THE NATURAL POSITION OF THE UTERUS AND HOW IT IS SUPPORTED.
THE uterus is not a stationary fixture in the female pelvis, but enjoys
a mobility within physiological bounds, which in itself explains the
great diversity of opinions which may and do arise respecting the
normal or abnormal position of the womb in any given case.
When the surrounding organs and tissues of the womb are in a healthy
condition, and the abdominal walls are not compressed by the weight
and pressure of skirts, nor the liver or diaphragm forced down towards
the pelvis by a tight-fitting corset, the organ is movable in every
direction, without the slightest pain or suffering.
The uterus is not tied down by any ligaments, as one might imagine from
a description of the several ligaments that constitute only in a small
degree its support, for it changes its position in retching, coughing,
breathing, singing, walking and all other violent movements.
The question now naturally arises: What is the normal position of the
uterus, and what constitutes its natural supports? To answer this
interrogation is to controvert one of the most baneful fallacies
in gynecological practice, for the amount of torturing and useless
doctoring to which women are constantly subjected, owing to some
fancied displacement of the womb, illustrates the force of precedent
or of accepted opinions, that were fortified by years of erroneous
teaching.
It was supposed until quite recently that when the body of the womb
was inclined horizontally forwards, this was unnatural or a sign of
disease, until Prof. B. S. Schultze, director of the gynecological
clinic of Jana, successfully controverted this doctrine. In his work
“_Die Pathologie und Therapie der Lageverænderungen der Gebærmutter_,”
which is the most classical work extant on displacements of the
uterus, says: “From the _post-mortem_ findings it was inferred that
the uterus occupied in the _living_ woman the same position as in the
cadaver; such an assumption did not take into account the actions of
the muscles on the position of the uterus in the living subject nor
the intra-abdominal pressure which is entirely absent after death, so
that the dead organ naturally gravitated backward after the remains had
lain for several days on the back.” Another observer, Dr. Hach, found
in a number of cases that he had examined during life, the uteri bent
forward or antiflexed; twenty-four hours after death he discovered the
same uteri in an opposite direction or retroflexed.
This and similar subsequent researches have demonstrated the fact that
when the body of the womb rests on the bladder it is not in an abnormal
position as formerly supposed and called _anteversion_ or anteflexion,
but that it is natural for it to be so, and when the body is elevated
and its axis forms an obtuse angle with the horizon, the inclination is
a _post-mortem_ condition.
With these precursory remarks I am now able to answer the first clause
of our query, and would say that the uterus is in its normal position
when its long axis is nearly parallel to the horizon or at right angles
with the perpendicular or long axis of the body. The normal position of
the uterus is modified when the bladder is full or distended, for this
lifts the body of the uterus upwards, thus temporarily making an acute
angle with the vertical axis of the body, which was formerly considered
to be the permanent and natural pose of the organ.
In referring to the bony pelvis, Plate I, it will be observed that the
same is in the nature of a canal, for the passage of the child into
the world. At other times than during the child-bearing process, this
canal must be effectually closed to perfectly retain its contents. To
accomplish this purpose it is provided with a bottom or floor, which is
to give this necessary support, not only to the organs that the pelvic
cavity contains but also to the abdominal viscera that are superimposed
upon them. In order to accomplish this, its outlet must be as
effectually closed as the bottom of a box or barrel in which material
things are stored for the purpose of carrying them from place to place.
In the human subject this bottom is called the pelvic floor, because it
serves the purpose of a bottom or floor to the pelvic canal.
The _pelvic floor_ is not a simple structure but a complicated
arrangement of organs and tissues. If we begin to examine it from
below upwards, we first have its outer covering in the skin; then, the
superficial and deep fascias, the triangular ligament of the bladder
and a group of interlacing muscles. The organs that enter into the
composition of the pelvic floor and interwoven with the preceding
structures, are the bladder, the vaginal walls, the rectum and
connective tissue. Examine Plate II.
Through this floor there are several openings, which are guarded by a
special set of constrictor muscles that are termed _sphincters_. These
are sufficiently strong in the bladder and rectum but in the vagina
they would be entirely insufficient to close this canal effectually.
The vagina, or, for our purpose, it will be clearer if we say “_vaginal
canal_,” divides the pelvic floor into an anterior and posterior
segment, and it is by means of this division that the whole structure
of the pelvic floor is weakened; this will be perceived at a moment’s
reflection, when we compare it with the pelvic floor of the _male_,
who has no vagina; and for this reason men are never troubled with the
_prolapses_ to which women are liable. Nature, however, has made an
attempt to compensate this physical defect in a manner that reduces
the weakness occasioned by the vaginal canal to its minimum. The
vaginal canal does not enter the pelvic cavity in a directly upward or
perpendicular course, but obliquely upwards and backwards, as may be
seen by referring to Plate II. The result is that the intra-abdominal
pressure falls on the vaginal walls from above, and thus compresses
and approximates the anterior and posterior walls of the vagina
to each other, so that it constitutes a self-closing valve, but,
notwithstanding all these provisions, this slit or opening through the
pelvic floor still remains the weakest point of the inclosure for the
pelvic and abdominal viscera. When the causes are sought that underlie
the various displacements of the uterus, they are generally to be found
in an impairment of the pelvic floor, through some changes or accidents
that are peculiar to pregnancy and delivery.
As we are also to inquire in the succeeding chapter into the
displacements to which the womb is liable, it would greatly assist our
understanding if we first got an idea of what constitutes the natural
supports of the uterus? The word ligament is defined as anything that
ties or unites one thing or part to another; a bandage; a bond. This
is the _idea_ in the popular mind, so that when the terms broad and
round ligaments of the womb are employed it is supposed that they are
for the same purpose for which ligaments are usually intended. This
is, unfortunately for a clear understanding of the subject, a great
mistake, because these ligaments are an exception to the generally
accepted meaning of the term, for they neither tie nor support the
uterus in its natural position. One may readily imagine that this
erroneous conception would lead to a mistaken course in the treatment
of most cases of displacements, because too much importance is bestowed
upon structures that have no physiological bearing on the disease.
Drs. Hart and Barbour, of Edinburgh, in their “Manual of Gynecology,”
which is the most scientific and practical work that has lately
appeared in the English language, have this to say in speaking of the
support of the uterus: “The question of the support of the uterus
is still disputed. The broad and round ligaments have nothing to do
with its support, they are only useful as giving fixed points for the
contracting uterine muscles during parturition. The chief support is
the compact unbroken pelvic floor, on which the uterus rests just
as one sits on a chair. It is the whole pelvic floor that supports
the uterus and viscera, not the perineum alone.” The perineum (see
anatomical Plate II) is only a small though strong part of the pelvic
floor. If the reader will now patiently review the organs that,
together with the other tissues, constitute this floor, and this can be
most profitably done by studying Plate II, there can be no confusion of
ideas whatever. In the following pages I have occasion to refer to what
is understood by the term pelvic floor.