AXIS-TRACTION FORCEPS THE 
PRINCIPLES AND APPLICATION 
OF 
AXIS-TRACTION FORCEPS 
WITH SPECIAL REFERENCE TO THE INSTRUMENT 
DEVISED BY TARNIER 
By Stanley P. Warren, m. D., 
Portland, 
Reprinted From Transactions of the Maine Medical 
Association 
Portland, Me. 
BROWN THURSTON COMPANY 
PRINTERS THE PRINCIPLES AND APPLICATION 
OF 
A XIS-TR ACTION FORCEPS, 
WITH SPECIAL REFERENCE TO THE INSTRUMENT 
INVENTED BY TARNIER. 
STANLEY P. WARREN, M.D., OE PORTLAND. 
The argument attempted in this paper is to show, not which 
is the best of two operations, forceps or version, in delivering 
from the brim, but, when forceps are decided upon, what is 
the best forceps to be used. Your discussion, then, will nat- 
urally be restricted to the merits or demerits of the particular 
forceps in question. 
The extraction of a child from the pelvis at the brim does 
not depend simply upon the brute strength of the operator. 
If the decision has been made that forceps are to be used, the 
intelligent operator will ask himself: First, “ Does one kind 
of instrument have any special advantage over some other for 
the purpose in view?” Experience and common sense both 
tell him “yes.” Second, “ In which direction shall I pull?” 
There is a choice here, too. Third, “Is time an important 
element in success?” Deferring for further consideration the 
answering of the first two of these questions, in regard to the 
last it may be said here, that though either extremes of time 
are to be rejected, it appears to be established that it is the 
operation, as a whole, that is dangerous, rather than the mere 
pressure of the instrument. Statistics show that it is not the 
forceps alone, but the prolonged and difficult labor, which is 
the chief cause of idiocy in such cases as are attributed to the 4 
forceps by Winckler and Bollaan. In 810 cases of idiocy, 
35 (4.3 per cent) were placed to the forceps, while 316 (26.6 
per cent) were charged to the prolonged or difficult labor. 
Annual of the Universal Med. Sciences, 1890, Vol. 2, loc. sic 
For instance, the head is found engaged at the brim and 
fixed there by some one of the many causes which check de- 
scent. The accoucheur decides to apply the forceps, using his 
well-tried and trusty pair which have delivered hundreds of 
» women and have never failed him. He pulls and sweats, for 
hours perhaps; something must come, and something will, if 
he sticks to it long enough. Finally the child is dragged out 
decidedly the worse for wear, and the woman has present or 
future mutilations, from which date a life of pain or invalidism. 
Such cases are common our broad land over. Now, in the 
light of all the advances in medicine which the close of this 
century claims with pride and honor, has he done the best for 
his patient he could ? While other specialists have profited by 
the progress in anatomy, diagnosis, instruments, in the tactile 
sense, in the dynamics of the special organ, can the obstetri- 
cian, in conscience, be content to stand where Ramsbotiiam 
and Denman left him? The highest skill, acquired from spe- 
cial study, from the mechanical instinct, from that inexplainable 
natural fitness, and from constant practice, that skill alone 
should attempt these desperate cases. Why should one be so 
quick to appreciate his deficiences, when the eye or the ear is 
involved, and yet think himself fit for the emergencies of the 
most important of all specialities, obstetrics, when his stock in 
trade is a bichloride tablet and a Simpson’s forceps? One of 
the brightest teachers and operators of New York City said, 
in the Obstetrical Journal for May 1892, ‘‘the teaching is be- 
ginning to prevail that obstetrics, as a science, carries with it 
something more, than the ultimate e xpulsion of the foetus by 
nature, or its extraction by art. The thoroughly trained ob- 
stetrician of to-day trealizes that his chief responsibility lies in 5 
so conducting labor, in so watching its progress, that interfer- 
ence be not forced upon him, but deliberately elected.” 
In using forceps at the brim, there appears to be a general 
misconception of the true mechanical principle involved. The 
instrument selected by a large majority of operators is the 
common long forceps. All varieties of this, Hodge, Simpson, 
Elliot, or the Portland (which are the varieties most used 
in this vicinity) are based upon the Smellie forceps. 
