 |
       |
|
|
PROLAPSE OF THE RECTUM
P N Joshi
Ex. Hon. Prof. and Hon. Surgeon, The Dept. Of Proctology-Grant Medical College and GT Hospital, Mumbai; Hon. Colon and Rectal Surgeon, Bhatia General Hospital, Mumbai.
Protrusion of the rectum through the anus is termed as prolapse of the rectum. If only mucosa protrudes it is termed as partial prolapse and if the entire thickness of the rectal wall protrudes it is termed as a complete prolapse.Rectal prolapse in children
Prolapse of the rectum in children is a fairly common paediatric surgical problem in hospital practice in the tropics.
Predisposing factors
1.The common age group is below the age of five years.
2.Sex ratio is two females to three males.
3.It is much more common in the lower strata of society because of under and malnourishment, dirty habits and worm infestation.
Precipitating factors
1.Diarrhoea accompanied by tenesmus and straining at stool.
2.Extreme under-nourishment as a result of diarrhoea or otherwise.
3.Mal-absorption syndrome, e.g. coeliac disease.
Specific causes
1.The commonest cause in the tropics is worm infestation, especially round and thread worms. No treatment will succeed without eradication of this problem when it exists.
2.In ectopia vesica, there is usually an associated prolapse of the rectum due to wide separation of the symphysis pubis and levator sling.
3.In a small number of cases of myelo-meningocoele and sacral agenesis of the anus and defective levator sphincters.
Types
1.Incomplete or mucosal prolapse.
2.Total or all-coat prolapse. This prolapse includes the recto vesical pouch or the pouch of Douglas with small bowel in the anterior prolapsed wall.
Clinical features
Haemorrhage per rectum is hardly ever a feature of either incomplete or complete prolapse. In incomplete prolapse, the mother gives a history of some tissue coming out of the anus on defaecation which automatically reduces by itself or can be easily pushed back after the act. In complete prolapse, variable lengths of the rectum are out of the anal ring, from 1 to 6 inches. The mucous membrane may be abraded or ulcerated and bleeds at places. The child is otherwise comfortable.
Differential diagnosis
1.Rectal polyp may bleed severely or prolapse and can be identified by inspection, palpation and proctoscopy.
2.Prolapse of an intussusception, especially a chronic one. When the examining finger can be passed through the side of the prolapse, it is a case of intussusception; if not, it is a case of simple prolapse of the rectum.
Treatment
There is no place for an operative line of treatment in childhood prolapse in the vast majority of cases. The only exception is persistence of the prolapse after vigorous treatment and control of diarrhoea, worm infestation and malabsorption.
Conservative or Medical Treatment
1.Treat the diarrhoea.
2.Treat the worm infestation. The most difficult problem is the whip worm.
3.Treat the under-nourishment of the child.
4.When the child is brought with a complete prolapse then (a) sedate the child, (b) nurse the child in the trendelenburg position, (c) If the prolapse is not reducible then gently push it back by pressure on the apex by the thumb and fingers of one hand, (d) keep the prolapse reduced by strapping the buttocks together. Do not block the anus by a tight wad of gauze and cotton. It is not physiological and never succeeds.
Sclerosing injection
This is usually reserved for prolapse of redundant mucosa after an anoplasty or recto-plasty for imperforate anus. Five per cent phenol in olive oil, about 1/2 ml each, is injected submucosally in three equidistant quadrants of the rectal circumference, 1/2 inch above the anal valves.
Operative treatment
1. Thiersch operation : This is ideally suited for prolapse occurring in meningomyelocoele and sacral agenesis. Introduce a suture of nylon thread subcutaneously round the anus and tie it, while a small straight anal dilator the size of the index finger is held in the anal canal.
2. Lockhart mummery's rectopexy : Through a small transverse skin incision between the coccyx and the posterior anal margin, the anal canal and the rectum is separated in the midline from the sacrum right upto the promontory. The space, so created, is packed with gauze which is changed every 10 days. Usually it takes about 3 to 4 weeks for the retrorectal space to be obliterated by fibrous tissue. This is the simplest and the safest operation in a complete childhood prolapse.
3. Singh JP (1990) has advocated posterior rectal wall stiffening. He does vertical plication of the distal 8-10 cm of posterior rectal wall through a transverse incision at the sacrococcygeal junction. He has been able to achieve 100% cure in 40 cases.
