Medical Articles

Abdominal Wall & Diaphragmatic Hernias

Abdominal Wall Hernias

Definition: Protrusion of intra-abdominal tissue through a fascial defect in the abdominal wall External hernia typically consist of:

  • Neck ⇒ the opening in the abdominal wall fascia
  • Sac ⇒ of peritoneum
  • Contents ⇒ Organs (bowel, ovaria, bladder) or other tissue (omentum)
  • Covering ⇒ (skin, subcutaneous tissue)

Important terminology

  • Reducible hernia ⇒ contents of the sac can return to the abdominal cavity.
  • Irreducible (incarcerated) hernia ⇒ contents of the sac cannot return to abdominal cavity (narrow neck)
  • Obstructed hernia ⇒ obstruction of flow of bowel contents.
  • Strangulated hernia ⇒ compromise to blood supply of contents
  • Richter’s hernia ⇒ only part of the circumference of the bowel is incarcerated or strangulated.
  • Littre hernia ⇒ a Meckel’s diverticulum forms part of contents.
  • Sliding hernias ⇒ wall of a viscus forms part of the hernia sac (i.e. Bladder, ovary, sigmoid, cecum)
  • Rolling hernia ⇒ sac consists only of peritoneum.

Inguinal Hernia

Most common external hernia (±75%) Adults: 10-15% - M:V 12:1 Inguinal (direct + indirect) Femoral – more common in females

Inguinal Canal

  • Tube ± 5cm long from internal opening to external opening
  • Internal opening – hole in fascia transversalis, midway between SIAS and pubic tubercle, above inguinal ligament.
  • External opening – hole in external oblique aponeurosis superolateral to pubic tubercle.

Anatomic Relationships:

Fascia transversalis ⇒ Posterior
External oblique ⇒ Anterior
Inguinal ligament ⇒ Inferior

Falx ingenialis/Conjoined tendon is anterior laterally, superior in the middle and posterior medially (Conjoined tendon – fusion of the internal oblique and transversus abdominus muscle)

Hernia sac of an indirect inguinal hernia – patent processus vaginalis. Found Antero-medial to spermatic cord.

Hesselbach’s triangle

  • Inferior epigastric vessels lateral
  • Lateral edge rectus abdominus muscle medial
  • Inguinal ligament inferior

Area of weakness – direct hernia originates.
Direct hernia situated medial to indirect hernia.
Combination = pantaloon hernia

Femoral Canal

  • Lacunar (Gimbernat) ligament medial
  • Inguinal (Poupart) ligament superior
  • Ileopectined ligament (Cooper) inferior
  • Femoral vein lateral

Origin of femoral hernia (and form the narrow unyielding neck ⇒ high incidence of strangulation)

Clinical Presentation

Mass in the groin

Occours or increases in size with increased abdominal pressure May present with complications

Bowel obstruction

Indirect lnguinal Hernia

  • Congenital (processus vaginalis not obliterated), presents later in life
  • Travels obliquely in inguinal canal to scrotum
  • Reduces obliquely upwards to internal opening
  • Internal opening is the neck and pressure here keeps the hernia reduced.

Direct inguinal hernia


  • Weakness in transversalis fascia in Hesselbach’s triangle
  • Increased intra-abdominal pressure
  • COPD, prostatic hyperplasia
  • Colon carcinoma, ascites

Protrudes directly through Hesselbach’s triangle Reduces directly (straight), cannot be controlled by pressure at internal opening.