Slide No. 1,* Smellie’s forceps, from Lusk’s obstetrics. For 
a hundred and fifty years the English-speaking world has 
fixed upon this as the best form for in the excavation. It 
was never intended by Smellie himself for the brim, but only 
when the head was well in the cavity. Its general shape is a 
curve, wdiose cord is from the tip of the blade to the end of 
the handle. 
Slide No. 2, Simpson’s forceps, with a line drawn from tip 
to tip, representing the cord described. 
Power is exerted with it in the line of the cord, viz.: it draws 
mainly upon a line in front of the instrument. Now suppose 
that the bony rim of the pelvis was incomplete at its anterior 
third, and that here the gap was filled in with elastic tissue. 
In such a condition the Simpson forceps would do well enough 
when used at the brim. For since, with all modifications of it, 
power is expended in a line of draught anterior to the blades, 
the head must be pulled out of the pelvic rim, and directly 
forward of the normal line of descent through the supposed 
gap. But with the natural pelvis, any form of Simpson’s for- 
ceps draws the part grasped forward against the firm symphy- 
sis and pubic rami, which stand directly in the way of such 
exit. And here is just the difficulty with the common long 
forceps: it draws the head out of its natural path of descent, 
the axis of the pelvic basin, and into an unnatural one, against 
which the pubic arch is an impassible barrier. 
* The paper was illustrated by the sterioptican, and the slides were shown, 
as numbered. 6 
Two things have delayed the answering of this problem — 
how to draw the head through the birth-canal in the line of 
its least resistance. First, the limited knowledge of the female 
pelvis; and second, the conservatism of the general practi- 
tioner. While it is not necessary to more than allude to the 
latter, of the former this may be said : The anatomy of the 
student and of the practitioner are two altogether different 
things. The student learns in the dissecting-room the major 
details of the female £>elvis, and retains them to about the 
same degree which he does that of the other parts of the body. 
The obstetrician finds that his memory must be of parts as 
related to the whole rather than of the details of independent 
tissues. And it is specially to be remembered that very re- 
cently our knowledge of the obstetrical pelvis has been mate- 
rially changed, by the facts that are established from frozen 
sections of the pelves of women dying in actual labor. The 
writings of Hart and Barbour and Braun iell us that much 
was left untaught, or taught wrong, in the older text-books. 
One point — a very important item in the obstetrical pelvis — 
these frozen sections correctly settle, the true place of the 
sacro-vertebral angle. The promontory of the sacrum is upon 
one side of the birth-canal, like a jetty upon the bank of a 
stream. It diverts the head out of a direct downward course, 
to drive it forward upon the opposite wall, the pubes. The 
planes of the pubes cause a refluent current, and the moving 
body is driven at a second angle, over again to the sacral side. 
The sacrum and coccyx continue in turn the descent, at still a 
third angle, and the child glides down, and now forwards, 
along their curves, to finally go through the outlet at a last 
and fourth angle. Thus the promontory is the initiatory ob- 
stacle to delivery, and is a most important factor in fixing the 
route, which ends in birth. When a woman is lying on the 
back, we are apt to think of the promontory as situated too 7 
low down for its proper position in the pelvis, and do not tilt 
the pelvis forward enough. 
Slide No. 3 shows a tracing from a plate by Barbour of a 
frozen section of a pelvis taken from a woman dying in labor, 
giving the normal position of the promontory, in its relation 
to the pelvis as a whole. The slide also illustrates the state- 
ment of Parvin, “ the angle made by the antero-posterior 
diameter of the inlet, and a line representing the axis of the 
body, is from 130 to 140 degrees. The sacro-vertebral angle 
is nearly four inches higher than the superior angle of the 
pelvic joint.” — Pawin's Obstetrics, loc. cit. The axis of the 
inlet, then, is not, as cbmmonly thought, vertical, or from 
behind forwards, but at right angles with the plane of the 
inlet, and therefore the first part of the descent of the head is 
downwards and backwards. Hence it follows that traction, 
with forceps at the brim, must— at first — be downwards and 
backwards, if the child is to follow the true path of descent. 
