Rectal Fixation, Abnormal

• • Group of diseases in which the attachment of the rectum to the sacrum has lengthened, allowing the rectum to block the act of defecation, to protrude into the vagina, or to prolapse through the anus

  • Increased mobility related to chronic straining

  • May be secondary to colonic dysmotility

  • Includes internal intussusception, rectal prolapse

Epidemiology

• • Cause of rectal prolapse poorly understood; considered a form of intussusception

  • High incidence of rectal prolapse noted in patients affected by mental retardation

  • Female:male ratio is 5:1

  • 50% of patients with rectal prolapse are male or nulliparous women

Symptoms and Signs

• • Internal intussusception: Sense of rectal fullness, urge to defecate, mass

  • -Mass may be ulcerated, located anterior, 4-12 cm from the anal verge

  • Rectal prolapse: Rectal bleeding, mucus discharge, tenesmus, incontinence, pain, feeling of incomplete evacuation

  • -Large external mass of prolapse tissue with concentric mucosal rings

  • Rectal exam may reveal decreased or absent sphincter tone

Laboratory Findings

• • Histologic exam reveals diffuse submucosal cysts with a characteristic fibrosis pattern distinguishing it from colorectal malignancy

  • Anal manometry may reveal diminished luminal pressure

Imaging Findings

• • Sigmoidoscopy may reveal the circumferential intussusceptum or an ulcerated mass that appears malignant

  • Defecography may demonstrate rectal prolapse or intussusception

  • Evaluation of the entire colon with colonoscopy is necessary to rule out a malignancy

• • Anorectal malignancy

  • Hemorrhoids (prolapsed)

Rule Out

• • Colorectal malignancy

• • Patients with internal intussusception and rectal prolapse need anorectal manometry, pudendal nerve latency studies, defecography, and barium enema or colonoscopy

  • Defecography will show the intussusception or prolapse and may reveal the cause

  • Evaluation of the entire colon with either barium enema or colonoscopy is necessary to rule out a malignancy

  • For patients without active prolapse, it may be necessary to give an enema, allow the patient to defecate, and then examine the perineum

  • -This often induces a prolapse, allowing the diagnosis to be made in the office

• • Mild to moderate intussusception is treated with bulk agents, modification of bowel habits, and reassurance

  • The patient is instructed to stimulate a bowel movement in the morning and avoid the urge to defecate the remainder of the day because the fullness they sense is the proximal rectum intussuscepting into the distal rectum

  • -With time, the urge to defecate resolves and so does the intussusception

Surgery

• • Two classes of operations for rectal prolapse: abdominal and perineal

  • -Abdominal procedures have a lower recurrence rate and preserve the reservoir capacity of the rectum but carry more risk

    -Perineal procedures avoid an intra-abdominal anastomosis but remove the rectum, eliminate the rectal reservoir, and have higher recurrence rates

    -The abdominal procedures are generally preferred in ...