AAW: Inguinal Canal Flashcards
Describe the formation of the Inguinal Canal
Passage of Processus vaginalis which is a peritoneal process through layers of lower part of Anterior Abdominal Wall during intrauterine life
Site of inguinal canal
Above the medial 1/2 of Inguinal Ligament, between Deep(internal) inguinal ring & Superficial(external) inguinal ring
length of inguinal Canal
4cm long
Direction of inguinal Canal
Downwards forewards and medial
Beginning of Inguinal Canal is formed by
Deep (Internal) Inguinal Ring
End of Inguinal Canal is formed by
Superficial (External) Inguinal RIng
Shape of Deep (Internal) inguinal Ring
Oval
Site Of Deep (internal) inguinal Ring
in Fascia Transversalis, 1/2 inch above mid-inguinal point & Lateral to inferior Epigastric A
Extension of Deep (internal) inguinal Ring
Internal Spermatic Fascia
Shape of Superficial (external) Inguinal Ring
Triangular
Site of Superficial (external) Inguinal Ring
It’s an opening of Aponeurosis of External Abdominal Oblique , located Above and medial to pubic tubercle
Describe the boundaries of Superficial (external) inguinal Ring
- Medial Crus: attached to Symphysis pubis & intercrural fibers
- Lateral Crus: attached to Pubic tubercle & Intercrural fibers
- Base: fromed by pubic crest
Extensions of Margins of Superficial (External) inguinal ring
External Spermatic Fascia
which structure passes through Superficial (external) inguinal Ring but not Deep (internal) inguinal ring/ enters inguinal canal not through deep (internal) inguinal Ring
Ilioinguinal N, it perices the fleshy fiber of Internal Abdominal Oblique & enters the canal
Anterior wall of inguinal Canal
- Whole length: external Abdominal oblique
- Lateral 1/2: + lower fleshy fiber origin of Internal Abdominal Oblique
Posterior wall of Inguinal Canal
- Along whole length: Fascia transversalis
- medial 1/2: +Conjoint tendon
- Medial 1/4: + Reflected part of inguinal Ligament (in front of conjoint tendon)
Lateral 1/2 of post. wall of canal = fascia transversalis only
Roof of Inguinal Canal
Arch of lower fleshy part of Internal Abdominal Oblique & Transversus Abdominus
Floor of Inguinal Canal
Upper concave surface of Inguinal Ligament
* Medial 1/2: + lacunar ligament
Enumerate contents of Inguinal Canal
- Spermatic cord and its coverings
- Ilio-inguinal N
Explain why inguinal canal is a weak area
- Presents of Inguinal rings (internal & external)
- presence of area in Anterior wall with no reinforcement (medial 1/2 formed by external oblique aponeurosis only)
- Presence of Area in posterior wall with no reinforcement (lateral 1/2 formed only by fasica transversalis)
- Spermatic cord pasess between the layers of Abdominal wall
Explain how Weakness of Inguinal Canal is compensated
- Shutter mechanism: Contraction of internal abdominal oblique during coughing/straining, causing it to lose concavity and close the canal
- Valvular mechanism: the 2 rings ar not in front of each other
- Increased intra-abdominal pressure: forces posterior wall against anterior wall,closing the external inguinal ring
- superficial (external) ring is compensated by Conjoint tendon & reflected part of inguinal ligament at posterior wall of canal
- Deep (internal) ring is compensated by lower fleshy origin of internal abdominal oblique in anterior wall of canal
- Intercrural fibers
- cremastric reflex
Medial wall of Inguinal triangle (hasselbach’s triangle)
Lateral border of rectus abdomius
Lateral wall of Hasselbach’s triangle (inguinal)
Inferior Epigastric vessels
Inferior border of Hasselbach’s (inguinal) triangle
Inguinal ligament
Floor of Hasselbach’s (inguinal) Triangle
- Parietal peritoneum
- Extra-peritoneal tissue & fat
- Fascia transversalis
- Conjoint tendon & reflected part inguinal ligament
Hasselbach’s (inguinal) Triangle is divided into medial and lateral subdivisions by
Obliterated umblilical A (lateral Umbilical ligament)