Anal Fissure

Question 1

def

Answer 1

an elongated ulcer on the long axis of the lower anal canal

Question 2

aetiology

Answer 2

traumatic
-posterior anal lining - constipation (straining, passing hard stools)
-anterior anal lining - childbirth
inflammatory
-crohns disease
-ulcerative colitis

Question 3

epi

Answer 3

common
<40yrs
incidence 1:350, male:female

Question 4

history

Answer 4

severe burning pain on defaecation

bleeding per rectum (bright red, small in voiume, on paper)

Question 5

examination

Answer 5

inspection reveals a sentinel pile (external lump associated with a tear)
chronic fissures may present with a firm ridge

Question 6

pathogenesis

Answer 6

a mechanical tear occurs in the anal mucosa & the underlying sphincter muscle goes into spasm
the spasm worsens the problem by pulling the edges of the tear apart
poor wound healing due to reduced blood flow in the posterior midline of the anoderm

Question 7

investigations

Answer 7

diagnosis made on history & examination

Question 8

management

Answer 8

conservative
-soft, easily passable stools
medical
-topical GTN/diltiazem which reduce spasm or sphincter & increase blood flow to encourage wound healing
surgery
-lateral internal sphincterotomy (internal sphincter is partially divided to reduce spasm, this allows wound healing)
-botulinum toxin to paralyse part of the internal sphincter

Question 9

complications

Answer 9

chronic fissure & chronic pain
complications of surgery
-faecal incontinence
-bleeding recurrence

Question 10

prognosis

Answer 10

common recurrence
50% treated with topical nitrates
10% treated with lateral sphincterotomy