The slides now shown illustrate both the true and falsely rep- 
resented positions of the promontory, and indicate certain 
other parts of the pelvis relative to this paper. 
Slide No. 4. From Lusk’s Obstetrics, 1884, edition, page 
349. The picture from which this slide is made is incorrect in 
several particulars; the promontory is too low as regards the 
symphj’sis. The uterus at its junction with the vagina, and 
the vagina itself, is not normal, nor the rectum. Probably the 
picture was intended to be schematic rather than anatomically 
exact, but as it is it is misleading. 
Slide No. 5. From an Atlas of Gynecology and Obstetrics, 
published by Wilde & Co., in 1884. The child is represented 
at term, with the uterus, the pelvis, and its contents in antero- 
posterior section. The vagina and rectum are drawn widely 
dilated, though labor has not begun, and the cervix is grossly 
inaccurate. 8 
Slides Nos. 6, 7, 8, I am able to show through the kindness 
of Dr. Gordon. 
They are photographs of plates illustrating an article read 
by Dr. Barbour of Edinburgh, before the British Obstetrical 
Society, and are the property of Dr. Gordon, who kindly 
loaned them to me for this paper. They are line drawings of 
frozen sections of the pelves of women dying in actual labor, 
and are therefore anatomically correct. Points to be specially 
noted are the following : 
Slide No. 6. First stage. The promontory, center of the 
inner face of the symphysis, and the end of the coccyx, are 
nearly at the angles of an equilateral triangle. The axis of 
the plane of the inlet is from before backwards. The cervix 
is still closed. The vagina and rectum are also closed, the 
bladder is contracted, and the perineal body is rectangular 
rather than pyramidal, as commonly drawn. Notice particu- 
larly that the head at the inlet points backwards rather than 
forward. 
Slide No. 7. Second stage. The head points directly down- 
wards, and now rests upon the floor of the pelvis, the bag of 
waters is well formed, the uterus and vagina are now one canal, 
the rectum is slightly compressed against the sacrum and 
coccyx, while the anus is widely dilated, the perineum is thinned 
and stretched forwards, and the bladder is pushed above the 
symphysis and contracted. The slide shows beautifully the 
molding of the head to conform to the curve of the cavity. 
Slide No. 8. Third stage. The uterus is empty, its cavity 
closed except for a small space near the fundus, the uterus as a 
whole has settled down in the cavity, and in so doing has 
closed the upper part of the vagina and rectum, while then- 
lower portions are more or less open. The open space in the 
upper zone of the uterus will explain how hemorrhage after 
delivery will sometimes persist, though the uterus is apparent- 
ly firmly contracted. 9 
Slide No. 9. Showing the position of the child in the uterus, 
from a frozen section after labor has begun ; from Braun. 
American System of Obstetrics, Vol. 1, page 559. The child 
presents in the first cephalic position, the head points back- 
waids and downward and has descended nearly to the floor of 
the pelvis, the amnionic sac reaches to the vulva and is just 
ready to rupture, and the perineum is rectangular. The pelvis 
is tilted forwards so much that the promontory is nearly ver- 
tically above the symphsis. 
Slide No. 10. The uterus and the parturient canal, the 
child removed. From Braun. Lusk's Obstetrics, 1884- edi- 
tion, page 182. It is intended to show by this plate that the 
axis of the plane of the inlet is downwards and backwards, and 
that therefore the draught of the forceps must be downwards 
and backwards, when extraction is to begin at the inlet. 
From what has thus far been said, and shown, of the topog- 
graphy of the obstetrical pelvis, it would seem evident that 
there is no such thing as a universal forceps, equally good for 
all stages of delivery. A carpenter does not try to do all kinds 
of planing with only one kind of plane, but jirovides himself 
with various ones, each for a special purpose. Just so the 
obstetrician should have different tools for different emergen- 
cies, for there is no greater mistake than the old maxim, that 
a good workman can do good work with poor tools. 
