rectal prolapse

Question 1

definition of rectal prolapse

Answer 1

abnormal protrusion of the full thickness (or only the mucosal layer) of the rectum through the anus

partial/type 1 = mucosa only

complete/type 2 = all layers - more common

Question 2

aetiology of rectal prolapse

Answer 2

prolongued straining in association with abnormal rectal anatomy or physiology eg:

• deep pouch of douglas,
• pelvic floor weakness,
• poor fixation of rectum to sacrum,
• reduced anal sphincter pressure

chronic neurological and psychological disorders

Question 3

RF of rectal prolapse

Answer 3

raised intra-abdo pressure

• constipation
• causes of increased straining eg BPH
• chronic cough
• pregnancy

weakness of pelvic floor

• elderly
• multiple pregnancies
• damage to pudendal nerve or sacral roots (obstetric injury, dm neuropathy, pelvic tumours)
• previous perineal surgery - management of anal fistulas
• connective tissue disorders - Ehler Danlos
• previous trauma to the anus or pelvic area - multiple pregnancies
• neurological conditions eg cauda equine syndrome, MS

CF - children

Question 4

epidemiology of rectal prolapse

Answer 4

relatively common

5-10/1000

2 peaks

• <3yrs (male = female)
• elderly 60-70yrs (female more)

Question 5

sx of rectal prolapse

Answer 5

protruding anal mass - initially related to defecation

may require digital replacement

constipation

faecal incontinence

passing mucus or bleeding PR

pruritis ani

may present as emergency - irriducible or strangulated prolapse

Question 6

signs of rectal prolapse

Answer 6

prolapse may be seen on straining

severity varying from protruding rectal mucosa to frank rectal prolapse (if >5cm, invariably a complete prolapse)

may be ulcerated or show necrosis if vascular supply is compromised

DRE - reduced anal sphincter tone, mass, pelvic floor pathology

in partial - radial folds present in the mucosa, only double layerd mucus membrane palpated

in complete - concentric mucosal folds, all 4 layers palpated. sulcus or groove may be present between emerging mass and walls of anal canal

Question 7

pathology of incomplete prolapse

Answer 7

when prolapse only involves the mucosa

<4cm in length

seen in children and adults

associated with excessive straining, constipation and haemorrhoids

Question 8

pathology of complete prolapse

Answer 8

involves the entire rectal wall and intervening peritoneal sac

>4cm in length

occuring mainly in adults

associated with weak pelvic and anal musculature

associated with floppy and redundant sigmoid colon

disease starts with prolapse only on defecation with spontaneous retreaction - can progress to full prolapse

Question 9

Ix for rectal prolapse

Answer 9

imaging:

• proctosigmoidoscopy
• defecating protogram
• barium enema

anal sphincter manometry

pudendal nerve studies

sweat chloride test - in children as approx 10% have CF

Question 10

mx of rectal prolapse

Answer 10

rectopexy - fix the rectum to the sacrum (abdominal approach)
* +- mesh insertion
* +- rectosigmoidectomy

Delorme’s procedure (perineal approach) - anal encirclement with a thiersch wire