Prolapse of the rectum can be differentiated into
- Partial prolapse and
- Complete prolapse.
Partial prolapse: When only the mucosa and sub-mucosa of the rectum come out through the anus, it is called partial prolapse. The length of such prolapse is never more than 3.5 cm.
Etiology and occurrence: This condition occurs more often in extremes of life like children below 3 years and elderly people.
- Due to non-developed sacral curve and
- Diminished tone of the anal musculature.
- Loss of anal sphincter may cause partial prolapse.
- Third degree prolapse.
- Loss of weight and diminution of para-rectal fat.
- Some loss of tone of anal sphincter.
- Third degree haemorrhoid.
- In females, torn perineum.
- Excessive staining due to urethral obstruction from enlarged prostate or excessive coughing from bronchitis.
Treatment for Rectal Prolapse
- Digital reposition of the partial prolapse may help a lot. The index finger is lubricated and protrusion is pushed up through the anal canal and the finger is gradually withdrawn. Attention to bowel habit, avoiding straining at stools, control of diarrhoea and dietetic adjustments in case of malnutrition are supportive treatments to be followed.
- Sub-mucous injection with 5% phenol in almond oil is given.
- Thiersch’s operation: When conservative measures fail this operative is done where a suture material (chromic catgut wire) is used as a mechanical support by the fibrous deposits around the anal canal. The wire can be removed after 3 months if required.
- Excision of prolapsed mucosa is also an operative of choice in case with third degree piles.
- Complete prolapse: In this condition, the rectum comes out through the anus and the protrusion is more than 3.75 cm in length and usually about 10 cm in length.
- Complete prolapse is rare in children. It may occur at any age but is more common in elderly. Women are affected five times more than the men.
- Bowel habit: Long history of difficulty with defecation. In about 2/3rd of cases, this type of history can be elicited.
- Laxity of anal sphincter is the most obvious abnormality.
- Sliding hernia: Complete prolapse is often considered to be a type of sliding hernia.
- Lack of rectal fixation: If muscles of pelvic floor are weak, it can cause complete prolapse.
- Rectal intussusceptions: Rectum folds on itself and passes through the pelvic diaphragm and ultimately comes out of the anus. Cause is unknown.
There are various operations designed by various surgeons. Common operations are given below.
- Ivalon sponge wrap operation (Wells): Wells described this operation in 1959. A rectangular sheet of Ivalon sponge is sutured to the sacrum and the rectum is drawn up to make it taut. Ivalon sponge will initiate fibrosis and fix the rectum in place.
- Rectopexy (Lockhart-Mummery) operation: The incision and preliminary steps are similar to the previous operation. A curved incision is made midway between the anus and coccyx bone.
- Rectal sling operation.
- Resection operations
- Anterior resection of the rectum: In this technique, rectum (anterior peritoneal reflexion) is removed and resection is done at recto-sigmoid junction.
Other operative are perineal recto-sigmoidectomy and operations on the pelvic floor and perineum.
Despite a successful operation to treat rectal prolapse and careful management with the regulation of bowel habits, a small proportion of patients will have persistence of symptoms. These are mainly varying degrees of incontinence due to anal sphincter dysfunction. The simplest method for trying to improve sphincter function is by exercising the pelvic floor muscle and by applying faradic stimulation.