One of the pressing needs of the accoucheur has been a 
tractor which would pull in the true obstetrical axis. It should 
be remembered that the axis of the bony pelvis is somewhat 
different from the axis of the dynamic pelvis or the birth- 
canal. 
Slide No. 11. The dynamic pelvis. “If the presenting pole 
of the frntus enters the inlet in aline perpendicular to its plane, 
the emergence of that pole from the vagina will be in a line 
perpendicular to the prolonged previous line. Hence, accord- 
ing to later writers, a curved line does not represent the line 10 
of the direction taken by the presenting part in passing through 
the birth-canal. A cast < >f the bony pelvis, and the canal formed 
at the expense of the soft parts, shows that the completed cav- 
ity is not a curved, but chiefly a cylindrical canal. This cavity 
has its fundus at the coccyx, and the presenting part of the 
foetus descends in a straight line to the fundus. The cavity is 
there closed, but an opening upon its anterior wall, 
and the line of direction now becomes one nearly perpendicu- 
lar to that of descent.” Pawin's Obstetrics, page Jf[. In 
the American System of Obstetrics, Vol. 1, page 449, the term 
is thus defined: “The axis of the cavity of the pelvis is a 
curved line passing through the center of the pelvic canal, and 
parallel to the face of the sacrum and coccyx. In other words, 
the axis of the pelvic canal is a curved line, identical in its 
curvature with the curve of the hollow of the sacrum and coccyx. 
When we examine a number of sacral bones, we shall find that 
no two are alike in their curvatures ; some are nearly straight, 
some curved almost to deformity ; between these two extremes 
there will be found every shade of different curve. Hence it 
follows, that the axis of the pelvic canal is not a fixed mathe- 
matical curve, but is really a line differing in each female, and 
depending absolutely on the curvature of each individual’s 
sacrum and coccyx.” 
Slide No. 12. Impressions of pelves, from specimens in the 
Medical Museum of the University of Pennsylvania, showing 
the difference in the sacral curves.—American System of Ob- 
stetrics, page 550, Vol. I. 
It seems, therefore, to be accepted by authorities, that the 
natural path of the child through the pelvis is not a fixed 
curve, whose radii are of equal length from a given center, 
but that it has every grade of angle, as varied as each pelvis 
differs from every other. For the present purpose, the pas- 
sage outward of the child, beginning with its start from the 
inlet and ending with its birth at the outlet, may be divided 11 
into three stages. In the first third the direction is backward 
and downward, or even perpendicular to the plane of the in- 
let, and ends when the head rests upon the pelvic floor. In 
the second third the direction changes, by a relatively acute 
angle, to a more forward movement, and in the third and final 
stage ends with the head directed upward. With this state- 
ment of the path of the child understood, it will be clear, per- 
haps, why the common long forceps is not the instrument to 
be chosen for delivery at the brim. It is impossible, and I am 
speaking, of course, only generally, to depress its handles 
enough to pull in the axis of the superior straight. I am 
aware that Albert Smith advocated the plan of the opera- 
tor’s grasping the handles at the lock as the fulcrum, while 
using the other hand at the extremity of the handles as a lever. 
“ Though force is wasted by pressure upon the symphysis, 
still children are not unfrequently so delivered without great 
damage to the mother.”—American System of Obstetrics, Vol. 
11, page 1J/.8. But in a long delivery few have the necessary 
endurance for this double action, a pulling and pushing, and 
I think that there have been devised better methods of gain- 
ing the desired result. 
An instrument capable of working in the natural canal, then, 
is theoretically required, and such a want has been practically 
met. Traction in the axis of the pelvis has been proposed a 
number of times since Chamberlain’s day. Herman, in 1840, 
applied traction rods to the common forceps arms, but the idea 
seemed to have attracted little or no attention, and various 
other makeshifts, with cords and metal rods, have been tried. 
In 1877 Tarnier introduced his instrument, and while there 
are other ways of attaching the traction arms to the blades, 
his forceps, as a whole, has received the most favor. “ The 
instrument has been considered as marking a new era in ob- 
stetrics, and as being the only important change since Levret 12 
gave the forceps the pelvic curve.”—Pamiris Obstetrics, page 
651. 
