Posterior compartment prolapse is often caused by a defect in the rectovaginal septum, also known as Denonvillier’s fascia. Patients with symptomatic posterior compartment prolapse can present with bulge symptoms as well as defecatory dysfunction, including constipation, tenesmus, splinting, and fecal incontinence. The diagnosis can successfully be made on clinical examination. Treatment of posterior prolapse includes pessaries and surgery. Both traditional colporrhaphy and site-specific defect repair have excellent success rates. Complications from surgery can include sexual dysfunction, de novo dyspareunia, and defecatory dysfunction. Compared with native tissue repair, biological and synthetic grafting has not improved overall anatomic and subjective outcomes.
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Symptomatic women of posterior compartment prolapse may present with complaints of vaginal bulge, constipation, tenesmus, splinting, and fecal incontinence.
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A clinical examination is generally sufficient in the workup of posterior compartment prolapse, and imaging studies should be reserved for cases whereby symptoms do not correlate with the physical examination.
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Defecatory dysfunction, quality of life, and sexual function can significantly improve after surgical repair with either traditional or site-specific colporrhaphy.
Introduction
In 2010 an estimated 166,000 women underwent surgical repair for pelvic organ prolapse. Of these women, an estimated 52% had a rectocele procedure as part of their repair. In women undergoing rectocele repair, the most common presenting symptoms beyond vaginal bulge are those of defecatory dysfunction, including constipation (46%), tenesmus (32%), splinting (39%), and fecal incontinence (13%). In addition, dyspareunia is present in 29%. Although the symptoms of posterior vaginal prolapse do not directly correlate with the degree of the prolapse, repair of a rectocele alleviates the associated symptoms in most patients.
Workup
Clinical Examination
The pelvic examination is performed in the dorsal lithotomy position. The posterior wall is assessed while supporting the vaginal apex and anterior wall with a separated posterior blade of a bivalve speculum. The authors currently use the Pelvic Organ Quantification System (POPQ) to objectively measure prolapse during maximal Valsalva effort ( Fig. 1 ). The POPQ system has been adopted by the American Urogynecologic Society, Society of Gynecologic Surgeons, International Urogynecological Association, and International Continence Society.
The POPQ measurements Ap and Bp measure the posterior vaginal wall. Point Ap is located in the midline of the posterior vaginal wall, 3 cm proximal to the posterior hymen. The quantitative value of point Ap is anywhere from −3 to +3 cm from the hymeneal ring, depending on the extent of posterior wall prolapse. Point Bp is the most distal (ie, most dependent) position of any part of the upper posterior vaginal wall between point Ap and the vaginal cuff or posterior vaginal fornix. This value can range from −3 (no prolapse) to more than +3 (up to the total vaginal length) if associated with a vault prolapse beyond the hymeneal ring.
A rectal examination aids in detecting specific defects in the posterior vaginal wall and can help identify an enterocele or sigmoidocele. In addition, one can evaluate for an enterocele by evaluating the patient in a standing position because the small bowel will enter the enterocele sac. It is also important to evaluate for rectal intussusception or rectal prolapse. In addition, a rectal examination can help evaluate the integrity of the perineal body and anal sphincter tone.
Imaging
A thorough clinical examination is an accurate way of evaluating for posterior compartment defects. Imaging studies are occasionally useful if there is a concern for other abnormality, or if there is recurrent posterior compartment prolapse. The use of ancillary studies may also be helpful for patients who complain of fecal incontinence or report defecatory dysfunction and do not have a posterior compartment prolapse on clinical examination.
Defecography
Defecography provides a 2-dimensional view of rectal emptying efficiency and allows for the quantification of rectal measurements. The size of the rectocele is determined by measuring the distance between the anterior border of the anal canal and the maximal point of the bulge of the rectal wall into the posterior vaginal wall. Anything less than 2 cm is considered normal, and a rectocele is considered large if the rectal wall protrudes more than 3.5 cm. The clinical utility of defecography is limited, and diagnosis of anterior rectocele correlates with level of experience of the person reading the test. One study of elderly patients found no association between abnormalities found on defecogram and symptoms. Another suggested only a limited correlation between the radiologic findings and clinical outcomes after surgical repair. The authors do not typically obtain defecography studies unless they are considering a diagnosis of pelvic floor dyssynergia, whereby the puborectalis or external anal sphincter muscle is paradoxically contracted on rectal examination, or identifying a sigmoidocele.
Magnetic Resonance Imaging
Dynamic magnetic resonance imaging (MRI) offers high-quality images of the pelvic soft tissues and viscera, and can be used to evaluate posterior compartment prolapse. However, the lack of standardization in grading posterior prolapse, the high cost of MRI, and its poor correlation with clinical staging makes its routine use problematic. MRI does continue to be used in the research setting. Because clinical examination has a high sensitivity for detecting rectoceles, the authors generally do not order MRI for the routine evaluation of posterior compartment prolapse.
