Anal Fissure

Question 1

Definition

Answer 1

· A painful tear in the squamous lining of the lower anal canal

· NOTE: 90% of anal fissures are posterior (anterior anal fissures tend to occur after childbirth)

Question 2

Aetiology/Risk factors

Answer 2

· Most are caused by hard faeces

· Anal sphincter spasm can constrict the inferior rectal artery, causing ischaemia and impairing the healing process

· Rare causes: syphilis, herpes, trauma, Crohn’s, anal cancer, psoriasis

Question 3

Epidemiology

Answer 3

· Affects 1/10 people during their life time

· Both sexes are affected equally

· Can occur at any age

· Most cases occur in children and young adults: 10-30 yrs

Question 4

Presenting symptoms

Answer 4

· Tearing pain when passing stools

· There may be a little bit of blood in the faeces or on the paper

· Anal itching (pruritus ani)

Question 5

Signs on physical examination

Answer 5

Tears in the squamous lining of the anus on examination

Question 6

Investigations

Answer 6

Examine the anus

Question 7

Management plan (conservative)

Answer 7

o High-fibre diet

o Softening the stools (laxatives)

o Good hydration

Question 8

Management plan (medical)

Answer 8

o Lidocaine ointment (local anaesthetic)

o GTN ointment (relaxes the anal sphincter and promoted healing)

o Diltiazem (relaxes the anal sphincter and promotes healing)

o Botulinum toxin injection

Question 9

Management plan (surgical)

Answer 9

o Lateral sphincterotomy

o This relaxes the anal sphincter and promotes healing but it has complications (e.g. anal incontinence) so it is reserved for patients who are intolerant or not responsive to non-surgical treatments

Question 10

Possible complications

Answer 10

Chronic anal fissure

Question 11

Prognosis

Answer 11

· In most people, the fissure will heal within a week or so

· Treatment revolves around easing pain by keeping the stools soft and relaxing the anal sphincter to promote healing