Lecture 2 Flashcards
What forms the superior boundary of the abdomen?
Diaphragm, inferior thoracic aperture
What forms the inferior boundary of the abdomen?
Iliac crest, inguinal ligament, pelvic inlet
What forms the posterior boundary of the abdomen?
Lumbar vertebral column, psoas major, quadratus lumborum, (abdominal wall muscles)
What forms the lateral and anterior boundaries of the abdomen?
Abdominal wall muscles
List the layers of the abdominal wall from the most superficial to most deep.
Skin Camper's Fascia Scarpa's Fascia External Oblique Internal Oblique Transversus Abdominis Transversalis Fascia (Extraperitoneal Fascia) Parietal Peritoneum
What are the two layers of the superficial fascia?
Camper’s Fascia and Scarpa’s Fascia
In the abdomen, where is the superficial fascia similar to that found elsewhere in the body?
Above the umbilicus
What happens to the superficial fascia below the umbilicus?
It divides into 2 layers: Camper’s fascia and Scarpa’s fascia
Describe the two layers of the superficial fascia. Which layer is more deep?
Camper’s: thick, yellow, fatty layer all over the abdomen
Scarpa’s: thinner, orange, membranous layer continuous with various other fascia (deep)
What are the functions of the muscles of the abdominal wall? What other feature aids the ability to move?
Provide stability and allow abdominal viscera to move. No bony structures between ribs and pelvis also allows movement.
What are the muscles of the abdominal wall?
Rectus Abdominis
External Oblique
Internal Oblique
Transversus Abdominis
What is the origin of Rectus Abdominis?
Pubic Tubercle, Crest, and Symphysis
What is the insertion of Rectus Abdominis?
Costal cartilages of ribs 5-7 and xiphoid process
What are the actions of Rectus Abdominis?
- Flex trunk
- Support/compress abdominal wall (Secondary respiratory muscles for forcing expiration)
What is the nerve supply of the Rectus Abdominis?
Anterior rami of thoracic spinal nerves
What is the origin of the external oblique muscle?
Ribs 5-12
What is the insertion of the external oblique muscle?
Iliac crest and linea alba via aponeurosis
Where does the aponeurosis of the external oblique stretch from and to?
From xiphoid process to pubic symphysis
What does the lower border of external oblique form?
Inguinal ligament
What are the actions of external oblique?
- Flex trunk (both)
- Turn to opposite side/bend trunk to same side (single)
What is the nerve supply of external oblique?
Anterior rami of thoracic spinal nerve
What is the fibre direction of external oblique?
Infero-medial
What is the origin of internal oblique?
Thoracolumbar fascia, inguinal ligament and iliac crest
What is the insertion of internal oblique?
Ribs 9-12
What are the actions of the internal oblique muscles?
- Flex trunk (both)
- Bend and turn trunk to same side (single)
What is the nerve supply of internal oblique?
Anterior rami of thoracic spinal nerves (some L1)
What is the fibre direction of internal oblique muscles?
Supero-medial
What is the origin of transversus abdominis?
Thoracolumbar fascia, iliac crest, inguinal ligament, costal cartilage of ribs 7-12