Internal abdominal wall and inguinal region Mathew Wedel, 2015 gut tube umbilicus gut tube dorsal mesentery visceral peritoneum gut tube FOREGUT dorsal parietal mesentery peritoneum MIDGUT & HINDGUT 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 ligament (Poupart’s ligament pubic tubercles iliopectineal arch 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 pectineal ligament (Cooper’s ligament) lacunar 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 falciform ligament (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 urachus) - 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 lateral umbilical fold (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 interfoveolar ligament (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) supravesical fossa femoral ring (entrance to femoral canal) deep inguinal ring Hesselbach’s triangle (in lateral umbilical fossa) (medial inguinal 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 hernia – Peritoneal contents pass through INguinal canal, including both deep and superficial rings. May not involve any tearing of tissues, especially if processus vaginalis is patent. Accounts for ~75% of inguinal hernias. Ten times more common in males than in females, because of larger inguinal canal. Direct inguinal hernia – Peritoneal contents push through tear in abdominal wall, most commonly emerging through superficial inguinal ring. Necessarily involves tearing the conjoint tendon (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. Femoral hernia – Peritoneal contents pass through femoral ring, emerge inferior to inguinal ligament. May not involve any tearing of tissues. More common in females than in males, because of proportionally wider bone structure of female pelvis. Triangle of Pain - contains major nerves Triangle of Doom - contains major vessels Blank version to practice on .