Endoanal Ultrasonography
On clinical examination, diminished resting or squeeze tone of the distal anal canal and suspicion of a sphincter disruption may prompt an endoanal ultrasonogram. This modality can aid in the detection of a sphincter defect (either internal or external), and also allows visualization of the puborectalis muscle. The finding of a defect in the sphincter complex in an appropriate patient with complaints of fecal incontinence may prompt consideration of a sphincteroplasty.
Workup
Clinical Examination
The pelvic examination is performed in the dorsal lithotomy position. The posterior wall is assessed while supporting the vaginal apex and anterior wall with a separated posterior blade of a bivalve speculum. The authors currently use the Pelvic Organ Quantification System (POPQ) to objectively measure prolapse during maximal Valsalva effort ( Fig. 1 ). The POPQ system has been adopted by the American Urogynecologic Society, Society of Gynecologic Surgeons, International Urogynecological Association, and International Continence Society.
The POPQ measurements Ap and Bp measure the posterior vaginal wall. Point Ap is located in the midline of the posterior vaginal wall, 3 cm proximal to the posterior hymen. The quantitative value of point Ap is anywhere from −3 to +3 cm from the hymeneal ring, depending on the extent of posterior wall prolapse. Point Bp is the most distal (ie, most dependent) position of any part of the upper posterior vaginal wall between point Ap and the vaginal cuff or posterior vaginal fornix. This value can range from −3 (no prolapse) to more than +3 (up to the total vaginal length) if associated with a vault prolapse beyond the hymeneal ring.
A rectal examination aids in detecting specific defects in the posterior vaginal wall and can help identify an enterocele or sigmoidocele. In addition, one can evaluate for an enterocele by evaluating the patient in a standing position because the small bowel will enter the enterocele sac. It is also important to evaluate for rectal intussusception or rectal prolapse. In addition, a rectal examination can help evaluate the integrity of the perineal body and anal sphincter tone.
Imaging
A thorough clinical examination is an accurate way of evaluating for posterior compartment defects. Imaging studies are occasionally useful if there is a concern for other abnormality, or if there is recurrent posterior compartment prolapse. The use of ancillary studies may also be helpful for patients who complain of fecal incontinence or report defecatory dysfunction and do not have a posterior compartment prolapse on clinical examination.
Defecography
Defecography provides a 2-dimensional view of rectal emptying efficiency and allows for the quantification of rectal measurements. The size of the rectocele is determined by measuring the distance between the anterior border of the anal canal and the maximal point of the bulge of the rectal wall into the posterior vaginal wall. Anything less than 2 cm is considered normal, and a rectocele is considered large if the rectal wall protrudes more than 3.5 cm. The clinical utility of defecography is limited, and diagnosis of anterior rectocele correlates with level of experience of the person reading the test. One study of elderly patients found no association between abnormalities found on defecogram and symptoms. Another suggested only a limited correlation between the radiologic findings and clinical outcomes after surgical repair. The authors do not typically obtain defecography studies unless they are considering a diagnosis of pelvic floor dyssynergia, whereby the puborectalis or external anal sphincter muscle is paradoxically contracted on rectal examination, or identifying a sigmoidocele.
Magnetic Resonance Imaging
Dynamic magnetic resonance imaging (MRI) offers high-quality images of the pelvic soft tissues and viscera, and can be used to evaluate posterior compartment prolapse. However, the lack of standardization in grading posterior prolapse, the high cost of MRI, and its poor correlation with clinical staging makes its routine use problematic. MRI does continue to be used in the research setting. Because clinical examination has a high sensitivity for detecting rectoceles, the authors generally do not order MRI for the routine evaluation of posterior compartment prolapse.
Endoanal Ultrasonography
On clinical examination, diminished resting or squeeze tone of the distal anal canal and suspicion of a sphincter disruption may prompt an endoanal ultrasonogram. This modality can aid in the detection of a sphincter defect (either internal or external), and also allows visualization of the puborectalis muscle. The finding of a defect in the sphincter complex in an appropriate patient with complaints of fecal incontinence may prompt consideration of a sphincteroplasty.
Treatment
Treatment should be pursued only if the patient’s prolapse is symptomatic. She should be counseled regarding potential outcomes with expectant management and pessary use. Pessary fittings have been found to be successful in the treatment of symptomatic pelvic organ prolapse. In one study of 100 consecutive patients with symptomatic pelvic organ prolapse, pessaries were successfully fitted in 73% of patients, with 92% still being satisfied at a 2-month follow-up. Patients successfully fitted with pessaries noted significant decreases in vaginal bulge (90% down to 3%; P <.001), pressure (49% down to 3%; P <.001), and splinting to defecate (14% down to 0%; P = .001). The authors offer virtually all of their patients a pessary trial before discussing the possibilities of surgical treatment.
