribed K. I. Ap- 
plied sinusoidal current to painful areas. 
Effect almost magical. Pains relieved 
and gait improved at once. Returned 
in two days with similar pains less 
severe. A second application gave 
complete relief. K. I. continued (S.^). 
Case VII. — Brachial Neuritis 
(<diphtheritic?) — Referred by Dr. G. 
M. Allen. 
Mrs. G., thirty-five. Slender build. 
General health good. Complains of 
pain and inability to raise right arm, to 
put on dress, etc. Examination reveals 
marked weakness of deltoid. Pain on 
deep pressure and on slight voluntary 
movements. Cannot abduct right arm 
to a right angle, muscle somewhat atro- 
phied; also the supra-spinatus and infra- 
spinatus on same side. Partial R D. in 
right deltoid (sluggish galvanic con- 
traction, poles not reversed). No re- 
sponse to faradism. Palate reflex ab- 
sent. History of sore throat and diffi- 
culty in swallowing a few weeks ago. 
Upper arm muscles generally weak and 
flabby as compared with left arm. Sen- 
sations of numbness present. 
Treatment: Sinusoidal current, three 
times a week, to produce mild muscular 
contractions. Voltage 25 to 35; alter- 
nations 480; time five minutes. Result 
immediate relief of pains; progressive 
increase in nutrition and power of 
muscles. Duration of treatment about 
three weeks, regularly; after that occa- 
sional treatments once a week (L.). 
Case VIII.—Lead Neuritis.—Mr. 
H., thirty-five, printer. January 21, 
1896. Complains of weakness in right 
arm. Says he has had three attacks of 
paresis in that arm in three successive 
years. This one is the worst. Muscles 
of right arm, forearm and hand wasted, 
soft and flabby. Measurements: Middle 
of forearm, right 9J inches, left 10J 
inches; wrist, R. 6\ inches, L. 6f 
inches. Power much diminished as com- 
pared with left arm. Dynamometer, R. 
80, L. 200 (lower scale). 
Treatment: K. I. and sinusoidal cur- 
rent. After three treatments the dyna- 
mometer showed R. 180, L. 220. Three 
days later R. 195, L. 220. Measure- 
ments: Middle of forearm, R. 9! inches. 
Continued to improve in use of arm for 
a month, but measurements and dyna- 
mometer register unchanged. 
The gain in this case is quite satis- 
factory in every way. The failure of 
the weak arm to fully recover and 
become as strong as the left is probably 
due to two causes: (1) The previous 
attacks of paralysis; (2) the lack of 
sufficient time for complete nerve re- 
generation (S.). 
Case IX.—Left Facial Paralysis, 
complete, due to destruction of nerve by 
mastoid disease.—Miss I., domestic. In- 
ability to close left eye; mouth drawn 
to right. Left face smooth. This was 
evidently a most unpromising case for 
any treatment, but the sinusoidal cur- 
rent was applied for experimental pur- 
poses. The most annoying symptom 
to the patient was the lagophthalmus. 
After a few treatments it was observed 
that the patient could close the eye 
while the current was passing. 
Treatment for two months, rather 
irregularly on occount of the patient’s 
indifference, was attended with marked 
improvement in voluntary power over 
the paralyzed eyelid and more plump 
appearance of the paralyzed side of face. 
Patient then passed from view and re- 
turned four months later with the lag- 
ophthalmus almost as bad as ever. She 
is at present under irregular treatment, 
and improving again. 
The improved power over the orbi- 
cularis when the nerve was supposed to 
be completely severed in the Fallopian 
canal is, of course, susceptible of two 
explanations: (1) That some nerve 
fibres escaped damage and treatment 
improved their function; (2) more prob- 
ably, however, it was the “ associated” 
action of fibres reaching the muscle 
by other routes than the portio dura 
(by the third nucleus, for instance, as 
has been suggested by Mendel and 
others) (S.). 
Case X.—Left Hemiplegia from 
Cerebral Hemorrhage. — Referred by 
Dr. G. M. Allen. 
Mr. J., sixty-two, merchant, married, 
excellent habits. Patient has been hemi- 7 /1E 11S/TVUSO/DA L" CURRENT IN ELECTRO THERART. 
635 
plegic for two years, with marked con- 
tracture of flexors of left forearm and 
fingers, so that the hand is useless. Ex- 
aggerated knee-jerks, left face weak. 
