Inguinal Hernia

Hernia is a protrusion of a viscus or part of viscus through an abnormal opening in the wall of its containing cavity.

Causes Of Hernia
  1. Congenital
    • Developmental disorders 
      • Persistence of the processus vaginalis
      • Failure of complete obliteration of umbilical opening
    • Genetic weakness of collagen
  2. Weakness due to structures entering and leaving the abdomen 
  3. Sharp and blunt trauma 
  4. Weakness due to ageing
  5. Pregnancy 
  6. Excessive intra-abdominal pressure
    • Chronic cough
    • Straining
    • Urinary obstruction
    • Heavy lifting 
Composition Of Hernia
  1. Sac
    • Consist of a mouth, neck, body & fundus 
    • Derived from the peritoneum 
  2. Covering 
    • Derived from the layers of the abdominal wall 
  3. Contents
Classification Of Hernia
  1. Reducible 
    • Contents can completely be returned to the peritoneal cavity
  2. Irreducible
    • Contents cannot be returned 
    • Due to adhesion with the inner sac wall or adhesion of contents itself
  3. Incarcerated 
    • Has no clear cut definition 
    • It is implied to a hernia which is irreducible and developing towards strangulation
  4. Obstructed
    • Bowel in the hernia has good blood supply, but obstructed
  5. Strangulated
    • Blood supply of the bowel has been cut off
    • Gangrene is inevitable, unless relieved 
    • Occurs due to constriction of the contents at the neck 
  6. Infarcted
    • When the contents of the hernia has become gangrenous 

Common varieties of hernia, in order of frequency are….

  1. Inguinal hernia
  2. Femoral hernia
  3. Umbilical & paraumbilical hernia
  4. Incisional hernia
Inguinal Hernia 
Commonest type of abdominal hernia 
Male : Female ratio is 8 : 1
Types of inguinal hernia
  1. Direct inguinal hernia
    • Passes through the posterior wall of the inguinal canal
    • Passes through a weakness in the transversalis fascia in the Hesselbach’s triangle area 
  2. Indirect inguinal hernia
    • Passes through the internal inguinal ring
Indirect Inguinal Hernia
Direct Inguinal Hernia
1. Age
Common in young
Acquired, common in adults and elderly
2. Causes
Congenital (Persistant processus vaginalis)
Acquired, due to weakness in the abdominal wall
3. Origin
Passes through the internal ring
Passes through the posterior wall of the inguinal canal
4. Relation with inferior epigastric vessels
5. Neck
6. Ring occlusion test
7. Reducibility upon lying
No readily
Reduces spontaneously
8. Risk of strangulation
9. Descending to scrotum
10. Recurrence after surgery
Clinical features
  1. Usually self diagnosed as a lump in the groin
  2. Painless
  3. Aching or dragging sensation, specially towards the end of the day
  4. Pain maybe felt with bulging during specific actions like lifting
     Investigations are not usually required
  1. Ultrasonography
  2. MRI
  3. CT scan 
  4. Herniography
    Intraperitoneal contrast injection and subsequent X-Ray 
a. Congenital inguinal hernia 
        At first the patent processus vaginalis is ligated
        Then herniotomy is done at the age of 1 year
b. Adult inguinal hernia 
        Repair is advised for patients with symptoms, irreducibility & bowel obstruction 
        In elderly with asymptomatic, reducible, small sized hernia –  watchful waiting 
        Groin truss is offered to patients who cannot undergo surgery 
        Treatment of the underlying cause of increased intra-abdominal pressure
Postoperative advice – Avoid heavy lifting for 1 – 2 weeks 
Repair can be done as an open surgery or laparoscopically 
Laparascopic approach is recommended for recurrent and bilateral hernias
Can be performed under general or local anaesthesia 
In mesh repair….
        Mesh is placed in front of transversalis fascia in open repairs and fixed by sutures 
        Mesh is placed behind transversalis fasica in laparoscopic repairs and fixed by tacking devices 
Recurrent hernia occurs due to infection, haematoma or poor technique, failure to treat the underlying cause of increased intra-abdominal pressure (chronic cought, straining, heavy lifting, ascites, urinary obstruction)
* Treatment of the underlying cause is essential in preventing recurrence 
Strangulated Hernia 

When the blood supply to the contents of the sac has been cut off, it is said to be a strangulated hernia.

