In the United States, 11% of women up to the age of 80 years have surgery for pelvic organ prolapse or urinary incontinence, and nearly one-third of procedures are repeat surgery (3). Data from the Women’s Health Initiative revealed anterior pelvic organ prolapse in 34.3%, posterior wall prolapse in 18.6%, and uterine prolapse in 14.3% of women in the study (7). In this study, a significant risk factor associated with prolapse was vaginal delivery. After adjusting for age, ethnicity, and body mass index, women with at least one vaginal delivery were twice as likely as nulliparous women to have pelvic organ prolapse. Causes of pelvic support disorders are most likely multifactorial, however; factors other than vaginal delivery also are associated with the development of these disorders. One study found that the incidence of prolapse doubled with each decade of life between the ages of 20 and 59 years (8). In another study, each year of increasing age was associated with a 12% increase in the risk of developing prolapse (9). Other associated risk factors for the development of POP include history of hysterectomy (8), obesity (7,10,11), history of previous prolapse operations, and race (11).
Pelvic organ prolapse results from attenuation of the supportive structures, whether by actual tears or “breaks” or by neuromuscular dysfunction or both. Support of the vaginal canal is provided by the enveloping endopelvic connective tissue and its condensations at the vaginal apex, which form the cardinal uterosacral ligament complex. The endopelvic connective tissue is the first line of support, buttressed intimately with the pelvic diaphragm, composed of the levator ani and coccygeus muscles. These muscles provide a supportive diaphragm through which the urethra, vagina, and rectum egress (Fig. 27.1). The muscular support provides basal tonicity and support of the pelvic structures; when contracted, as in the setting of increased abdominal pressure, the rectum, vagina, and urethra are pulled anteriorly toward the pubis.
The support system for the uterus and vagina has been described as consisting of three levels (12).
Level I refers to the uterosacral/cardinal ligament complex, which serve to maintain the vaginal length and axis.
Level II support consists of the paravaginal attachments of the lateral vagina and endopelvic fascia to the arcus tendineus that maintain the midline position of the vagina.
Level III support pertains to the distal vagina and is made up of the muscles and connective tissue surrounding the distal vagina and perineum.
Definitions The more common pelvic support disorders include rectoceles and cystoceles (Fig. 27.2), enteroceles (Fig. 27.3), and uterine prolapse (Fig. 27.4); reﬂecting displacement of the rectum, small bowel, bladder, and uterus, respectively; resulting from failure of the endopelvic connective tissue, levator ani muscular support, or both (12).
A rectocele is a protrusion of the rectum into the vaginal lumen resulting from weakness in the muscular wall of the rectum and the paravaginal musculoconnective tissue, which holds the rectum in place posteriorly.
An enterocele is a herniation of the peritoneum and small bowel and is the only true hernia among the pelvic support disorders. Most enteroceles occur downward between the uterosacral ligaments and the rectovaginal space, but they may also occur primarily apically, especially in the setting of a previous hysterectomy.
A cystocele is descent of the urinary bladder with the anterior vaginal wall. Cystoceles usually occur when the pubocervical musculoconnective tissue weakens midline or detaches from its lateral or superior connecting points.