Grasp, R. 120, L. 60. The long dura- 
tion of the condition, and the fact that 
he had had intelligent treatment from 
the start, with later, prolonged faradic 
treatment, rendered the case a most un- 
promising one for any treatment. Volun- 
tary power over extension of fingers of 
left hand almost nil. Cannot pick up 
pencil, button clothes, etc. Is very 
desirous of improving use of hand. 
Treatment.—Sinusoidal current from 
nape of neck to weak muscles (ex- 
tensors). Later from right parietal 
region to muscles. After a few weeks 
better control of hand movements re- 
sulted, so that he could pick up pencil, 
open and close hand fairly well. 
A feature of especial interest was 
the quickening of response and better 
control of voluntary power in the para- 
lyzed hand during the application of 
the current to the opposite parietal 
region. The long duration of the symp- 
toms would render any improvement 
remarkable in such a case, and it was 
gratifying to have the patient’s assur- 
ance that the hand was really more use- 
ful after two months’ treatment. 
The result in this case probably em- 
phasizes the fact that in every cerebral 
paralysis there exists a “functional” 
element of greater or less degree, treat- 
ment of which may be followed by im- 
provement even in apparently hopeless 
cases. This is not to be attributed, of 
course, to removal of any organic lesion, 
but simply to better functional activity 
of neighboring slightly damaged or un- 
damaged nerve elements (L.). 
FUNCTIONAL AFFECTIONS (MOTOR). 
Case XI.—Spasmodic Torticollis.— 
Referred by Dr. Wade Thrasher. 
Mr. K., twenty-four. Street-car 
conductor. Single. Onset sudden, with 
gradual increase of symptoms, viz., in- 
ability to keep head from turning 
strongly to right. The spasm yielded 
at once to the sinusoidal current, but 
returned repeatedly in even a worse 
form, the posterior rotators of the skull 
being affected. The patient’s surround- 
ings being undesirable, I thought best 
to advise him to go to the hospital, 
where he could have rest in bed and 
constant care. This was all the more 
important as I suspected an organic 
cause for the torticollis. Under the 
care of my colleague, Dr. Hoppe, how- 
ever, he has improved materially, so 
that hopes are entertained that the 
affection is functional in nature (L.). 
Case XII.—Blepharospasm [tonic). 
—Referred by Dr. R. Sattler. 
Mr. L., forty-nine. Plumber, mar- 
ried. Has had double blepharospasm 
for seven months, at times so severe as 
to disable him for work. Habits good. 
No eye cause discovered by oculist. 
Treatment by sinusoidal current 
three times a week for two weeks, with 
entire relief of symptom. During the 
first treatment patient could hold eyes 
open all the time current was passing. 
Relapse occurred, however, some hours 
later. After three or four treatments 
the spasm failed to return, and he dis- 
appeared from observation (L.). 
Case XII.—Blepharospasm [tonic 
and clonic 'with much tre?nor).—Referred 
by Dr. R. Sattler. 
Miss M., twenty-two, domestic. 
Hysterical stigmata. Has been disabled 
for her work for several months by per- 
sistent blepharospasm, varying in sever- 
ity, at times. 
Treatment by weak sinusoidal cur- 
rent, alternations 480 per second, during 
passage of which she can keep both 
eyes wide open. Treatment repeated 
twice a week, with considerable im- 
provement in two weeks. Still under 
treatment (L.). 
Case XIV.—Hysterical Aphonia 
Referred by Dr. C. R. Holmes. 
Mrs. N., forty-five, wife of a phy- 
sician. Has been in poor general health 
but is now better. Lost voice some 
weeks ago, and cannot speak above a 
whisper. No local lesion. Has had 
extra diet, hygienic exercise, rest, 
change of scene, attention to eyes, and 
“ suggestion ” treatment, all with no 
effect. 
Three applications of sinusoidal 
current to larynx and nape of neck; no 
pain; no wire brush. Complete return 
of voice (L.). 636 
THE “SINUSOIDAIT CURRENT IN ELECTRO THERAPY. 
FUNCTIONAL AFFECTIONS 
(visceral). 
Case XV.— Gastric Spasms (peri- 
odical).—Referred by Dr. G. M. Allen. 
Mrs. O., forty-five, married. Active, 
neurotic, emotional. Has had for two 
years or more spasmodic contractions, 
which she locates in the stomach. 