Slide No. 13, Tarnier’s forceps, from Cazeaux’s Obstet- 
rics, 1889 edition, page 963. 
Slide No. 14. Wells’ axis-traction attachment, applied to 
Elliot’s Forceps, from Cazeaux’s Obstetrics, page 963. 
Slide No. 15. Brues’ axis-traction forceps, from Parvin’s 
Obstetrics, page 652. The particular thing to be noticed, in 
all these varieties of axis-traction forceps, is the ingenious way 
in which has been carried out the main design, which is, to be 
able to draw not only downwards but backwards at the same 
time. 
Slide No. 16. Drawing showing Simpson’s and Tarnier’s 
forceps, with their principle of working contrasted. In the 
former the “ line of draught ” is shown to be a line drawn 
from the tip of the spoon to the tip of the handle. In the 
latter the “ line of draught ” is shown to be a line drawn 
through the spoon, and continued along the secondary handle. 
This change in the direction of the traction is obtained by 
attaching a second pair of handles to the heel of the blades. 
By using these the line of draught is, as VVinckel says, “in 
the prolongation of the blades,” straight down the birth-canal, 
rather than toward one side of it, as it is when the common 
long forceps are acting. 
Slide No. 17. Drawing of section of frozen pelvis, from 
Barbour, showing head at the brim, with Tarnier’s forceps 
applied, to demonstrate that these instruments act in the center 
of the canal, when the secondary handles are used. The great 
advantage offered in this plan of forceps, is that with it the 
operator supplies an effective power in a natural and desired 
direction. With all respect to the opinions of those present, 
it seems to me to be an error of judgement to attempt to ex- 
tract from the brim with the ordinary long forceps, reasoning 
from the arguments already advanced and from personal ex- 13 
perience. It inevitably draws the head too far forward 
against the anterior rim of the pelvis, which can be passed 
only at the expense of what, I claim, is needless time and 
strength. The German, Wintckel, one of the accoucheurs of 
the world, though not recommending the Frenchman, Tar- 
nier’s, particular form of instrument, does accept the general 
idea, and gives it his earnest approval in these words. “Ex- 
tensive experience, among these nations who employ forceps 
in cases where the head is still very high and freely movable, 
or where only a small segment of.it has entered the pelvis, and 
in contracted pelves with the head high up in the transverse 
diameter, has shown that the ordinary forceps are not suitable, 
because with them traction in the direction of the axis of the 
pelvic inlet is very difficult, and the head has not sufficient 
freedom of movement.” WinckeVs “ Text-Book of Midwifery,” 
page 703. 
The indications for axis-traction forceps are briefly as fol- 
lows. It is hardly necessary to say that it is an instrument for 
special needs, and that it can do immense damage as well as 
good, so that special care should be taken in using Tarxier’s 
or any other variety of this form of forceps. It is intended 
when the head is arrested at the inlet and forceps are requisite. 
Occiput-posterior positions are particularly suitable for it, 
since the head is more readily drawn dovn to the floor of the 
canal by the traction bars, when the usual forceps will com- 
plete the delivery. As might be expected, in cases of pendu- 
lous abdomen the axis-traction instrument is specially useful. 
When forceps are needed for the after-coming head it will be 
a valuable assistant. Other cases, which will occur to you, I 
will not take time to specify. 
The mere application of the blades offers no special difficul- 
ty. To obtain the full benefit of the principle, it is important 
that the woman should be placed upon the bed with her hips 
well forward, so that the operator can pull sufficiently far 14 
back enough. The blades are applied with reference to the 
pelvis, rather than to their position on the child’s head. Care 
should be taken, also, that the blades are inserted high enough 
to firmly grasp the head, and when fitted, the binding screw 
is tightened until the head will not slip out when a hard pull 
is made. Traction is made by the cross-bar handle alone, and 
with the rods lying on the perineum. 
Slide No. 18. Showing traction with Tarnier’s forceps, 
from Parvin’s Obstetrics, page 648. 
