Figure 70-21. Endorectal advancement of anorectal flap. A: Exposure is gained by an anal speculum, and the fistula is identified.

Outline of endorectal flap, extending proximally to 7 cm from the anal verge. B: The full-thickness flap is created to include the

internal sphincter muscle. C: Lateral mobilization is made on each side in the submucosal plane. D: Anorectal wall on each side is

approximated. E and F: The endorectal flap is pulled down to cover the wound and sutured. The fistula is excised. The aperture in

the vagina is not sutured but is left open for drainage.

As excision often leads to a large defect, numerous flap closures have been described for pilonidal

disease. These include a rhomboid rotational flap, gluteus maximus rotational flap, z-plasty, and an

advancement flap of skin and gluteal fat (Karydakis flap).25 Excellent results have been reported from

specialty centers using these approaches.

The Bascom procedure is based on the premise of removing the pilonidal disease while avoiding

excision of large areas of normal tissue. This involves making a vertical incision at least 1 cm off the

midline overlying the chronic cavity, without excising the walls of the cavity. The sinus tracts leading to

the midline pits are probed and curetted to remove any granulation tissue. The midline pits are then

excised and closed, while the lateral incision is left to close by secondary intention. Excellent results

have been reported with this procedure,26 however, no trials comparing this to other techniques have

been published.

Rectal Prolapse

4 Rectal prolapse (procidentia) is a relatively uncommon condition in which there is a full-thickness

protrusion of the rectum through the anal canal. A related condition is rectal intussusception, which is

where the rectum telescopes into itself but not through the anus. Rectal prolapse is significantly more

common in females than in males, and many patients have a long standing history of straining and

constipation. Association with other pelvic floor conditions such as urinary incontinence, voiding

disorders, and cystoceles is common. Prolapse is also more commonly found in patients with dementia,

mental retardation, and schizophrenia.

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Pathophysiology

The exact cause of rectal prolapse is not known, however it likely represents chronic progression of

intussusception. As the rectum or rectosigmoid infolds onto itself, it progressively pulls the rectal wall

away from its attachments to the sacrum and pelvic sidewall. With persistent straining, the bowel

continues to intussuscept, eventually leading the entire wall of the rectum to evert through the anal

opening. Studies of anorectal function in patients with rectal prolapse demonstrate that these patients

often have impaired resting and voluntary squeeze pressures in the anal sphincter, decreased rectal

capacity, impaired continence, and inadequate puborectalis relaxation during defecation. Incontinence is

likely secondary to chronic mechanical stretching of the sphincters from the prolapse, stretch injury to

the pudendal nerves, and loss of normal sensation of the anal canal. Several anatomic abnormalities are

typically seen in patients with chronic rectal prolapse ( Table 70-5), however, it is unclear whether

these are factors that lead to prolapse or whether they are caused by the condition.

ETIOLOGY

Table 70-5 Anatomic Abnormalities in Rectal Prolapse

Solitary rectal ulcer syndrome (SRUS) is a rare condition that is also likely related to intussusception

of the rectum. The straining from constipation can lead to an ulcer in the anterior rectal wall from

repeated mucosal trauma. In severe cases, SRUS may lead to gastrointestinal hemorrhage and chronic

pain. Biopsies of these ulcers often demonstrate mucosal glands displaced within the submucosa, which

may lead to the misdiagnosis of carcinoma.

Evaluation

The diagnosis of rectal prolapse is clinically made on the basis of the history and physical examination.

Patients typically present complaining of a mass with defecation that may or may not spontaneously

reduce. Prolapse is often associated with fecal or mucous soilage and pelvic discomfort; pain is not

typically present. Digital rectal examination often demonstrates a patulous anus with decreased

sphincter tone. Full-thickness rectal prolapse will appear as concentric rectal rings protruding through

the anus (Fig. 70-22). It is important to differentiate full-thickness prolapse from prolapsed hemorrhoids

or mucosal prolapse, which will appear as radial folds. If the prolapse is not obvious, it is best

demonstrated by asking the patient to strain while seated on a commode. Anoscopy or proctoscopy will

often show mildly inflamed mucosa or ulceration. Patients should be evaluated with a colonoscopy to

evaluate for bleeding and to rule out a mass, which can rarely serve as the lead point of intussusception.

For those patients with chronic constipation, a colonic transit study may help to determine whether

colonic resection may be necessary. Anal manometry is not typically useful other than to document

baseline function. When intussusception is suspected but cannot be visualized, defecography may be

helpful and may demonstrate other related conditions such as enterocele or puborectalis dyssynergy.

Patients with other pelvic floor complaints require further evaluation by urogynecology.

Management

Surgical intervention is the gold standard for treating full-thickness rectal prolapse, however

nonoperative management with treatment of the constipation and pelvic floor strengthening exercises

has been described in patients who are poor surgical candidates. While the objective is to resolve the

prolapse, repair may also help to improve or restore fecal continence and correct functional

constipation. Several different operations have been described for rectal prolapse, either from an

abdominal or perineal approach. The benefit of a perineal approach is that it can be performed under

regional anesthesia and generally is less painful that an abdominal approach. The perineal procedures

may be ideal for older patients or those individuals who may not tolerate general anesthesia or major

abdominal surgery. The trade-off is that the recurrence rates of a perineal approach are generally higher

(up to 38%) than an abdominal approach (less than 12%).27 Perineal repair of rectal prolapse includes

the Altemeier perineal rectosigmoidectomy and Delorme plication. Abdominal approaches include

rectopexy, with or without concomitant sigmoid colon resection.

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Figure 70-22. Full-thickness rectal prolapse will appear as concentric rectal rings protruding through the anus.

Perineal rectosigmoidectomy (Altemeier procedure) is a transanal surgery in which the prolapsed

rectum and redundant sigmoid colon are excised through the rectum. The procedure is typically

performed in the prone jack-knife position and can be performed under general or spinal anesthesia

(Fig. 70-23). The rectum and sigmoid colon are resected and a low anastomosis is performed just

proximal to the dentate line. Ideally a levator muscle imbrication and a colonic j-pouch are performed

prior to a stapled or hand-sewn anastomosis. The former maneuver may help improve continence while

the latter adjunct may help decrease bowel frequency. Without these steps, loss of the compliant rectum

combined with low resting anal sphincter pressures often results in incontinence, soiling, and urgency.

Major long-term complications include recurrence, fecal urgency, tenesmus, and anastomotic stricture.

Overall results vary, but there is some data to suggest that among the perineal approaches, the

Altemeier procedure has the lowest recurrence rates and best functional outcomes.28

The Delorme procedure is also typically performed in the prone position, and is useful in patients

whose rectum does not prolapse more than 5 cm. This procedure involves stripping the mucosa of the

prolapsed rectum from the muscularis propria, followed by plication of the muscularis propria and

reanastomosis of the mucosal ring (Fig. 70-24). This procedure may also be combined with

levatoroplasty or sphincter repair in an effort to improve functional outcomes. This technique has a high

recurrence rate but has very low associated morbidity, and may therefore be useful in frail, older

patients.

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