Usual time of onset, 5 o’clock a.m., 
waking her out of a sound sleep. These 
occur almost daily. Were cured on one 
occasion by change of climate. She has 
been given quinine in various ways and 
in full doses, with little or no effect on 
the spasms. No motor or sensory symp- 
toms elsewhere. No fever at any time. 
Treatment with sinusoidal current 
from nape of neck to epigastrium, 
repeated three times a week. Gradual 
improvement, the spasms, after six 
treatments, ceasing. Patient felt much 
encouraged, but upon ceasing treatment 
for a few weeks had a relapse, which 
also yielded readily to the same treat- 
ment (L.). 
Case XVI.—Senile Neurasthenia, 
with gastric and intestinal indigestion. 
—Relerred by Dr. G. M. Allen. 
Mr. P., sixty-five, married. Has 
had influenza recently. Much depressed 
mentally; lacks appetite and power to 
digest food. Has had tonics and digest- 
ants without benefit. Tells a charac- 
teristic “neurasthenic” story. Loss of 
weight. Pulse 80, feeble. Visual fields 
contracted. Hard arteries. Power and 
sensation fair. Knee-jerks increased. 
Urine negative. 
Treatment: Sinusoidal current three 
times weekly, from neck to epigastrium 
and abdomen. Result, in two weeks 
return of appetite, eats “ sausages and 
buckwheat cakes” with a relish. Dis- 
appearance of flatulence. Mental state 
cheerful, making plans for the future 
again. Advised to go South for the 
winter, which he finally decided to do, 
though he considered it entirely unne- 
cessary so far as his health and feelings 
were concerned. At last accounts his 
improvement continues permanent (L.). 
Case XVII. — Intestinal Atony.— 
Mrs. wife of a physician. Referred 
by Dr. E. W. Mitchell. Has complained 
of chronic constipation and flatulence 
for some years. Dietetic, medicinal and 
galvanic treatment, in skillful hands, 
have failed to give material relief. 
After a few weeks’ treatment with 
the sinusoidal current she expresses her- 
self as much improved. Bowels moving 
regularly and digestion improved. Still 
under treatment (L.). 
SENSORY AFFECTIONS. 
Case XVIII. — “Hysterical” (?) 
Neuralgia.—Referred by Dr. W. H. 
McGrew, of Pleasant Ridge, O. 
Miss R., age twenty-three, farmer’s 
daughter, a large, well-developed hand- 
some woman. No contraction of visual 
fields or other hysterical stigmata. Com- 
plains of severe pains, with “ cramps,” 
at times located chiefly in the back of 
the neck, shoulders, calves of the legs 
and tendo-achilles. Pains are constant, 
with exacerbations. Duration seven 
months. Onset sudden, following a 
severe emotional shock (death of a fa- 
vorite brother). Intelligent medicinal 
care, change of scene, etc., had failed 
to benefit the patient. 
Treatment: Sinusoidal current 55 ( ?) 
volts, alternations 960, completely re- 
lieved the pains in ten minutes. Treat- 
ment repeated every other day. Occa- 
sional return of pains for a month. 
Patient then ceased her visits for a 
month, as they were inconvenient on 
account of distance from the city. The 
pains returning, however, she resumed 
treatment, with complete relief from 
two applications. Has remained well 
for four months (L.). 
Case XIX. — Neurasthenia, with 
functional hyperesthesia and 11 shooting 
pains” in limbs.—This patient was a 
physician, age forty-seven, of good 
habits and a hard worker. The pains 
in the limbs and back were severe 
enough to make him apprehensive of a 
beginning locomotor ataxia. Examina- 
tion revealed that they were decidedly 
worse in the vicinity of an old scar of 
many years’ duration. No symptoms of 
tabes were found. 
Care in diet and the sinusoidal cur- 
rent relieved him in a few weeks, with- 
out the rest from practice which was 
advised and needed. So satisfactory was 
the relief afforded that it was difficult THE “SINUSOIDAL” CURRENT IN ELECTRO-THERAPY. 
637 
to convince him that rest and careful 
nutrition were essential to a permanent 
cure (L.). 
Case XX.—Hyperesthesia of Abdo- 
men.—Miss T., twenty-five. Complains 
of extreme sensitiveness of abdomen, so 
that the necessary manipulations of a 
dress-maker caused severe pain. 
