Internal and inguinal region Mathew Wedel, 2015

gut tube

umbilicus gut tube dorsal

visceral gut tube

FOREGUT

dorsal parietal mesentery peritoneum

MIDGUT &

gut visceral tube peritoneum

parietal peritoneum ventral mesentery dorsal mesentery

Aorta visceral peritoneum gut tube

FOREGUT

dorsal parietal mesentery peritoneum

MIDGUT & HINDGUT

gut visceral tube peritoneum

parietal peritoneum ventral mesentery anterior superior iliac spine (ASIS)

pubic tubercles

pubic symphysis anterior superior iliac spine (ASIS) inguinal (Poupart’s ligament

pubic tubercles

pubic symphysis lacuna musculorum

lacuna vasorum together constitute retroinguinal space lateral femoral cutaneous N

femoral N iliacus (lateral) and psoas (medial) MM

lacuna musculorum

lacuna vasorum together constitute retroinguinal space (Cooper’s ligament)

(Gimbernat’s ligament)

lacuna musculorum

lacuna vasorum together constitute retroinguinal space external iliac A&V (become femoral A&V past inguinal lig.)

femoral ring (entrance to femoral canal)

lacuna musculorum

lacuna vasorum together constitute retroinguinal space (ventral mesentery) - single ligamentum teres (obliterated umbilical V) - single umbilicus - single falciform ligament (ventral mesentery) - single ligamentum teres (obliterated umbilical V) - single

umbilicus - single

mediaN umbilical lig. (obliterated ) - single

bladder falciform ligament (ventral mesentery) - single mediaL umbilical lig. (obliterated umbilical A) ligamentum teres - paired (obliterated umbilical V) - single

umbilicus - single

mediaN umbilical lig. (obliterated urachus) - single

internal iliac A (many branches, see future lecture) bladder - paired rectus falciform ligament abdominis (ventral mesentery) M - single mediaL umbilical lig. (obliterated umbilical A) ligamentum teres - paired (obliterated umbilical V) - single

umbilicus - single

mediaN umbilical lig. (obliterated urachus) - single

internal iliac A (many branches, see future lecture) bladder - paired rectus falciform ligament abdominis (ventral mesentery) M - single mediaL umbilical lig. (obliterated umbilical A) ligamentum teres - paired (obliterated umbilical V) - single (inferior epigastric A&V) umbilicus - single - paired mediaN umbilical lig. (obliterated urachus) Contrast the unpaired, - single midline structures associated with the gut tube and urogenital system with the bilaterally paired structures derived from the iliac vessels. internal iliac A (many branches, see future lecture) bladder - paired (Hesselbach’s ligament) - continuous with transversus abdominis M

deep inguinal ring (in lateral umbilical fossa) interfoveolar ligament (Hesselbach’s ligament) - continuous with transversus abdominis M

deep inguinal ring (in lateral umbilical fossa)

testicular A&V (internal spermatic vessels)

ductus deferens deep inguinal ring (in lateral umbilical fossa)

femoral ring (entrance to femoral canal) deep inguinal ring (in lateral umbilical fossa)

femoral ring (entrance to femoral canal) deep inguinal ring Hesselbach’s triangle (in lateral umbilical fossa) () - lies posterior to superficial inguinal ring

supravesical fossa

femoral ring (entrance to femoral canal) deep inguinal ring Hesselbach’s triangle (in lateral umbilical fossa) (medial inguinal fossa) x - lies posterior to superficial inguinal ring

supravesical fossa

femoral ring (entrance to femoral canal) x Cross-section diagram by Rocco Cusari, from: https://commons.wikimedia.org/wiki/File:Inguinal_fossae.PNG#/media/File:Inguinal_fossae.PNG INdirect inguinal – Peritoneal contents pass through , including both deep and superficial rings.

May not involve any tearing of tissues, especially if processus vaginalis is patent.

Accounts for ~75% of inguinal . Ten times more common in males than in females, because of larger inguinal canal. Direct – Peritoneal contents push through tear in abdominal wall, most commonly emerging through superficial inguinal ring.

Necessarily involves tearing the (internal oblique and transversus abdominis aponeuroses). May also tear external oblique aponeurosis if hernia proceeds through supravesical fossa (rare).

Accounts for ~25% of inguinal hernias, mostly in males older than 40. – Peritoneal contents pass through femoral ring, emerge inferior to .

May not involve any tearing of tissues.

More common in females than in males, because of proportionally wider bone structure of female . Triangle of Pain - contains major

Triangle of Doom - contains major vessels Blank version to practice on