Femoral hernia

  • Acquired
  • More common in females
  • Often asymptomatic until it strangulates
  • Prone to strangullatiion

Differential diagnosis of a groin mass

  • Hernia
    • Indirect
    • Direct
    • Femoral
  • Testicle ⇒ undecended, retractile, torsion of the testis
  • Lymph nodes
  • Lipoma
  • Varices of the sapheno-femoral junction
  • Aneurysm (femoral)
  • Abscess


  • Irreducible
  • Bowel obstruction
  • Strangulation

Management of groin hernias

1) Surgical repair

  • All hernias should be surgically repaired unless there are specific contra-indications.
  • Preferably elective repair
    • Emergency repair if presents with complication
  • Many surgical options
    • open and laparoscopic
    • various techniques
      • Pure tissue repair
      • Pure prosthetic repair
      • Combination

Surgical repair (continued)

Remove or reduce the hernia sac Repair/strengthen normal anatomy (mesh or permanent suture material) Strangulation – resect infarcted tissue

Local or general anaesthesia

Wound sepsis
Damage to cord structures
cutaneous nerve damage

Management (continued)

  1. Truss
    Prefferably avoided Old,, chronically ill patient, direct hernia which easily reduces or patient refuses surgery

Other abdominal wall hernias

Umbilicall Hernia

  • Congenital
    • Through umbilical ring

Para-umbilical hernia


  • Outside umbilical ring
  • Female
  • Increased intra-abdominal pressure
  • Narrow elliptical neck ⇒ strangulation

Epigastric Hernia

  • Linea alba (in epigastrium) - foramina where cutaneous nerves and blood vessels penetrate
  • Young men
  • Preperitoneal fat (Not peritoneal sac)
  • Neck narrow ⇒ strangulate

Incisional Hernia

  • Previous surgical scar
  • Etiology
    • Poor wound healing
    • Increased wound tension
    • Poor technique
  • Problems
    • Cosmetic
    • Functional
    • Pain
    • Strangulation
    • Recurrence

Special hernia’s

  • Rare
  • Littre’s hernia
  • Spigelian herna
  • Lumbar hernia (Grynfeltt, Petit)
  • Obturator hernia
  • Perineal hernia
  • Siatic hernia

Diaphragmatic hernias

Definition: Herniation of abdominal content through
a defect in the diaphragm into the thoracic cavity.
Congenital - Bochdalek
Acquired - Traumatic
Hiatal ~ Sliding
Para-esophageal (Rolling)

  • Bochdalek hernia – neonatal emergency see Ped. Surg.Notes.
  • Morgagni hernia (parasternal or anterior diaphragmatic hernia).
  • Failure of fusion of sternal and costal elements of diaphragm.
  • Presents later in life:
    • Incidental finding on CXR (asymptomatic)
    • Vague upper abdominal complaints/retro-sternal pain
    • Emergency – bowel obstruction/strangulation
    • Surgical repair once diagnosed.

Traumatic diphragmatic hernia

Penetrating or blunt trauma ⇒ Chronic established hernia – Stab
⇒ Hernias due to blunt trauma or due to GSW are usually found at early surgery
⇒ 95% left - Right handed assailants - Liver protects the right diaphragm
⇒ Presents months to years after initial injury with bowel obstruction/strangulation of contents
⇒ Mortality 50% in cases of strangulated colon in the chest

Traumatic diaphragmtic hernia

Diagnosis: CXR

  • Bowel gas and fluid levels in chest
  • Stomach as content of hernia ⇒ nasogastric tube in chest
  • barium meal
  • barium enema

Treatment Prevention

  • Urgent surgical repair
  • High index of suspicion in wounds between the nipple line and the costal margin especially on the left

Hiatus Hernia

  • Herniation of part of the stomach through the oesophageal hiatus into the thorax
  • Classification
    • Sliding-type
    • Rolling-type (para-oesophageal)
    • Combination

Anatomy of a hiatus hernia

Rolling hernia EGjunction under diaphragm

Sliding-hernia EGjunction above diaphragm

Hiatus hernia

Sliding Hernia

  • Most common (95%)
  • GERD

Rolling Hernia

  • rare (5%)
  • reflux not a problem
  • Mechanical problems ⇒

Incarceration/stasis/ulceration/perforation ⇒ Symptoms – asymptomatic to vague left upper quadrant discomfort, dysphagia, chest pain

Para-esophageal hernia

  • Diagnosis – CXR: air fluid level behind cardiac shadow
  • Management Surgical repair: open or laparoscopic
    • Reduction of hernia
    • Closure of esophageal hiatus ± fundoplication