PROLAPSE
Prolapse is defined as any descent of the uterus down the vaginal canal, so that it lies below the normal position in the pelvis. In the extreme, this may result in the uterus descending beyond the vulva to a position outside the body (procidentia). Some degree of uterine descent is common in parous women.
The etiology and mechanism of a descensus of the uterus are fundamentally
the same as those associated with retrodisplacement or the formation of a
cystocele, enterocele, or rectocele: Loss of normal structural support as a
result of trauma (childbirth), surgery, chronic intraabdominal pressure
elevation (such as obesity, chronic cough, or heavy lifting), or intrinsic
weakness. The most common sites of injury are the cardinal and uterosacral
ligaments and the levatorani muscles that form the pelvic floor, which may relax
or rupture. Rarely, increased intraabdominal pressure from a pelvic mass or
ascites may weaken pelvic support and result in prolapse. Injury to or
neuropathy of the S1 to S4 nerve roots may also result in decreased muscle tone
and pelvic relaxation.
Retroversion of at least second degree is almost always concurrently
present, as explained by plainly mechanical reasons: intraabdominal pressure
forces the uterus directly downward, stretching all three sets of pelvic
supporting structures, when the uterus, with the patient upright, is in a
vertical or backward position.
Descent that does not involve protrusion of the cervix at the introitus
is known as first-degree or second-degree prolapse based upon the distance
toward the introitus. When only the cervix reaches the introitus or slightly
protrudes, third-degree prolapse is present. If the entire uterus is pushed
outside the introitus, a complete procidentia (fourth-degree prolapse in some
numbering schemes) exists.
Because of the intimate association of the bladder with the cervix,
prolapse of the uterus generally draws down the bladder and produces an
accompanying cystocele. The laxity of structures constituting the pelvic floor,
not being restricted to the uterovesical relations, leads to complete asthenia
of the pelvic outlet, so that rectocele also is a frequent complication of
prolapse. Enterocele is always present in procidentia, where the cul-de-sac of
Douglas is brought down with the uterus and frequently contains loops of
intestine or omental tabs. Because of chafing and irritation of the exteriorized
cervix, ulcerations and erosions frequently occur. Surprisingly, cervix
carcinoma is an uncommon finding in such irritated areas.
Prolapse may be associated with multiple complaints, ranging from
functional bleeding and backache to the more common “heavy” or “bearing-down”
feeling in the pelvis, urinary difficulties, and constipation. There may also be
new-onset or paradoxical resolution of urinary incontinence. Each of these
symptoms must be evaluated in the light of experience and judgment before
attempting surgical correction. The patient’s age, desire for fertility, and personal preferences should all enter into
the equation in deciding upon correct management. It should be kept in mind
that retroversion by itself is almost never a decisive factor in clinical
complaints, that most backaches are due to reasons other than
retrodisplacement, and that incontinence and urinary frequency may disappear
following treatment of underlying urinary tract diseases. Surgical or pessary
therapy may even make some symptoms (such as urinary incontinence) worse.
With these factors well in mind, the surgeon has a wide variety of procedures at his or her disposal to suspend the uterus, bladder, and vesicle neck and repair the pelvic diaphragm. Minimal prolapse does not require therapy. For those with more severe prolapse or symptoms, pessary therapy, surgical repair, or hysterectomy (with colporrhaphy) should be considered. Postmenopausal women should receive estrogen and progesterone replacement therapy for at least 30 days before pessary fitting or surgical repair.
