Abdomen & Anterior Abdominal Wall Learning Objectives Flashcards
Explain the function of the abdomen and its boundaries
Function: flexible container for the abdominal organs
Boundaries
- Anterior: abdominal wall
- Posterior: vertebral column
- Superior: diaphragm
- Inferior: pelvic inlet
Explain the functions of the anterior abdominal wall
Functions:
- Support the trunk
- Support the abdominal viscera
- Manage intra-abdominal pressure during respiration
- Move the trunk and maintain posture
Describe the organization of the greater and lesser sacs
Greater sac: “main abdominal cavity”
Lesser sac: “omental bursa”; diverticulum
- Posterior to stomach
Describe the organization of the mesenteries
Mesentery = double layer of peritoneum; provides conduit for neurovascular supply b/t organ and body wall
Peritoneal layers:
- visceral (innermost)
- parietal
Peritoneal ligaments of the greater omentum
Gastrophrenic ligament
Gastrosplenic ligament
Gastrocolic ligament
Peritoneal ligaments of the lesser omentum
Hepatogastric ligament
Hepatoduodenal ligament
Falciform ligament
Peritoneal ligament
Attaches liver to posterior surface of anterior abdominal wall
Inferiorly encloses the round ligament of the liver
Intraperitoneal
Enclosed by visceral peritoneum
Suspended by mesenteries
Primarily retroperitoneal
Kidneys
Suprarenal glands
never had mesentery, posterior to peritoneal cavity
Secondarily retroperitoneal
Duodenum (desc, horiz, ascend)
Colon (ascend, desc)
Pancreas
Rectum (upper 2/3)
were previous intraperitoneal, but mesentery fused during development
Explain the layers of the rectus sheath above the arcuate line
upper 2/3
Anterior rectus sheath: external oblique and internal oblique
Posterior rectus sheath: internal oblique and transversus abdominis (and transversalis fascia however not RS)
Explain the layers of the rectus sheath below the arcuate line
lower 1/3
Anterior rectus sheath: external oblique, internal oblique, transversus abdominis
Posterior (not considered rectus sheath): transversalis fascia
Explain the significance of the arcuate line
Demarcates the transition b/t the aponeurotic posterior rectus sheath (internal oblique and transversus abdominis) and the transversalis fascia
- When IO and TA transition to anterior rectus sheath
Inferior epigastric vessels perforate the rectus abdominis
Describe the anatomy of the inguinal canal including its contents in both males and females
4 cm long, parallel to inguinal ligament
Openings:
Deep inguinal ring
Superficial inguinal ring
Contents:
- ilioinguinal n.
- male: spermatic cord
- female: round ligament of uterus
Inguinal canal boundaries
Floor: inguinal ligament reinforced medially by lacunar ligament
Anterior wall: external oblique (aponeurosis) reinforced laterally by internal oblique
Posterior wall: transversalis fascia reinforced by conjoint tendon
List the layers of the anterior abdominal wall from superficial to deep
Skin
Camper’s fascia (fatty layer)
Scarpa’s fascia (membranous layer)
External abdominal oblique m.
Internal abdominal oblique m.
Transversus abdominis m.
Transversalis fascia
Extraperitoneal adipose
Parietal peritoneum
Describe the innervation of the skin of the abdomen via T7-T12 spinal nerves
Innervation corresponds with dermatomal striping pattern; no plexus
T7-11: thoracoabdominal nn.
T12: subcostal n.
T4: nipple
T6: xyphoid process
T10: umbilicus