A posterior repair is generally performed in conjunction with
a perineorrhaphy to correct a rectocele and to reconstruct the perineal
body. A rectocele is a hernia which develops when the rectovaginal
fascia is insufficient to support the anterior rectal wall and the
rectum prolapses through the levator sling. The strength of the
posterior vaginal mucosa is insufficient to prevent prolapse of the
anterior rectal wall.
The purpose of the site specific posterior repair is to reattach the
torn rectovaginal fascia to its orginial position.
Physiological Changes: The anterior rectal wall is reduced to
its normal anatomic position and is prevented from prolapsing into
the vagina. In severe cases, this prolapse can be of such magnitude
that defecation becomes incomplete and difficult.
Figure 1 shows a cross section of the pelvis
with the patient in a dorsal lithotomy position. The
rectocele is demonstrated.
A bimanual examination under anesthesia is
performed to differentiate between an enterocele and a rectocele.
Observation of the perineal body is made to determine the extent
of reconstruction needed. |
Figure 2 shows a vaginal view of
the rectocele protruding out of the vagina. The labia are
retracted with interrupted sutures if needed. Allis clamps are
applied to the posterior vaginal mucosa at the upper extent of
the rectocele. |
The operation is begun by making
a transverse incision at the hymenal ring. The length of
this incision is determined by the degree of tightening required
at the forchette. It is sometimes helpful to grasp the apices
of this incision with Allis clamps and pull them together to
be able to judge the ultimate caliber of the introitus at the
end of the repair and adjust accordingly. An additional Allis
clamp is placed in the midline at the top of the rectocele. In
large rectoceles, a series of midline clamps may be necessary
to provide traction for dissection and to keep the operator's
incision in the midline.
A Kelly clamp or Metzenbaum scissors is inserted
under the posterior vaginal mucosa, dissecting the posterior
mucosa off the rectovaginal fascia. By
opening the jaws of the instrument, dissection occurs and blood
vessels are pushed aside. A midline incision is then made in
the mucosa. This process is repeated until the superior apex
of the rectocele is reached.
An additional incision is made in
the perineal body, removing a triangular section of perineal
skin which is outlined by the dotted line. This will
expose the aponeurosis of the bulbocavernosus muscle. Care
should be taken to only remove the skin. |
The insert shows the obstetrical
etiology of the rectocele as the fetal head is coming through
the pelvis, the rectovaginal fascia can be torn in several places.
One can see the rectovaginal fascia torn and the rectum compressed
against the sacrum. |
The vertical incision in the posterior
vaginal mucosa has been made, and the edges are held with Allis
clamps. The rectovaginal fascia is dissected off the posterior
vaginal mucosa. The apex of the rectocele is held in an
Allis clamp. The dissection of the rectovaginal fascia
off the vaginal mucosa is started with a scalpel but completed
with a Metzenbaum scissors or open sponge. It is helpful
to place your index finger behind the vaginal mucosa as you dissect
to prevent "button-holing" of the vaginal mucosa. |
With exposure one can find the torn
edges of the rectovaginal fascia. The most common cause of a rectocele
is the transverse tear of the rectovaginal fascia off the superficial
transverse perinei muscle. Tears off the uterosacral ligaments
and peri-cervical ring are seen with enteroceles. The edges of
the fascia can be grasped with Allis clamps and brought down into
position. One should notice that the superficial transverse
perinei muscle is shown intact. It must be reapproximated if it
is also torn. One can visualize the rectum through one of the tears
in the rectovaginal fascia inferiorly. |
Figure 7 demonstrates an extreme tearing
of the rectovaginal fascia. A simple suture repair is not adequate
for this severe degree of tearing, and this patient is a good candidate
for a graft. |
Plicating the levator ani in the midline
over the rectum as was previously described in traditional descriptions
is an example of what not to do during a posterior repair procedure.
Plication of the levator ani muscles increases postoperative pain
and risk for de novo dyspareunia. |
What NOT
to do!
The rectovaginal fascia is identified
and reapproximated to the uterosacral ligaments at the top of the
vagina and sutured inferiorly to the superficial transverse perinei
muscle. |
When the rectovaginal fascia is severely
torn or almost nonexistent, an autologous graft of fascia lata
or rectus fascia is sutured to the uterosacral ligaments, the rectovaginal
fascia overlying the levator ani, and the superficial transverse
perinei muscle creating a new "rectovaginal fascia." |
The vagina is then closed over this
repair leaving the tail of the suture marked "a" a
rather long piece of the suture. Note the denuded aponeurosis of
the bulbocavernosus in the midline. It is necessary to reapproximate
it with interrupted sutures if it is not intact. Do not trim or
over trim the vaginal mucosa before closing as this may lead to
narrowing of vaginal tube and dyspareunia. |
The suture line in the posterior vaginal
wall is brought down to the hymeneal ring. Suture "a" is
attached to the top of the vagina. Suture "b" is
at the hymeneal ring. Suture "a" is tied
to suture "b" and
suture "a" is trimmed. |
The perineal body is repaired by a
subcuticular stitch with suture "b" from the
hymeneal ring down to the anus. |
The complete repair is shown. A vaginal
exam should be performed to assure adequate width of the vagina
remains, and a rectal exam should be performed to ensure there
are no sutures in the rectum. |
When sutures "a" and "b" from
figure 12 are tied, the apex of the vagina is pulled down to the
stumps of the uterosacral ligaments leaving a more normal anatomical
position of the vagina by pulling it posteriorly. |
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