Anterolateral abdominal wall & Inginal region Flashcards
What nerve innervates the cremaster muscle?
Gential branch of the genitofemoral nerve
Where does the cremasteric artery arise from?
Inferior epigastric artery
How does a direct inguinal hernia arise?
- Weakness in the anterior abdominal wall in an inguinal triangle (thin inguinal falx or widened superior inguinal ring)
- The intestines leave the abdominal cavity through the superficial inguinal ring
- Lies outside of the spermatic cord
What layers of the abdominal wall contain/are involved in the direct inguinal hernia?
Happens at the Hessalback triangle
Contained by the Peritoneum and transversalis fascia
Boundaries of the Hessalbach triangle
Base: Inguinal ligament
Apex: Inferior epigastric vessels meets the rectus abdominus muscle
Medial: Rectus abdominus
Lateral: Inferior epigastric vessels
Floor: Conjoint tendon &Transversalis fascia
What nerve innervates the anterior scrotum?
Ilioinguinal nerve
What innervates the posterior scrotum?
Perineal branch of pudendal nerves
Why does indirect herniation occur?
The processes vaginalis persists after the sperm or ovaries descend the abdominal wall (through gubernaculum)
What happens in indirect herniation?
Loop of small intestine passes through the deep inguinal ring which has not closed in the processes vaginalis through the superficial into the scrotal sac
Neck of the hernia sac lies lateral to inferior epigastric vessels
What is the tunica vaginalis?
It is the remnant of the processes vaginalis that surrounds the testes forming serous membrane :
- Parietal layer covers the inside of the internal spermatic fascia
- Visceral layer covers the testes and epididymis.
What is the Arcuate line?
This is the point where the transversus abdmonius passes through the rectus abdominus muscles and forms three layers of muscle in the anterior part of the rectus abdominus leaving only the transversalis fascia.
What enters the arcuate line?
Inferior epigastric artery
Anastamoses at the umbilicus
Where does the neurovascular plane run?
Between the tranversus abdminus and internal oblique muscles
Musculophrenic artery
Branch of the internal thoracic artery
Supplies anterolateral surface of the diaphragm
Supplies anterior and posterior hypochondriac
Layers of the Anterolateral abdominal wall
- Skin
- Camper’s fatty fascia
- Scarpa’s fascia
- External Oblique
- Internal Oblique
- Transversus Abdmonious
- Transversalis fascia
- Extraperitoneal fasica
- Peritoneum (Parietal layer)
What are the two layers of the peritoneum?
Parietal peritoneum (Lines the abdominopelvic wall)
Visceral Peritoneum (Lines the organs)
Intraperitoneal organs?
They are completely covered by the visceral peritoneum
Liver, Stomach, small intestines, spleene
Extraperitoneal or Retroperitoneal organs?
These are partially surrounded by the visceral peritoneum
Kidneys & Adrenal gland
Descending and Ascending colon
Pancreas
Part of duodenum
Urinary bladder
Why is the duodenum a retroperitoneal organ?
During development the stomach turns 90 degrees around craniocaudal axis this turn bends the duodenum into a “C” shape.
It then moves to the right and adheres to the posterior wall
What contributes to the formation of lesser sac?
The rotation of the stomach and the fusion of the duodenum to the body wall contributes to lesser sac of the peritoneum
How is the greater omentum formed during development?
The stomach begins as a tube with two attachments to the abdominal body walls anteriorly and posteriorly.
As the stomach rotates it forms a lesser sac and a greater sac
The lesser sac attaches from the greater curvature of the stomach and will grow to give rise to the greater omentum