A strong current (60 to 80 volts)( ?), 
with the highest attainable frequency 
of alternations (1,920 per second), was 
used locally. Improvement progressed 
steadily up to the eighth application, 
when the trouble was completely re- 
lieved. There has been no return to 
date (S.). 
Case XXI.—Hyperesthesia [dorsal). 
—Referred by Dr. S. C. Ayres. 
Mrs. U., thirty-five, married, three 
children. Good heredity, robust phy- 
sique. Pulse 84. Heart, lungs and urine 
normal. Nineteen years ago was in an 
out-house during a thunder storm, when 
the building was struck by lightning. 
Is positive that the boards were charred 
and burned. Her clothing and skin were 
not burned. Was found unconscious, 
and since then has had five or six “ fits ” 
at long intervals, with rigidity and un- 
consciousness. For more than two years 
past has had extreme hyperesthesia of 
right side of back (dorsal and lumbar 
regions), with weakness of left arm. 
Examination reveals a normal men- 
tal “ tone,” not emotional,” but some- 
what depressed. No speech disturb- 
ances. Right visual field much con- 
tracted. Taste absent to salt, sugar, 
and bitter on right side of tongue ante- 
riorly. No muscular rigidity, spasm or 
wasting. Grasp, right 40, left 20 (lower 
scale of dynamometer). Some weak- 
ness on flexion of left thigh. Uncer- 
tainty of heat and cold sense over left 
shoulder, arm and hand. Marked hyper- 
esthesia over an area extending six 
inches to right of spine from third dorsal 
to first sacral vertebras. Sensation nor- 
mal on opposite side corresponding. 
Touch of a wisp of cotton, without 
her knowledge, causes excessive pain 
over the hyperesthetic area noted. No 
bladder or rectal symptoms. Knee-jerks 
absent. 
The peculiar complex of symptoms 
rendered the diagnosis in this case 
somewhat uncertain for a time, but I 
was finally led to consider the hyper- 
esthesia, as well as the other symptoms, 
entirely functional, and probably of 
cortical origin, chiefly by reason of their 
peculiar distribution. This opinion was 
further strengthened by the marked re- 
lief afforded by the sinusoidal current, 
which, however, had to be applied at 
the margins of the affected area, and 
the electrodes gradually shifted as the 
sedative effect was obtained. It was 
impossible for the patient to bear for a 
moment the weight, or even the mere 
contact, of the electrode without any 
current. By means of the procedure 
adopted, however, the current was ap- 
plied to the entire hyperesthetic area. 
The patient declined to remain for 
treatment, however, and went home to 
a distant city, where she applied to a 
physician for “electrical treatment.” 
The slightest current used, which I 
suppose was an ordinary secondary 
faradic from her description, caused 
such excessive pain that she ceased 
treatment at once and returned in a few 
days to Cincinnati. 
A course of one month’s treatment, 
during which time the current was in- 
creased from to 50 or more volts 
and the alternations reduced from 960 
per second to 480, was attended with 
complete relief, which has continued 
for three months. 
Before returning home the dynamo- 
meter test registered R. 90, L. 95. The 
hyperesthesia had disappeared. The 
knee-jerks were still absent, even to re- 
inforcement. The right visual field 
remained contracted. Her general health 
was excellent in every respect (L.). 
Respecting the precise mode of action 
of the sinusoidal current, we are per- 
haps as much in the dark as we are 
with the similar problem pertaining to 
most remedies. Our limited knowledge 
of the ultimate nature of nerve-conduc- 
tion points to the probability that it is 
a “ mode of inter-molecular motion ” in 
the ultimate nerve elements. 
One explanation, therefore, of the 
mechanism of action of the sinusoidal 
current in hyperesthesias is that it 
modifies favorably and in a regular 638 
THE “SINUSOIDAL" CURRENT IN ELECTRO THERAPY. 
manner this inter-molecular motion. 
The facility with which the rate of 
alternation may be varied from 480 to 
1,920 per second, and the “ potential” 
(voltage)1 within equally wide limits, 
renders this form of current peculiarly 
adapted to the modification of neuro- 
activity. The more rapid alternations 
appear to produce a sedative effect, the 
slower alternations a stimulant action. 
The improved circulation locally and 
generally observed to follow its use in 
most cases is probably another potent 
factor in the results, by its good effect 
on tissue metabolism. 