RECTAL PROLAPSE IN ADULTS
In adults complete variety is more common than partial. Partial prolapse is common in elderly and weak persons. It may also occur after severe attack of diarrhoea or dysentery or in paraplegics who have poor sphincter tone. The treatment of partial prolapse consists of control of diarrhoea. Electrical stimulation of sphincteric muscles, injection of sclerosing agent or Thiersch's operation may be required for those who have poor sphincter tone and are relatively incontinent. The excision of mucosa in three quadrants gives good results.
Complete rectal prolapse in adults
It is a difficult problem as its aetiology is not known and treatment is far from satisfactory. In western countries it is the disease of the old age and women are more commonly affected than men. In addition to occurrence of prolapse they are relatively incontinent to stools and soiling of garments makes their social life uncomfortable which leads them to live a secluded life. In women non-parous and multiparous are affected equally, indicating that parturition trauma does not play significant role in causing this condition. Very few of them have associated uterine prolapse.
The men who are affected by this condition are in the middle age group. In India and other Asian countries rectal prolapse is more commonly seen in men than women. The majority of them, both men and women, are fairly continent and are in middle age group. In the authors series 80% of them were between 20 years and 50 years. Experience of other Indian authors is similar.
Author F M Age at on-set
F MGolighar (1961) . 61 11 60yrs. 20-40 yrs. Friedman (1962) 38 5 60 yrs. Muir (1962) 45 . 3 60 yrs Porter (1962) 389 147 60 yrs. Hughes and Glead - II (1962) 148 20 40-70 yrs. 20-40 yrs. Joshi Aptekar et al (1967) 1 29 45 yrs. 14-20 yrs. Joshi Menda Chulani (1978) 5 31 40 yrs. 15-20 yrs.
M F Jagesia KH (1974) 20 1 Barat AK (1974) 25 - Prasad PB (1974) 27 3 Sing ML (1974) 24 3 Rangabashyam (1974) 14 2 Cherian TK (1979) 38 1 Joshi PN (1976 to 1997) 361 23 Chivate SD (1976-1986) 91 11
Clinical features
All of them complain of rectal protrusion at stool which has gradually increased in length in due course of time. The history may be of six months to 10 years or more. Majority of them suffer from recurrent attack of dysentery and worm infestations which produces rectal irritation. They also complain of constipation requiring more than two or three visits to the toilet for a complete evacuation. They are habituated to strain at stools and spend more time in the toilet at each visit. Few of them complain of mucous or serosanguinous discharge and soiling of garments. Majority of them are continent to solid stools but some may suffer from incontinence during the attack of diarrhoea or dysentery. Occasionally they present with irreducible rectal prolapse or rectal perforation with evisceration of small bowel. Size of the prolapse varies from three inches to ten inches or more and rectal mucosa shows chronic inflammatory changes. Sphincter tone may be fair to poor but never normal. Anus and pelvic apertures are widened as evidenced during rectal examination. The contraction power of sphincter muscle and levator is also reduced.
Pathophysiology
There is blunting of rectal sensations and larger than normal rectal pressure is required to provoke the defaecatory reflex. This is demonstrated by inserting a balloon attached to a sphygmomanometer. Normally 200 to 250 ml of volume or a pressure of 20 to 40 mm of mercury is sufficient enough to produce a defaecatory reflex. In case of rectal prolapse, the volume required is higher and pressure to provoke the reflex is increased to 60 to 80 mm of mercury. As the call to stool is less definite, straining may not always be carried out at the most appropriate time. The prolong neglect of answering the call sets up a vicious circle, larger and larger volumes being required to provoke a defaecatory reflex. This leads to dyschezic constipation and inadequate frequent bowel actions for complete evacuation of the faeces (Pellet type of constipation).
The mental status of these patients is not normal. They derive some sort of perverted pleasure in forcing their rectum out. This is evidenced by the fact that they seek medical advice after a long duration of its existence or when complications occur.
Aetiology
As the exact aetiology is not known different authors working on this problem have put forwardvarious causative factors based on their observations.
1.Theory of sliding hernia.2.Undue mobility of the rectum as a cause of prolapse
3.Laxity of levator and sphincteric muscles.
4.Theory of intussusception.
Theory of sliding hernia
Moschcowitz (1912) believed that the rectal prolapse is a form of sliding hernia, the pouch of Douglas being the hernial sac, which presses the anterior rectal wall into the rectal lumen, and then through the anal canal to the exterior. According to him this occurs in four stages.
