Friday, March 20, 2015

Inguinal canal

Posted by Pulasthi Senaratna

A 21 year old man has an inguinal hernia and is undergoing a surgical repair. As the surgeons approach the inguinal canal they expose the superficial inguinal ring. Which of the following forms the lateral edge of this structure?

  

A.

Inferior epigastric artery

  

B.

Conjoint tendon

  

C.

Rectus abdominis muscle

  

D.

External oblique aponeurosis

  

E.

Transversalis fascia

 

The external oblique aponeurosis forms the anterior wall of the inguinal canal and also the lateral edge of the superficial inguinal ring. The rectus abdominis lies posteromedially and the transversalis posterior to this.

 

Inguinal canal

Location

  • Above the inguinal ligament
  • The inguinal canal is 4cm long

Boundaries of the inguinal canal

Floor

  • External oblique aponeurosis
  • Inguinal ligament
  • Lacunar ligament

Roof

  • Internal oblique
  • Transversus abdominis

Anterior wall

External oblique aponeurosis

Posterior wall

  • Transversalis fascia
  • Conjoint tendon

Laterally

  • Internal ring
  • Fibres of internal oblique

Medially

  • External ring
  • Conjoint tendon

Contents

Males

Spermatic cord and ilioinguinal nerve

As it passes through the canal the spermatic cord has 3 coverings:

  • External spermatic fascia from external oblique aponeurosis
  • Cremasteric fascia
  • Internal spermatic fascia

Females

Round ligament of uterus and ilioinguinal nerve

 

Related anatomy of the inguinal region


The boundaries of Hesselbachs triangle are commonly tested and illustrated below:

clip_image004

 

The image below demonstrates the close relationship of the vessels to the lower limb with the inguinal canal. A fact to be borne in mind when repairing hernial defects in this region.

clip_image006