The exact pathogenesis and etiology of rectal prolapse remain unclear: Is it a sliding hernia, an intussusception, or a combination of both mechanisms? The following anatomical-functional changes are found in varying degrees in this condition:
- an abnormally deep Douglas pouch (3, 17, 24)
- a diastasis of the levator muscles
- a functional weakness of the internal and external anal sphincters (3, 17)
- a weak pelvic floor musculature
- a pudendal neuropathy (17, 24)
- a mobile mesorectum with insufficient dorsal and lateral fixation of the rectum (17, 24, 34)
- an elongated, redundant sigmoid colon (17, 24, 34).
Which of these changes favor a rectal prolapse and which are secondary consequences is ultimately unclear and can hardly be clarified in the context of diagnostics.
Treatment goals are the elimination of the prolapse and the restoration of defecation and continence behavior. The following therapeutic options are available (17, 24, 34):
- Fixation of the rectum to the sacrum
- Resection or plication of the redundant bowel.
Distinctions are made between transabdominal and local procedures.
1. Transabdominal Procedures (Laparotomy, Laparoscopy)
1.1 Rectopexy
The rectum is refixed to the presacral fascia, thereby eliminating the insufficient suspension to the sacrum. Stretching the rectum relieves the pelvic floor, which is intended to promote regeneration of the pelvic floor muscles. The following pexy variants are distinguished:
1.1.1 Suture Rectopexy
In the procedure first performed by Sudeck (29), the rectum is mobilized down to the pelvic floor and attached to the promontory with individual sutures. A presacral fibrosis caused by mobilization is intended to further stabilize the fixation. Recurrence rates of up to 10% are described, and reports on postoperative functional disorders vary significantly (21).
1.1.2 Rectopexy with Foreign Material
Foreign material is intended to lead to a more extensive presacral fixation of the mobilized and stretched rectum. Depending on the position of the material, the following are distinguished: anterior sling rectopexy according to Ripstein (27), lateral fixation according to Orr-Loygue, and posterior mesh rectopexy according to Wells (31). Another variant is ventral rectopexy, where, assuming that mobilization of the rectum leads to postoperative evacuation disorders (23, 28), the rectum is only mobilized in the rectovaginal space and attached to the promontory via a mesh fixed ventrally on the rectum (8).
The mentioned procedures have recurrence rates of up to 12%, and the Wells procedure leads to a tendency towards constipation in almost all patients. The type of foreign material has no influence on the recurrence rates (6, 25, 33), regarding infection rates, Marlex is superior (14, 18). However, the use of foreign material has its own risks: fistula formation, stenosis, and erosions (12). Studies suggest that continence and constipation problems are likely to be resolved more effectively by suture rectopexy alone than by rectopexies 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 goals:
- Removal of the redundant sigmoid, which either exerts a downward pressure or can kink against the rectum, thereby acting obstructively
- more stable fixation of the stretched rectum
- formation of a scar-fibrous fixation of the rectum in the area of the descending rectostomy
- improvement of pre-existing constipation
The combination procedure has a low recurrence risk, the improvement in continence is comparable to that of a pexy without resection, but the risk of postoperative constipation tendency is significantly lower and apparently based on the resection (19, 20).
Technical Aspects of Abdominal Procedures
The access route – open or laparoscopic – has no influence on recurrence rate and functional outcomes (4, 14). Advantages of the MIC procedure include less postoperative pain, faster recovery, and shorter hospital stay.
During mobilization of the rectum, incomplete transection of the lateral suspension seems to increase the recurrence rate, while functional outcomes are more favorable (21, 23, 28).
2. Local Procedures (Perineal, Transanal)
The advantage of local procedures was originally the avoidance of a laparotomy, which has been relativized in view of the MIC techniques available today. While encircling procedures of the anus with subcutaneously introduced foreign material or muscle are now obsolete due to significant complication and recurrence rates, the following local measures are considered for patients with contraindications 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 gathered in the area of the prolapsed rectum, resulting in a shortening of the muscularis tube. After resection of the now excess mucosa, it is readapted. The procedure can be performed under analgosedation but is not suitable for a pronounced prolapse. Studies show an improvement in continence but also a relatively 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 performed with subsequent restoration of continuity at the level of the dentate line, comparable to the creation of a colon pouch (35). Combination with a levatorplasty is possible (32). While the recurrence rate is lower compared to the Rehn-Delorme procedure, the functional outcomes regarding incontinence and soiling are less favorable.
Choice of Procedure
Due to the heterogeneous data situation, no evidence-based recommendations can currently be made regarding the choice of procedure for the treatment of rectal prolapse (2, 7, 15, 16). There is no clearly superior method for treating rectal prolapse; rather, each surgical procedure has its own advantages and disadvantages:
- transabdominal procedures are characterized by a lower recurrence rate
the efficiency of pure suture rectopexy is comparable to pexy procedures using foreign material - the use of foreign material carries its own risks
- resection rectopexies seem advantageous in pre-existing constipation, especially with an elongated sigmoid
- the laparoscopic approach has no disadvantages; advantages include less postoperative pain and faster recovery
- in local techniques, the surgical burden is lower, but the functional outcomes are poorer
Decisive for the choice of procedure are thus the patient's resilience, the size of the prolapse, and anamnesis of functional disorders.
Abdominal Access Not Possible (Multimorbid High-Risk Patient)
> small prolapse: Rehn-Delorme
> large prolapse: Altemeier
> in case of incontinence: additionally levatorplasty
Abdominal Access Possible: Rectopexy, Preferably Laparoscopic
> suture rectopexy
> mesh rectopexy
> in pre-existing incontinence: no resection
> in pre-existing constipation with redundant sigmoid: resection