Posterior vaginal wall prolapse includes rectoceles, enteroceles, and sigmoidoceles and often occurs in combination with other pelvic support problems. Isolated rectoceles are quite rare. Figures 33-1 and 33-2 demonstrate an isolated rectocele.

Posterior Colporrhaphy

Posterior colporrhaphy, also known as transvaginal rectocele repair, refers to a variety of approaches, that is, the traditional posterior colporrhaphy with transverse midline plication of the rectovaginal fascia, with or without levator ani plication, and the site-specific posterior repair, either of which can include graft augmentation. Ultimately, the goal of rectocele repair is to improve prolapse symptoms, bowel function, and sexual function.

Patient Evaluation

The primary indication for performing a posterior colporrhaphy is symptomatic posterior compartment prolapse, which most commonly manifests as the sensation of a vaginal bulge. Outlet dysfunction constipation may also be present, causing stool trapping in the area where the rectum herniates into the vagina. In this scenario, patients may have to splint (place fingers inside the vagina or on the perineal body) in order to defecate. The symptoms of vaginal bulge and splinting are fairly specific for posterior compartment prolapse, and are the symptoms most likely to be cured by this procedure. Surgical repair of asymptomatic posterior vaginal prolapse is not recommended. Concurrent pelvic support defects are often present, and should be addressed concomitantly at the time of posterior compartment surgery.

By plicating the posterior vaginal muscularis or medial aspect of the levator ani muscles in the midline, the posterior vaginal wall width is decreased, the fibromuscularis in the midline is increased, and the vaginal tube is narrowed. A perineorrhaphy is typically included in this repair.

Consent

In general, anatomic cure rates are excellent,^1-3 with overall improvement in bowel symptoms, regardless of the type of repair. A recent randomized trial of 106 patients compared three surgical techniques of rectocele repair: traditional colporrhaphy, site-specific repair, and site-specific rectocele repair augmented with a porcine-derived, acellular collagen matrix graft (Fortagen^®).⁴

At one year after surgery, anatomic cure of prolapse (defined as < Stage 2) was comparable in the posterior colporrhaphy group (86%) and the site-specific group (78%). The cure rates of both traditional and site-specific rectocele repair groups were statistically significantly better than the graft-augmented site-specific repair (54%).

Posterior wall prolapse to or beyond the hymen developed in 20% in those who received graft augmentation, compared with 7.1% in the posterior colporrhaphy group and 7.4% in the site-specific repair group. Time to development of posterior vaginal wall prolapse was significantly earlier in the graft augmentation group compared with that in the traditional rectocele repair group. The site-specific group also developed recurrent prolapse earlier than the traditional posterior colporrhaphy group, but this was not statistically significant.

Functional failure (worsening of prolapse or colorectal symptoms one year after surgery) occurred in 16% of the posterior colporrhaphy group, 12% of the site-specific repair group, and 21% of the graft augmentation group. These differences were not statistically significant.

Defecatory dysfunction decreased significantly postoperatively, with no significant differences among treatment groups. At one year follow-up, the development of new-onset bowel dysfunction was uncommon (11%), with the cure of posterior vaginal prolapse at Stage 0 or 1 associated with the significant reduction of bothersome straining and incomplete emptying.⁵

The preoperative dyspareunia rate was 51%, and the postoperative dyspareunia rate was 36%, with no significant differences among the groups (20% in the posterior repair group, 14% in the site-specific group, and 6% in the graft augmentation group). The high preoperative dyspareunia rate may be due to the use of a validated sexual function questionnaire. There was improvement in sexual function after rectocele repair, regardless of the technique used.

In summary, anatomic and functional outcomes were not significantly different for the standard posterior colporrhaphy and site-specific repair groups, but were overall superior to the graft augmentation group. Bowel and sexual function and quality of life significantly improved in all three groups.

There may be a number of etiologies for the worse outcomes in the graft augmentation group. This particular graft may have impaired normal healing. Alternatively, the body may have perceived the graft as foreign material due to its cross-linking or if it was not completely acellular and still contained porcine DNA.

Patients should be counseled about the risk of de novo dyspareunia, which has been described especially after traditional posterior colporrhaphy and levator ani plication.^6,7 Other potential complications include posterior vaginal hematoma, infection, rectal injury, and nerve injury due to positioning of the legs.

If a graft (either synthetic or biologic) is used, patients should be carefully counseled that the use of mesh can lead to sequelae such as mesh erosion, dyspareunia, as well as pain. Given the FDA public health advisory on the use of transvaginal mesh kits in the use of prolapse,⁸ the counseling about these risks should be carefully documented in the medical record.⁹

The patient’s goals regarding the outcome of surgery should be discussed preoperatively in order to manage expectations, and avoid any disappointments postoperatively.

Surgical Steps

Anesthesia and Patient Positioning

Repair of posterior compartment prolapse can be performed under regional or general anesthesia, depending on the patient and surgeon’s preference. Many patients have prolapse in other compartments, as well as stress incontinence, which necessitates concomitant prolapse repair and anti-incontinence procedures that may guide the choice of anesthesia.

Preoperatively antibiotics should be administered intravenously, with either a first-generation cephalosporin such as cefazolin or a combination of gentamicin and clindamycin if the patient has a penicillin allergy. Deep venous thrombosis prophylaxis should also be applied, with either sequential compression stockings or subcutaneous administration of heparin or low-molecular-weight heparin, or a combination of both.

The patient is then placed in high dorsal lithotomy position, in either Allen (Allen Medical Systems, Acton, MA) or candy cane stirrups, ensuring that the hips and legs are not overly flexed or extended. Femoral neuropathy can result from overly flexed hips, while peroneal neuropathy may result from compression of the lateral aspect of the knees. Examination under anesthesia with both pelvic and rectal examinations should be performed. After surgical prepping and draping, a 16 French Foley catheter is placed in the bladder for drainage.

Vaginal Incision and Dissection