Residency · Residency · General Surgery
Rectal Prolapse and Pelvic Floor Disorders
Rectal Prolapse
Types
Full-thickness (complete) rectal prolapse, also known as procidentia, occurs when all layers of the rectal wall protrude through the anal canal. Mucosal prolapse involves only the mucosa and is distinguished from full-thickness prolapse by the presence of radial folds (mucosal) versus concentric rings (full-thickness). Internal rectal prolapse, or intussusception, occurs when the rectal wall intussuscepts but does not protrude beyond the anal verge.
Epidemiology
Rectal prolapse has a strong female predominance at a 6:1 ratio, with peak incidence in the seventh decade of life. Risk factors include chronic straining, multiparity, connective tissue disorders, neurologic conditions, and prior pelvic surgery. Rectal prolapse is often associated with other pelvic floor disorders such as rectocele, cystocele, and uterine prolapse.
Clinical Presentation
Patients present with visible protrusion with straining or spontaneously, along with mucous discharge, bleeding, fecal incontinence (affecting 50-75% of patients), and constipation or obstructed defecation (30-50%). It is important to distinguish rectal prolapse from prolapsing hemorrhoids: concentric mucosal rings indicate prolapse, whereas radial folds indicate hemorrhoids.
Evaluation
Physical examination with the patient straining, ideally sitting on a toilet if needed to demonstrate the prolapse, is the cornerstone of diagnosis. Colonoscopy should be performed to rule out a lead point lesion. Defecography, either fluoroscopic or MR defecography, is used to evaluate occult prolapse, rectocele, or enterocele. Anorectal manometry assesses sphincter function and helps guide the choice of operative approach. Pudendal nerve terminal motor latency testing provides prognostic information regarding continence recovery.
<image>Clinical photograph comparing full-thickness rectal prolapse with concentric mucosal folds versus prolapsing hemorrhoids with radial mucosal folds</image>
Surgical Approaches
Abdominal Approaches
Ventral mesh rectopexy is performed laparoscopically or robotically. Mesh is placed on the anterior rectal wall and secured to the sacral promontory. No posterior mobilization is performed, making this a nerve-sparing technique. It addresses prolapse as well as anterior compartment defects such as rectocele and enterocele. Recurrence rates are low at 5-10%, and it preserves continence and defecatory function. It has become the preferred abdominal approach in many European centers, though mesh complications including erosion and infection, while rare, must be discussed with the patient.
Posterior mesh rectopexy (Wells procedure) places mesh posteriorly between the rectum and sacrum. It has higher constipation rates compared to ventral mesh rectopexy and has been largely replaced by the ventral approach.
Suture rectopexy involves fixation of the rectum to the sacrum with sutures alone, avoiding mesh-related complications but carrying a higher recurrence rate than mesh-based approaches.
Resection rectopexy (Frykman-Goldberg) combines sigmoid resection with suture rectopexy. It is indicated for prolapse with significant redundant sigmoid and constipation and addresses constipation better than rectopexy alone, though it carries a risk of anastomotic leak.
Perineal Approaches
The Altemeier procedure (perineal rectosigmoidectomy) involves full-thickness resection of the prolapsed rectum via a perineal approach with a coloanal anastomosis performed at the dentate line. It is often combined with levatorplasty, which involves anterior plication of the levator muscles. It can be performed under regional or local anesthesia. Although it has higher recurrence rates than abdominal approaches at 10-30%, it is best suited for elderly or high-risk patients who are unfit for abdominal surgery.
The Delorme procedure involves mucosal sleeve resection with plication of the denuded muscular wall. It is less invasive than the Altemeier and is best for short prolapse (less than 3-4 cm) or mucosal prolapse. It has a higher recurrence rate than the Altemeier at 15-40% but can be repeated.
Choice of Approach
Fit patients are generally best served by an abdominal approach, such as laparoscopic ventral mesh rectopexy or resection rectopexy, which offers lower recurrence. High-risk or elderly patients benefit from a perineal approach, such as the Altemeier with levatorplasty, which carries lower morbidity. Short or mucosal prolapse is appropriate for the Delorme procedure. Prolapse with constipation and a redundant sigmoid is best addressed with resection rectopexy. When prolapse is accompanied by significant incontinence, ventral mesh rectopexy or Altemeier with levatorplasty is appropriate, and sphincter function may improve after prolapse repair.
<image>Surgical diagram comparing the Altemeier perineal rectosigmoidectomy with the laparoscopic ventral mesh rectopexy showing the different approaches and tissue planes</image>
Internal Rectal Prolapse (Intussusception)
Internal rectal prolapse involves intussusception of the rectal wall without external protrusion and causes obstructed defecation. It is diagnosed on defecography or MR defecography. Management begins with conservative measures including biofeedback, pelvic floor therapy, and dietary modification. Surgery is reserved for refractory cases and includes ventral mesh rectopexy. The STARR procedure (stapled transanal rectal resection) has largely fallen out of favor due to complications.
Rectocele
Definition and Pathophysiology
A rectocele is a herniation of the anterior rectal wall into the posterior vaginal wall. It is often asymptomatic, and its clinical significance depends on size and associated symptoms, which include sensation of incomplete evacuation, need to digitally support the posterior vaginal wall ("splinting"), and constipation.
Evaluation
Physical examination reveals a bulge in the posterior vaginal wall with straining. Defecography or MR defecography quantifies the size and functional significance by demonstrating contrast trapping.