I have noticed that at first the pull is rather a push than a 
pull, for the reason that to draw backward, as related to the 
woman, is to push awav from the operator. The binding screw 
ought to be frequently loosened, so that the child’s brain shall 
not have its circulation too much interfered with. When the 
head is visible between the blades, the handles should be 
brought to a horizontal position. As soon as the perineum 
begins to stretch and the anus opens, then carry the handles 
upward. 
Slide No. 19. Protecting the perineum and illustrating the 
position of the handles at the outlet when delivering with Far- 
nier’s forceps, from Parvin’s Obstetrics page 662. 
“ The extraction of the head, according to its position in the 
pelvic inlet, is begun in the first position of the forceps with 
the handles directed downward. As soon as the head is visi- 
ble between the blades, we bring the handles to a horizontal 
second position—and, when the perineum begins to stretch 
and the anus opens, we carry them upward in the third position, 
in order that we may roll the head out under the symphysis 
about its transverse diameter.”— Winckel's Obstetrics, page 702. 
Though the Tarnier instrument looks somewhat formida- 
ble and complicated, yet a little experience with it shows that 
its real advantages far outweigh these apparent evils. Lusk 
puts it very happily when he says, “to one accustomed only 
to the familiar forceps, the facility with which delivery can 15 
be accomplished with Tarnier’s forceps would seem hardly 
credible.” It has been my usual custom to remove the Tar- 
dier instrument (the special variety of axis-traction forceps 
with which I am practically familiar), when the perineum is 
reached, and to substitute a lighter pair, thereby incurring less 
risk of doing damage to the parts about the outlet. 
Every general practitioner has to see something of that old- 
est branch of medicine, obstetrics. Most respond to its calls 
because they have to, rather than because they want to. A 
few find it a most fascinating study, despite its toils and dan- 
gers. When the public’s eyes and noses are out of order, it 
insists upon the services of the specialist, one who has demon- 
strated his ability to treat such delicate organs by testimonials 
of soecial training. But it allows any one, man or woman, 
learned doctor or ignorant peasant, to assume the responsibil- 
ity, of conducting delivery without let or hindrance. 
The time is ripe for the recognition by the profession of the 
speciality of operative midwifery, for which there is as much 
need as there is for that of the oculist or the gynecologist. 
Not every one can be a successful obstetrician. There is no 
organ in the body that will make such tremendous demands 
upon one’s skill, coolness, and ready invention, as a pregnant 
uterus. And the same dear public is slowly coming to the 
opinion that the skilled workman is as necessary to its preg- 
nant woman as it is for its other diseases. In fact, this paper 
is a plea for the skilled workman with skilled tools. 
The following analysis of 19 cases is given, all in private 
practice. It includes first trials, and also those when more 
accustomed to the instrument: 
In counsel, 8 cases; personal cases, 11. Primiparae, 10; 
multiparae, 9. 
Positions — head, first, 10 ; second, 2 ; third, 5; shoulder, 1; 
neck, 1; both these last two were changed by external version 
to cephalic presentations and delivered by the Tarnier. 16 
Reasons for use — disproportion, 9; fibroid in cervix, !; 
straight pelvis, 4 ; pendulous abdomen, 3 ; hydrocephalic head,l. 
Average weight of children — 8.75 pounds ; living, 12 ; still- 
born, 6; unrecorded, 1. 
Causes of death, excluding the forceps — tight cord, 3; de- 
formed pelvis, 1; long attempts at extraction previously ex- 
erted, 2; hydrocephalic head, with contracted pelvis, 1. 
This summary of the paper is offered that the special points 
may be grouped together for particular attention. 
1st. Obstetrical emergencies need not only special skill, but 
also special instruments. 
2d. The axis of the brim being from before backward, the 
line of draught of the obstetrical forceps applied at the brim 
should be from before backward. 
3d. Since the line of draught of the common long forceps 
is forward of the center of the birth-canal, therefore this for- 
ceps is not suitable for delivery at the brim. 
4th. The symphysis-pubis is the chief obstacle which weak- 
ens the full working power of the Smellie type of forceps at 
the inlet. 
5th. The axis-traction principle of delivery is the only one 
thus far published, which acts in natural directions at the brim. 
6th. Therefore this is the correct forceps to be applied at 
the brim.