Gangrene may occur after 5 – 6 hours after onset of the first symptoms  

Pathological consequences

Constriction of the contents at the neck

Oedema and increase venous pressure
Impeding arterial blood flow
Bowel necrosis and perforation 
Can lead to complications like peritonitis & septic shock 
Clinical features

  1. Sudden onset of pain at the site of hernia followed by generalised colicky abdominal pain mainly around the umbilicus
  2. Increasing size of hernia
  3. Features of intestinal obstruction (Vomiting, distension, constipation)
  4. On examination 
    1. Tense, tender irreducible hernia 
    2. No cough impulse
    3. Overlying skin is inflamed and oedematous
Spontaneous cessation of pain is a sign of perforation 


* Require urgent surgery 

  1. Preoperative treatment
    • Maintain ABC (Fluid resuscitation is essential)
    • Nasogastric suction
    • Antibiotics 
    • Catheterization of the patient
  2. Surgery
Surgeries Done For Inguinal Hernia
  1. Herniotomy – Excision of the sac
  2. Herniorrhaphy – Repair of fasica transversalis & internal ring
  3. Hernioplasty – Reinforcement of posterior inguinal wall 
Pantaloon Hernia / Saddle Bag Hernia

It is the coexistence of direct and indirect hernias decending on either side of the epigastric artery which appears like the legs of a pair of pantaloons.

Differential Diagnosis Of Inguinoscrotal Swellings

  1. In males
    • Vaginal hydrocele
    • Encysted hydrocele of cord
    • Spermatocele
    • Femoral hernia
    • Incompletely descended testis in the inguinal canal
    • Lipoma of the cord
  2. In females
    • Hydrocele of the canal of Nuck
    • Femoral hernia


Surgical Anatomy Of Inguinal Canal 

It is an oblique passage in the lower abdominal wall which extends from the internal inguinal ring to external inguinal ring 

Length & direction – About 4cm & passes downwards, forwards & medially


Boundaries of inguinal canal 

  • Roof 
    • Lowest fibres of the internal oblique muscle
    • Transversus abdominis muscle
  • Floor 
    • Inguinal ligament
  • Anteriorly
    • Skin
    • Superficial fascia 
    • External oblique aponeurosis 
    • Internal oblique muscle covers its lateral third
  • Posteriorly
    • Conjoint tendon (Medially)
    • Transversalis fascia (Laterally)
    • Extraperitoneal tissue
    • Parietal peritoneum
Contents of inguinal canal
  1. Spermatic cord
  2. Ilioinguinal nerve
Deep inguinal ring / Internal inguinal ring
It is U shaped condensation formed through the fascia transversalis which lies 1.25cm above the midway between symphysis pubis and anterior superior iliac spin  
Superficial inguinal ring

It is a V shaped defect in the aponeurosis of external oblique muscle which lies 1.25cm above and lateral to the pubic symphysis 

Boundaries of Hesselbach’s triangle

Inferiorly – Inguinal ligament
Laterally – Inferior epigastric artery
Medially – Lateral border of rectus muscle 

Contents of spematic cord

  1. Vessels
    • Testicular artery
    • Cremasteric artery
    • Artery to vas
  2. Nerves
    • Genital branch of genitofemoral nerve
    • Autonomic supply to the testicle
    • Ilioinguinal nerve
  3. Vas deferens 
  4. Pampiniform plexus
  5. Testicular lymphatics
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1 year ago

[…] hernias are the commonest (Inguinal hernia and femoral hernia) To learn the basics of hernia, please read this article.  Groin Hernias There are two types of groin […]