Posterior Colporrhaphy
The goal of posterior transvaginal repair is to relieve symptoms relevant to the anatomic support defect. Patients often present with complaints of a vaginal bulge or obstructed defecation. In plicating the endopelvic fascia (also known as the Denonvillier fascia), the strength of the posterior vaginal wall is increased, eliminating the vaginal bulge and allowing for better stool emptying. The surgical technique of traditional posterior colporrhaphy has been previously reviewed in this journal. In brief, a small diamond-shaped incision is made from the perineum to the posterior vaginal mucosa beyond the hymen after injection of a hemostatic solution, and the skin is excised. The posterior vaginal mucosa is undermined and a midline incision is made past the apex of the rectocele. The posterior vaginal epithelium is then dissected in a thin plane off of the Denonvillier fascia, with the dissection carried laterally to the levator muscles. Plication of the edges of the Denonvillier fascia over the herniated rectum is performed with interrupted stitches of 2-0 delayed absorbable sutures (the authors use 2-0 Vicryl) from the upper edge of the rectocele to the perineal body. The vaginal epithelium is trimmed if necessary and then closed to the hymen with a running 2-0 delayed absorbable suture. Perineorrhaphy is performed as appropriate, and the reconstructed rectovaginal septum is attached to the reconstructed perineal body. The rest of the vaginal and perineal skin is then closed.
Perineorrhaphy
A perineorrhaphy is often necessary when treating posterior compartment prolapse. The rectovaginal fascia normally attaches to the perineal body, although detachment is often seen in women with posterior compartment defects. Compromise of this attachment can lead to perineal descent and a relaxed perineum. During a perineorrhaphy, the bulbocavernosus and transverse perinei muscles are brought together in the midline of the perineal body with absorbable sutures. The authors typically also attach the reconstructed rectovaginal septum to the reconstructed perineal body. A well-performed perineorrhaphy helps prevent perineal descent with bowel movements, and reduces the need for defecatory splinting. Although vaginal dimensions did not predict dyspareunia in a study of sexually active women undergoing posterior repair, care should be taken to avoid an overaggressive perineorrhaphy, which can constrict the vaginal opening and lead to dyspareunia.
Endorectal Repair
Colorectal surgeons typically approach posterior compartment defects through a transanal approach. The first endorectal rectocele repair was described in 1968 by Sullivan and colleagues. An endorectal repair is done with the patient in the prone jack-knife position. An anal retractor is inserted to expose the anterior rectal wall. Two transverse incisions are made; the first is in the rectal mucosa at or near the dentate line and the second is made cephalad, above the prolapsed defect. One vertical incision is made in the midline. Mucomuscular flaps are developed on each side of the vertical incision. The rectovaginal septum is reapproximated using vertical plication sutures with a 3-0 polyglycolic acid suture. The rectal flaps are trimmed and the incision is closed with a running 5-0 polyglycolic acid suture. (Adapted from Khubchandani and colleagues. )
Posterior Colporrhaphy Versus Endorectal Repair
Colorectal and gynecologic surgeons traditionally perform rectocele repairs using different surgical approaches (transanal and transvaginal, respectively). The disadvantages of a transanal approach include the inability to repair prolapse in other vaginal compartments concurrently, limited exposure, the inability to access high rectoceles and enteroceles, and a possible increased risk of rectovaginal fistula formation. An advantage of a transanal approach is the ability to perform concurrent rectal procedures in the same positioning. Early retrospective reviews suggested that the transanal and transvaginal approaches have similar symptomatic outcomes and complication rates. However, more recent evidence suggests that the transanal approach is not durable, with a 50% anatomic recurrence rate at a mean 6 years of follow-up: much higher than in series of transvaginal repairs. In addition, there are concerns of decreased anal sphincter integrity following anal retraction, which may lead to de novo fecal incontinence. To date, one randomized controlled trial of transvaginal versus transanal rectocele repair has been performed. At 1-year follow-up, improved anatomic outcomes were seen in the transvaginal group compared with the transanal group (7% rectocele recurrence compared with 40% rectocele recurrence, respectively). In addition, enteroceles and flatal incontinence were each present in 27% of the transanal repair group, whereas no patients in the transvaginal group had these problems. Improvement in symptoms was also better in the transvaginal group (93% vs 73%).
More recently a newer transanal repair technique has been introduced, the stapled transanal rectal resection (STARR procedure). This technique has the purported advantages of decreased operative time and blood loss while being able to treat rectal intussusception, if present. However, it is limited by increases in patient morbidity. In a large registry (n = 379) of patients undergoing the STARR procedure, complications included 3% bleeding requiring reoperation, 2% anal stenosis requiring dilatation, 3% fecal incontinence, and 2 reports of rectal injury and sepsis requiring fecal diversion.
Site-Specific Defect Repair
The rationale for a site-specific rectocele repair is based on the theory that herniation of the rectum into the vagina results from specific tears in the rectovaginal fascia. These injuries may occur as an isolated defect in the lateral, distal, midline, or superior portions of the vaginal wall, or as a combination of defects ( Fig. 2 ). During repair of site-specific defects, the posterior vaginal epithelium is incised to the rectocele bulge and the vaginal mucosa is dissected from the underlying Denonvillier fascia all the way to the arcus tendineus on each side. A finger is then placed into the rectum to identify specific fascial defects, which are repaired with interrupted absorbable sutures. Any perineal defects are then corrected in the standard fashion, before skin closure.
