The precise pathogenesis and etiology of rectal prolapse are still under discussion: Is it a sliding hernia, an intussusception, or a combination of both mechanisms? This clinical entity is characterized by the following functional anatomical pathologies which are present in varying degrees:
- Atypically low Douglas pouch (3, 13, 19)
- Levator ani muscle diastasis
- Functional weakness of the internal and external anal sphincters (3, 13)
- Weak pelvic floor muscles
- Pudendal neuropathy (13, 19)
- Mobile mesorectum with inadequate posterior and lateral fixation of the rectum (13, 19, 29)
- Elongated, redundant sigmoid colon (13,19,29)
Ultimately, it remains unclear which of the changes are conducive to rectal prolapse and which are sequelae, and this is almost impossible to clarify in diagnostic work-up.
Treatment aims to eliminate the prolapse and restore defecation and continence. The following treatment options are available (13, 19, 29):
- Fixation of the rectum to the sacrum
- Resection or plication of the redundant bowel
A distinction is made between transabdominal and local procedures.
1. Transabdominal procedures (laparotomy, laparoscopy)
1.1 Rectopexy
The rectum is fixed to the presacral fascia, thus eliminating its inadequate fixation to the sacrum. Stretching of the rectum relieves the pressure on the pelvic floor and is intended as a means of regenerating the pelvic floor muscles. Rectopexy includes the following types of procedure:
1.1.1 Suture rectopexy
In suture rectopexy first performed by Sudeck (24), the rectum is mobilized down to the pelvic floor and attached to the promontory with interrupted sutures. It is hypothesized that mobilization-induced presacral fibrosis will further strengthen the fixation. Recurrence rates of up to 10% have been reported and the range of postoperative functional disorders described varies widely (16).
1.1.2 Rectopexy with foreign material
Foreign material supposedly contributes to a more extensive presacral fixation of the mobilized and stretched rectum. Ripstein procedure (anterior sling rectopexy (22)), Orr-Loygue procedure (lateral fixation) and Wells procedure (posterior mesh rectopexy (26)) differ in their position of the material. Another variant is anterior rectopexy, where the rectum is mobilized only in the rectouterine pouch and attached to the promontory with a mesh fixed anteriorly to the rectum (6). This technique is based on the concept that mobilization of the rectum results in postoperative defecation difficulties (18, 23).
The above procedures have recurrence rates of up to 12%, and after the Wells procedure almost all patients have a tendency of constipation. The type of foreign material does not affect the recurrence rate (5, 20, 28); Marlex excels in terms of the lowest infection rates (12, 14). However, the use of foreign material has its own risks: Fistulas, stenoses and erosions (10). Studies suggest that problems with continence and constipation are more likely to be resolved with simple suture rectopexy rather than with foreign material (8).
1.1.3 Resection rectopexy (Frykman-Goldberg)
The procedure described by Frykman (9) combines rectopexy and sigmoidectomy, thereby aiming to achieve the following:
- Removal of the redundant sigmoid which exerts caudal pressure or can become angulated against the rectum causing obstruction
- Enhanced fixation of the stretched rectum
- Rectal fixation following fibrous scarring around the descendorectostomy
- Improvement of preexisting constipation
The combined procedure has a low risk of recurrence, improves continence comparable to that of rectopexy without resection, but markedly lowers the potential risk of postoperative constipation apparently due to the resection (15).
Surgical aspects of abdominal procedures
The access route—open or laparoscopic—does not impact the recurrence rate or functional results (4, 12). The benefits of minimally invasive surgery (MIS) include reduced postoperative pain, faster convalescence and shorter hospital stays.
While incomplete division of the lateral stalks during rectal mobilization appears to increase the recurrence rate, the functional results are more favorable (16, 18, 23).
2. Local procedures (perineal, transanal)
The original benefit of local procedures was that they avoided laparotomy; in view of the MIS techniques available today, this aspect has lost its significance. While wrapping the anus with subcutaneous foreign material or muscle has become obsolete due to marked complication and recurrence rates, the following local measures may be considered in patients with contraindications for invasive procedures (21):
2.1 Rehn-Delorme procedure
In the procedure described by Rehn (7) and modified by Delorme, the mucosa is separated transanally from the sphincter and muscularis propria and the denuded muscularis layer is plicated longitudinally around the prolapsed rectum; this shortens the muscularis tube. After resection of the redundant mucosa, it is reapproximated. The procedure may be performed under analgesic sedation but is not suitable in pronounced prolapse. While studies demonstrate improved continence, the recurrence rate is rather high.
2.2 Perineal rectosigmoidectomy (Altemeier)
In the Altemeier procedure (1), transanal resection of the rectum and parts of the sigmoid, with subsequent restoration of bowel continuity, is carried out at the level of the dentate line as when fashioning a colon pouch (30). This can be combined with levatorplasty (27). While the recurrence rate is lower compared to the Rehn-Delorme procedure, the functional results regarding incontinence and fecal smearing are less favorable.
Selection of the procedure
Due to the present inconsistent data, no evidence-based recommendations can be issued for the choice of procedure used to manage rectal prolapse (2). There is no clearly superior technique in the management of rectal prolapse, with each having its own risks and benefits:
- Transabdominal procedures are characterized by a lower recurrence rate
- The effectiveness of sole suture rectopexy is comparable to that of pexy procedures with foreign material
- The use of foreign material has its own risks
- Resection rectopexy appears to have benefits in cases of preexisting constipation, in particular in elongated sigmoid colon
- Laparoscopy has no drawbacks and offers the benefit of less postoperative pain and quicker convalescence
- While local procedures cause less surgical stress, the functional results are poorer
The key criteria for the choice of procedure are patient resilience, size of the prolapse and reported functional disorders.
Abdominal access not possible (multimorbid high risk patient)
> Minor prolapse: Rehn-Delorme
> Major prolapse: Altemeier
> Incontinence: additionally, levatorplasty
Abdominal access possible: Rectopexy, preferably laparoscopic
> Suture rectopexy
> Mesh rectopexy
> Preexisting incontinence: no resection
> Preexisting constipation with redundant sigmoid: Resection