Aside from these, the current ap- 
pears to possess in an unusually satis- 
factory degree the common action of 
all electric currents on living tissues 
—catalysis. 
For assistance and information re- 
specting the sinusoidal current and its 
relations, acknowledgements are due to 
Mr. A. L. Duwelius, of Cincinnati, 
and to Mr. J. H. Gladstone, of the Edi- 
son Manufacturing Company, of New 
York. The very satisfactory little book 
of Houston and Kennelly, before re- 
ferred to, has also been freely used in 
the preparation of this paper. 
i Where the term volts occurs in this 
paper it refers to the voltage per lamp 
volts) admitted to the primary coils. The 
voltage to the patient can only be approxi- 
mately stated on account of the impractica- 
bility of exactly measuring an alternating cur- 
rent of such high frequency. 
DISCUSSION. 
The President, Dr. Joseph Eich- 
berg: The Academy is indebted to Drs. 
Langdon and Schenck for their excel- 
lent paper, and for their kindness in 
demonstrating a new apparatus. It is 
unfortunate that the paper is of such 
character that the knowledge of the 
subject is mainly confined to the essay- 
ists, but we will be glad to hear from 
any member who may have had any 
experience in this direction. It cer- 
tainly appears to be an important con- 
tribution to our knowledge of the treat- 
ment of some organic diseases of the 
nervous system. 
Dr. A. D. Birchard: I can testify 
to the efficacy of the sinusoidal current 
as an analgesic on my own person. I 
was afflicted with a radial neuritis, 
causing severe pains at the wrist, with 
anesthesia over the dorsum of thumb, 
probably due to exposure to cold in 
driving. After the first application the 
pain was relieved, and this relief re- 
mained permanent after a few appli- 
cations. The anesthesia continued for 
some months, but it did not annoy me 
sufficiently to require continued treat- 
ment. 
Dr. M. A. Tate: I would like to 
ask the essayist if he considers the sinu- 
soidal current a substitute or equivalent 
for all other electric currents for medi- 
cal purposes? 
Dr. S. P. Kramer: The especially 
valuable feature of the sinusoidal current 
appears to me to be its power ot pro- 
ducing muscular contractions of a 
tetanic character where faradism fails, 
and this without the cutaneous pain of 
the faradic current. It is superior to 
the galvanic current as a nutritional 
agent if, in nerve degenerations, we 
can produce a more continuous contrac- 
tion of the muscles. The sensory effects 
are of less importance, since we may 
obtain them in some degree from other 
forms of current. 
Dr. Joseph E. Brown: I under- 
stand from the remarks of the essayist 
that this is an induced current, the 
poles of which change rapidly. Why 
would we not have the same effect with 
a rapidly interrupted galvanic current? 
With the ordinary rheotome we do not 
have interruptions of sufficient rapidity. 
Dr. Kennon Dunham: I desire to 
ask the essayist what the value of the 
sinusoidal current is as a diagnostic 
agent? 
Dr. Langdon: With reference to 
Dr. Birchard’s experience, his case is THE “SINUSOIDAL” CURRENT IN ELECTRO TILER APT. 
639 
not amongst those reported. I regarded 
the lesion as a radial peri-neuritis, prob- 
ably due to exposure to cold in driving. 
The analgesic effects of the current 
were all that could be desired. 
In reply to Dr. Tate’s query, I would 
state that the sinusoidal current cannot, 
in my opinion, be looked upon as a 
substitute or equivalent for any other 
current. Its wave form, as shown in 
the diagrams, indicates that it is a dis- 
tinct thing in itself, not a modification 
of any other current. Its therapeutic 
effects also point to this conclusion. 
I entirely concur in Dr. Kramer’s 
remarks as to the value of this current 
in nerve degenerations, and the case of 
polio-myelitis recorded shows its desir- 
ability in these forms of paralysis. 
Dr. Dunham’s question respecting 
the diagnostic value of the sinusoidal 
current cannot be properly answered at 
present, for the reason that all recorded 
observations bearing on diagnosis have 
been made with the galvanic and faradic 
currents. 
To Dr. Brown’s question I would 
reply that any rapidly interrupted gal- 
vanic (direct) current has nothing in 
common with the sinusoidal wave. 
Such a current as the doctor refers to 
would be a pulsating (De Watteville) 
current, not an alternating current of 
any kind.