Management
Conservative management includes dietary modification, pelvic floor physical therapy, and biofeedback. Surgical options for symptomatic, refractory cases include transanal repair with plication of the anterior rectal wall musculature, transvaginal repair (posterior colporrhaphy, often performed by gynecology), transperineal repair, and laparoscopic ventral mesh rectopexy (which addresses rectocele and internal prolapse simultaneously). Mesh should be avoided in transvaginal repairs due to high erosion rates, as reflected in an FDA warning.
Solitary Rectal Ulcer Syndrome (SRUS)
Solitary rectal ulcer syndrome is a chronic benign condition associated with internal prolapse, excessive straining, and direct trauma. Patients present with rectal bleeding, mucous discharge, and tenesmus. Endoscopy reveals shallow ulcers on the anterior rectal wall, typically 7-10 cm from the anal verge, which may be mistaken for malignancy. Histology shows fibromuscular obliteration of the lamina propria. Management is primarily conservative with biofeedback and avoidance of straining. Surgery, specifically rectopexy, is reserved for refractory cases with associated prolapse.
Pelvic Floor Dysfunction and Obstructed Defecation
Pelvic Organ Prolapse
Pelvic organ prolapse often involves multiple compartments: anterior (cystocele), middle (uterine or vaginal vault prolapse), and posterior (rectocele, enterocele). A multidisciplinary approach involving urogynecology, colorectal surgery, and pelvic floor physical therapy is essential. Laparoscopic sacrocolpopexy is the gold standard for vaginal vault prolapse.
Dyssynergic Defecation (Anismus)
Dyssynergic defecation involves paradoxical contraction or failure to relax the puborectalis and external sphincter during defecation. It is diagnosed by anorectal manometry and balloon expulsion testing. The mainstay of treatment is biofeedback therapy, which has a success rate of approximately 70%. Botulinum toxin injection into the puborectalis has limited evidence.
Descending Perineum Syndrome
Descending perineum syndrome is defined by excessive descent of the perineum during straining, more than 3 cm below the pubococcygeal line. It is often associated with chronic straining, pudendal neuropathy, and fecal incontinence. Management is conservative with pelvic floor physical therapy and avoidance of straining, as surgical results are generally poor.
<image>MR defecography images showing normal defecation compared to obstructed defecation with rectocele, enterocele, and internal rectal intussusception</image>
Fecal Incontinence
Etiology
The most common cause of fecal incontinence in women is obstetric sphincter injury. Other causes include surgical injury (from fistula surgery, hemorrhoidectomy, or sphincterotomy), neurologic conditions (pudendal neuropathy, spinal cord injury, diabetes), rectal prolapse, and age-related sphincter degeneration.
Evaluation
Evaluation begins with a detailed history using an incontinence scoring system such as the Wexner/Cleveland Clinic score. Endoanal ultrasound visualizes sphincter defects, anorectal manometry assesses resting and squeeze pressures, and MRI evaluates sphincter anatomy and muscle atrophy.
Management
Conservative management, which is the first line, includes dietary modification with fiber, pelvic floor physical therapy, and biofeedback. Medical management includes loperamide and fiber supplementation. Among minimally invasive options, sacral nerve stimulation (SNS/InterStim) is the first-line surgical therapy, involving test stimulation followed by permanent implant placement, with a 70-80% response rate. Posterior tibial nerve stimulation (PTNS) is an office-based alternative but is less effective than SNS. Injectable bulking agents provide modest benefit through submucosal injection into the anal canal. Surgical options include sphincteroplasty, an overlapping repair of the disrupted external sphincter that is best for discrete obstetric injury though results deteriorate over time, and the artificial bowel sphincter, which is rarely used due to high complication rates from infection and erosion. Dynamic graciloplasty, involving gracilis muscle transposition around the anal canal with chronic stimulation, is rarely performed. Colostomy is the last resort for severe refractory incontinence.
Clinical Pearls
The patient should always be asked to strain, ideally while sitting, to demonstrate prolapse, as it may not be evident in the supine position. The distinction between concentric folds (rectal prolapse) and radial folds (hemorrhoids) is critical. Fecal incontinence often improves after rectal prolapse repair, and continence outcomes are better with abdominal approaches. Ventral mesh rectopexy has become the preferred abdominal approach due to its nerve-sparing technique and favorable functional outcomes. Perineal approaches such as the Altemeier and Delorme procedures are ideal for high-risk patients who cannot tolerate general anesthesia or abdominal surgery. Biofeedback is first-line for dyssynergic defecation and should be attempted before surgical intervention. Sacral nerve stimulation has largely replaced sphincteroplasty as the first-line surgical treatment for fecal incontinence.
References
- Bordeianou L, et al. The American Society of Colon and Rectal Surgeons clinical practice guidelines for the treatment of rectal prolapse. Dis Colon Rectum. 2017;60(11):1121-1131.
- D'Hoore A, et al. Long-term outcome of laparoscopic ventral rectopexy for total rectal prolapse. Br J Surg. 2004;91(11):1500-1505.
- Paquette IM, et al. The American Society of Colon and Rectal Surgeons clinical practice guideline for the evaluation and management of fecal incontinence. Dis Colon Rectum. 2015;58(7):623-636.
- Tou S, et al. Surgery for complete rectal prolapse in adults. Cochrane Database Syst Rev. 2015;(11):CD001758.
- Rao SS. Dyssynergic defecation and biofeedback therapy. Gastroenterol Clin North Am. 2008;37(3):569-586.