Stage 1 : Incipient prolapse - In this stage the peritoneum is pushed into the weak spot of fascia transversalis which exists in front of the rectal wall.
Stage 2 : Partial prolapse - In this stage there is invagination of anterior rectal wall.
Stage 3 : Incomplete prolapse - In this stage there is invagination of anterior and lateral wall, followed by posterior rectal wall but it has not yet emerged through the anus.
Stage 4 : Complete rectal prolapse - In this stage the rectum protrudes through the anus gradually increases in its length. In support of his theory he states that, the finger inserted in the rectum when pressed against the anterior wall prevents the occurrence of prolapse but when pressed laterally or posteriorly does not do so.
In the initial stages a distinct weakness and an impulse on cough can be demonstrated by pressing against the anterior rectal wall when patient is made to strain or cough. He has followed up these cases who later on developed full fledged complete rectal prolapse. Author has observed that during sigmoidoscopy in knee chest position, if these patients are asked to strain down one can visualize the protrusion of anterior rectal wall followed by invagination of lateral and posterior walls. As the scope is being withdrawn, the protrusion follows it upto the exterior.
According to Moschcowitz (1912) the deep pouch of Douglas is of acquired origin while others believe that it is due to congenital developmental defect. This they feel is due to non-obliteration of the peritoneal sac which extends deep down upto the pelvic floor, during intrauterine life, which later on gets obliterated to form the fascia of Denonvillers. This is further substantiated by the fact that the peritoneum could be separated with ease from the prostate in these cases of rectal prolapse.
Undue mobility of the rectum as the cause of rectal prolapse
Pemberton and Stalker, (1939); Muir (1955); Ripstein (1965); believe that undue mobility of the rectum leads to occurrence of rectal prolapse. They explain it on the basis of protrusion of the bowel through colostomy stoma. In these patients there is a mobile segment of the colon proximal to the stoma. If the colostomy is performed nearer to descending colon which is relatively fixed and non mobile, no protrusion occurs.
Laxity of levator and sphincteric muscles
Todd (1959) believes that occurrence of rectal prolapse is due to laxity of levator and sphincteric muscles. In support of his belief he sites the example of occurrence of rectal prolapse in a Cauda equina lesion, in which there is weakness and laxity of levator and sphincteric muscles.
The laxity of levator muscles may be due to defective development as in pronogrades they exist as separate muscles and there is a complete mesial slit in the pelvic diaphragm.
Theory of intussusception
Snellman (1962) Broden and Sellman (1968), Deodhar (1996), they all believe that rectal prolapse is a rectal intussusception and not a slidinghernia as originally described by Moschovitz. They have tried to prove their point by taking defaecating cineradiographic pictures. They have observed that intussusception begins at a crucial point which is about 6 to 8 cms from the anal verge. The rectum below the crucial point is thickened while the part above this is thin and more or less normal. The peritoneal ring around the crucial point is also thickened. The crucial point is probably at the level of peritoneal attachment to the rectum on its anterior wall. Author feels that the theory of intussusception does not give satisfactory explanation. The location of the crucial point is very vague. The apex of the intussusception which initially begins at the crucial point keeps changing as the prolapse advances, as evidenced by varying lengths of the prolapse in the same individual.
Mahmaud Helmy (1976), El-Sebai (1961) have stated that Bilharziasis of the rectum and colon may be the cause of the rectal prolapse. They have stated that chronic straining due to dysentery and passage of blood and mucus in stools weakens the pelvic floor. The constant dragging effect of bilharzial polyps also adds to the descent of prolapse. In Indian patients recurrent attacks of dysentery and worm infestations is very common, which produces rectal irritation and habit of straining at stools. Chronic inflammatory changes in the rectal mucosa produces blunting of rectal sensations and hence larger rectal pressure is required to provoke defaecatory reflex. Thus it can be deduced that these factors may be responsible in initiating the onset of the rectal prolapse.
Treatment
There are as many as a hundred or more operative procedures for the treatment of complete rectal prolapse. An ideal and satisfactory procedure is yet to be found. We shall consider only those procedures which are of some value and are practised widely all over the world with fairly good results.
The main theme of these procedures includes one or combination of the following procedures.
1.Narrowing of anal aperture.2.Excision of deep pouch of peritoneum.
3.Fixation of the rectum to sacral hollow and/or pelvic wall.
4.Repair of puborectalis sling and levator floor.
5.Excision or resection of redundant segment either from below or per abdomen.
