The precise pathogenesis and etiology of rectal prolapse is still uncertain: Is it a sliding hernia, intussusception or a combination of both mechanisms? The clinical picture includes the following functional anatomical abnormalities to varying degrees:
- an abnormally deep Douglas pouch (3, 17, 24)
- Diastasis of the levator ani limbs
- Functional weakness of the inner and outer anal sphincters (3, 17)
- Weak pelvic floor muscles
- Pudendal neuropathy (17, 24)
- Mobile mesorectum with inadequate posterior and lateral fixation of the rectum (17, 24, 34)
- Elongated redundant sigmoid (17, 24, 34).
In the end, which of the changes favors rectal prolapse and which are sequelae is ultimately unclear and almost impossible to establish during diagnostic work-up.
Treatment aims to repair the prolapse and restore normal defecation and continence patterns. Treatment includes the following options (17, 24, 34):
- Rectal fixation to the sacrum
- Resection or plication of the redundant bowel.
Access classifies the procedures as transabdominal or local.
1. Transabdominal procedures (laparotomy, laparoscopy)
1.1 Rectopexy
The rectum is reattached to the presacral fascia, thereby repairing the inadequate suspension from the sacrum. Stretching the rectum relieves the load on the pelvic floor, which supposedly promotes recovery of the pelvic floor muscles. Rectopexy variants are the following:
1.1.1 Suture rectopexy
Sudeck (29) was the first to perform this procedure, which mobilizes the rectum down to the pelvic floor and secures it to the promontory with interrupted sutures. The presacral fibrosis induced by this mobilization supposedly helps to stabilize the rectal fixation. Recurrence rates of up to 10 % have been reported, and data on postoperative dysfunction vary considerably (21).
1.1.2 Rectopexy foreign material
Foreign material is intended to result in more extensive presacral fixation of the mobilized and stretched rectum. Depending on the position of the material, the procedure is either classified as Ripstein (anterior loop rectopexy) (27), Orr-Loygue (lateral fixation) or Wells procedure (posterior mesh rectopexy) (31). Another variant is anterior rectopexy, which assumes that mobilization of the rectum results in postoperative defecation disorders (23, 28): therefore, the rectum is mobilized only in the rectovaginal space and anchored to the promontory with a mesh attached to the anterior rectum (8).
The above procedures have recurrence rates of up to 12 %, and almost all patients with the Wells procedure complain of a tendency to constipation. The type of foreign material does not affect the recurrence rates (6, 25, 33); Marlex is superior in terms of infection rates (14, 18). However, the use of foreign material carries its own risks: Fistula formation, stenosis and erosion (12). Studies suggest that continence and constipation issues are more likely to be resolved by sole suture rectopexy than by rectopexy with foreign material (10).
1.1.3 Resection rectopexy (Frykman-Goldberg)
The procedure described by Frykman (11) combines rectopexy and sigmoid resection and has the following objectives:
- Resection of the redundant sigmoid, which either exerts a caudad pressure or may kink against the rectum and thus have an obstructive effect.
- More stable fixation of the stretched rectum
- Scarred fibrous fixation of the rectum at the descendorectostomy
- Improvement of any pre-existing constipation
While the combined procedure has a low risk of recurrence and the improvement in continence is comparable to that of rectopexy without resection, the risk of postoperative constipation is significantly lower and apparently a result of the resection (19, 20).
Surgical aspects of abdominal procedures
The type of access - open or laparoscopic - has no impact on the recurrence rate and functional results (4, 14). Benefits of the minimally invasive procedure include reduced postoperative pain, faster convalescence and shorter hospital stays.
When mobilizing the rectum, incomplete transection of the lateral attachments seems to increase the recurrence rate, but the functional results are more favorable (21, 23, 28).
2. Local techniques (perineal, transanal)
The original benefit of local procedures, avoiding laparotomy, must be reconsidered in view of the minimally invasive techniques available today. While wrapping the anus with subcutaneous foreign material or muscle has become obsolete due to considerable complication and recurrence rates, the following local measures may be considered in patients contraindicated for invasive procedures (26):
2.1 Rehn-Delorme procedure
In the procedure described by Rehn (9) and modified by Delorme, the mucosa is separated transanally from the sphincter and the muscularis propria and the latter is plicated in the area of the prolapsed rectum, thereby shortening the muscle tube. After resection of the now redundant mucosa, it is readapted. The procedure may be performed in analgesic sedation but is not suitable in pronounced prolapse. While studies showed an improvement in continence, they have also demonstrated a rather high recurrence rate.
2.2 Perineal rectosigmoidectomy (Altemeier)
In the Altemeier procedure (1, 5), the transanal resection of the rectum and parts of the sigmoid is followed by subsequent restoration of continuity at the level of the dentate line, comparable to a colon pouch (35). This procedure may be combined with a levatoroplasty (32). While the recurrence rate is lower compared to the Rehn-Delorme procedure, the functional results regarding incontinence and fecal spotting are less favorable.
Choosing the technique
Due to the inconsistent data situation in the treatment of rectal prolapse, no evidence-based recommendations can be given at present regarding the choice of procedure (2, 7, 15, 16). There is no clearly superior procedure in the treatment of rectal prolapse; each surgical technique has its own benefits and drawbacks:
- Transabdominal procedures excel with their lower recurrence rates
The efficacy of sole suture rectopexy is comparable to the procedures employing where foreign material
- The use of foreign material carries its own risks
- Resection rectopexy seems to be beneficial in pre-existing constipation, especially when the sigma is elongated.
- The laparoscopic approach has no downsides; its benefits include less postoperative pain and faster convalescence.
- Local techniques but less operative burden on the patients but have poorer functional results.
The choice of procedure should therefore be governed by the patient's resilience, the size of the prolapse and medical history of functional disorders.
Abdominal access not possible (multimorbid high-risk patient)
> Small prolapse: Rehn-Delorme
> Big prolapse: Altemeier
> In case of incontinence: additional levatoroplasty
Abdominal access is possible: Rectopexy, preferably laparoscopic
> Suture rectopexy
> Mesh rectopexy
> Pre-existing incontinence: no resection
> Pre-existing constipation with redundant sigmoid: Resection