Rectal prolapse is a condition where the rectum turns itself inside out and protrudes
outside of the anus either a short or long distance (up to 6 inches or more). Rectal
prolapse usually occurs during bowel movements and although in many patients the
prolapse spontaneously returns back into the body after the BM, in advanced cases
it may remain outside. If stuck outside, external pressure may need to be applied
in order to push it back into the anus. When the prolapsed rectum is outside the
body it often causes pain and discomfort and can also make walking and moving difficult.
In patients who have had rectal prolapse for a long time the anal sphincter muscles
may become weak and this weakness usually results in leakage of stool and gas (fecal/gas
incontinence) may develop. Although it can be seen in men, it develops far more
often in women. For unclear reasons it can found both in women who have had many
children as well as those who have had no children. Patients with rectal prolapse
often seek surgical treatment.
There are two very different ways to surgically approach and repair rectal prolapse.
It can be repaired either via abdominal surgery or an operation done through the
anus (trans-anal). The abdominal operation is a bigger procedure that requires general
anesthesia, however, the rate of recurrence of the prolapse is notably lower (5-8%)
than with the “through the anus” method (15-30%). On the other hand, the trans-anal
method requires no external incisions at all (on abdomen or buttock) and can be
done under a spinal anesthetic with the patient breathing on their own. When the
trans-anal approach is used, in addition to removing the prolapsed rectum the anal
sphincter muscles are often tightened a bit (called a sphincteroplasty). It is important
to note that both methods are associated with an improvement in anal sphincter function
and control in 50 to 70 percent of patients. Each approach will be briefly discussed
below. Dr.Whelan performs both types of rectal prolapse repair.
There are a variety of ways to treat a rectal prolapse through the abdomen. This
article will not discuss or describe all of the methods. Suffice it to say that
all abdominal methods pull up the rectum, which is usually very long and sagging
into the pelvis, and anchor it to either the upper pelvis or some other part of
the abdomen. The attachment of the rectum or its supporting tissue to a surrounding
structure to prevent it from prolapsing is called a “rectopexy”. In theory, once
the rectum has been pulled up, via the rectopexy, it will not be able to prolapse
outside the anus. Unfortunately, in between 5 and 8 percent of patients, the prolapse
may return in the months and years that follow the surgery.
In order to perform the rectopexy the rectum must be “mobilized” from the tissues
surrounding it in the pelvis. The lower two thirds of the rectum is embedded in
the deep pelvic tissues. Before the rectum can be effectively pulled up and anchored
in the upper pelvis (closer to the head) it must be freed up from these attachments.
This mobilization process unfortunately cuts a number of small invisible nerves
that supply the rectum. Probably because of the loss of these small nerves is that
most patients have fewer bowel movements after the surgery. In a proportion of patients
noticeable constipation (there may be several days or more between BM’s) may develop.
In order to prevent or offset this effect of the rectopexy, many surgeons will also
resect and remove a piece of sigmoid colon (the next part of the large bowel after
the rectum when heading from the anus to the mouth). This is called a sigmoid resection.
About 15 to 25 cm of colon is removed when a sigmoid resection is done. When a colon
resection is performed there is a possibility that an anastomotic leak or abdominal
abscess may develop (in 1-3 %). All of the through the abdomen surgical approaches
for rectal prolapse require general anesthesia.
The most common through the anus approach involves resecting (removing) the part
of the rectum that protrudes from the anus. The rectum is surgically detached from
the anus and the anal sphincter (which are preserved) and then is resected. The
two remaining ends of the large bowel (the anus and the remaining rectum) are then
sewn together with absorbable sutures (that do not need to be removed). As mentioned,
the anal sphincter muscle is usually tightened with sutures (to, hopefully, improve
the anal sphincter strength) during this operation. This operation can be done under
a spinal anesthetic and does not require general anesthesia. Avoiding general anesthesia
is generally safer for patients who have cardiac, pulmonary, or other serious chronic
medical problems. Therefore, for older patients with multiple medical problems the
transanal approach is often advised or requested. Another advantage of this approach
is that there is little pain after surgery.
As mentioned, a good proportion of long standing rectal prolapse patients develop
anal sphincter muscle weakness which results in the symptoms of incontinence of
gas and/or stool. This is thought to occur because when rectal prolapse occurs it
stretches and can injure the pelvic nerves that supply the anal sphincter muscles.
Independent of stool control issues, the prolapsed rectum often leaks mucus, sometimes
blood tinged. Surgical repair of rectal prolapse restores sphincter strength in
50 to 70 percent of patients. Unfortunately, in 30 to 50 percent of patients the
sphincter weakness and stool control issues persist even after surgical repair.
Non-surgical treatments for anal muscle weakness include Kegel exercises, biofeedback
training (also to strengthen the anal muscles), and bulking of the stool (accidents
are less likely with formed or hard stool).
This is different than hemorrhoid prolapse where only the innermost 2 layers of
the rectum slide outside a short distance. In order for a rectal prolapse to form
the entire rectal wall must turn inside out and protrude from the anus.
Our family wishes to express our heartfelt appreciation for the kindness, excellent
care and wisdom our mother, Jean Broussard, received during her hospitalization.