6.Rectal plication or reversal of intussusception.
7.Electrical stimulation by electrical implants
Thiersch's procedure (1891)
It aims at narrowing of the anal aperture and provoking reaction in the tissues leading to formation of ring of fibrosis. Materials used are silver wire, stainless steel wire or ring, silk, fascia, nylon, Teflon and prolene. The suture is inserted either by a specially devised aneurysm needle or ordinary half circle big sized round body needle. Patient is put on lithotomy position. Small vertical incisions are made in the midline in front and behind the anus, an inch away from anal verge. The incisions are deepened down by blunt dissection by a straight artery forceps. The aneurysm needle is then introduced through the posterior wound and should pass outside the sphincter muscles and not submucosally and then brought out through anterior wound. Nylon or Prolene No. 2 is then threaded in the eye, and the needle is withdrawn. The same procedure is repeated on the other side. Sutures are then tied over an average size examination proctoscope or judging the narrowing by an examination finger. Aperture should be adequate as excessive narrowing might produce faecal impaction while inadequate narrowing may allow the prolapse to protrude which will then be difficult to reduce.
Low anterior resection by Muir (1955)
He does low anterior resection with removal of slack rectum and sigmoid colon making the bowel taut. He excises the pouch of Douglas. In his seriesof 50 cases there had been no recurrence.
Ripstein's operation
The rectum is fully mobilized from all sides and held tautly upwards. A 'T' shaped teflon mesh, two inches wide, is passed round it and the ends are sutured to the sacral fascia about two inches below the promontory. In addition few stitches are passed between the edges of the sling and the anterior and lateral walls of the rectum. He has reported good results.
Abdominal rectopexy (Joshi PN)
After opening the abdomen the rectum is mobilized from all sides, except that the lateral ligaments are not divided. The division of lateral ligaments endangers the injury to the inferior hypogastric plexus leading to impotency. The posterior separation is done upto the coccyx and in front upto the base of the prostate in male and upto the cervix in female. The posterior wall of the rectum is anchored to sacral promontory by non-absorbable sutures. The peripheral portion of the peritoneum is sutured to the rectum in such a fashion that the deep pouch is obliterated. The cure rate is 97%.
Perineal procedures
In these procedures the rectum is mobilized from the sacral hollow and then fixed to the sacrum by prolene mesh or non-absorbable sutures. In addition to this, publication of the levators is also done. Atri 1980, has advocated Graciloplasty.
Electrical stimulation
This procedure of electrical stimulation of muscles of pelvic floor and anus is used for rectal prolapse with incontinence. The stimulation is applied by means of electrodes placed in the region of the anus with an implant receiving aerial and having the power supplied radio frequency link from a source placed above the skin overlying the aerial (Caldnell 1967). The other method in use is to have an external power source connected directly by wires to a plug bearing the electrodes which is placed in the anal canal. This continuous electrical stimulation causes contraction of muscle to maintain increased tone which would preserve continence and hold the prolapse in place. Another way of giving electrical stimulation is to use intermittent stimulation for ten seconds with an interval of twenty seconds. The current voltage is slowly raised over the first four second and then maintained for remaining six seconds. This has helped in removing pricking sensation in the anus.
CONCLUSION
In India, rectal prolapse is more common amongst healthy young males, who are by and large continent to stools. Their distinctive features is the use of squatting position for defaecation which obliterates the ano-rectal angulation. Recurrent attacks of dysentery and worm infestations produce rectal irritation. Presence of a large sigmoid loop aggravates the constipation. The rectal irritation and constipation leads to developing the habit of straining at stools. Presence of a deep pouch of Douglas and laxity of levators are due to congenital development defects. In presence of these pre-disposing factors chronic stress of straining at stools in squatting posture initiates the onset of prolapse in the form of sliding hernia. The rectal fixation and obliteration of the deep pouch of Douglas suffices to offer the cure for this condition. If the sigmoid loop is unduly large, its excision is necessary. Thiersch's operation is indicated in those who have patulous anus and are incontinent to stools.
REFERENCES
1.Chivate SD. "New perineal repair of complete prolapse of the rectum - Updated", Indian Jr of Colo-Proctology 1988; 3 : 62-6.
2.Golighey JC. "Surgery of anus, rectum and colon", 5th edition, Bailliere, Tindall, Cassel, London. 1984.
3.Jerome J Decosse, Ian P Todd. "Anorectal surgery", 1st edition, Churchill Livingstone. 1988.
 |