Benign Anorectal Pathology

In this article, we cover common benign anorectal pathologies including haemorrhoids, fissures & fistulas with a quick overview of their assessment & management.

Our Webinar

YouTube player

Basic anatomy

  • Anatomical position of anus is described by a clock in the lithotomy position (lying on back with legs apart, pubic symphysis is 12 o’clock, coccyx is 6 o’clock)
  • Internal anal sphincter – surrounds upper 2/3rds of anal canal. Involuntary. Smooth muscle.
  • External anal sphincter – surronds lower 2/3rds of anal canal. Voluntary. Skeletal muscle
  • Pectinate line

Haemorrhoids (Piles)

  • What is it?
    • Swollen vein in lower rectum
  • How does it present?
    • Painless PR bleeding in bowl/on wiping. Itching.
    • Pain if thrombosed
  • Risk factors
    • Heavy lifting, prolonged sitting, obesity, constipation, pregnancy
  • Diagnosis
    • PR examination (typically impalpable but occasionally visible), proctoscopy
  • Treatment
    • Conservative: sitz bath, dietary fibre, hydration
    • Medical: Anusol, stool softners, (topical GTN if thrombosed)
    • Surgical: Haemorroidectomy (thrombectomy). Band ligation/sclerotherapy 

Fissure in Ano (Anal Fissures)

  • What is it?
    • A mucocutaneous defect of the anal canal (a tear)
  • How does it present?
    • Painful PR bleeding (why is it painful?)
  • Risk factors
    • Mostly idiopathic (90%)
    • Constipation, Crohn’s, tuberculosis
  • Diagnosis?
    • PR examination (90% posterior midline), EUA
  • Management?
    • Conservative – stool softners, fibre, hydration
    • Medical – topical GTN (0.2%) or diltiazem (2%). Botulinum toxin injection.
    • Surgical  – lateral sphincterotomy (10% incontinence to flatus) , advancement flaps

Fistula in Ano (Anal Fistulas)

  • What is it?
    • Abnormal connection between two epithelial surfaces (rectum+skin with 2x openings)
  • How does it present?
  • Risk factors
    • Crohn’s, tuberculosis, diabetes, HIV
  • Diagnosis?
    • PR examination 
    • EUA, MRI
  • Goodsall’s rule
    • Within 3cm of the anus, anterior openings will follow a straight line into the anal canal, which posterior openings will curve towards the midline and then enter the
    • Of clinical importance when trying to find the internal openings during surgery (via PR and using a Lockhart-mummery probe)
  •  Management
    • Abscess -> I&D (secondary intention) +/- sepsis 6
    • Fistula usually once infection resolves (if it was present):
      • Fibrin glue (50% failure)
      • Seton 
      • Fistulotomy “lay open” (CI: Crohn’s, high tract)
      • Complex surgery (advancement flaps)

Written by Dr Marc Huttman (FY2)

How useful was this post?

Click on a star to rate it!

Average rating 4.1 / 5. Vote count: 14

No votes so far! Be the first to rate this post.

As you found this post useful...

Follow us on social media!

We are sorry that this post was not useful for you!

Let us improve this post!

Tell us how we can improve this post?

Related Posts

Maxillofacial Surgery
Orofacial Infections
Orofacial infections are a common A&E presentation and are...
Diverticular Disease
Diverticular Disease
Diverticulae can occur throughout the gastrointestinal tract...
Appendicitis
Appendicitis
Appendicitis is a one of the most common abdominal emergencies...

Leave a Comment

Your email address will not be published. Required fields are marked *

Follow us

Favourites

Newsletter

Trending Now

Understanding the MSRA
The Multiple Specialty Recruitment Assessment (MSRA) is a computer-based exam increasingly being used...
Passing the Prescribing Safety Assessment (PSA)
The PSA is aimed at final year medical students and those graduating overseas to assess their competency...
Resident Doctor's Pay Calculator 2024
We’ve created a pay calculator to help you better understand your salary, how much tax you’ll...
Paracetamol Overdose
Paracetamol overdose is a common presentation in A&E and so you may often find yourself looking after...
Common Viral Infections (exanthem) in Paediatrics
Viral infections are extremely common in paediatrics and a common presentation to paediatric A&E is...
Prescribing IV Fluids
There are certain situations where you need to prescribe IV fluids which vary from fluid resuscitation...
PICC Lines and Midlines
You may well be asked to take blood from a PICC line or be called to see a patient because their PICC...

Sign up for our awesome resources & exclusive discount codes!

Join 80,000+ users who have signed up for our free weekly webinars, referral cheat sheet, pay calculator & exclusive discount codes for Pastest, Quesmed, Medibuddy and many others!