Abdomen Flashcards
What are the layers of the anterior abdominal wall (superficial to deep)?
- Skin
- Superficial fascia
- Anterior abdominal wall muscles
- Transversalis fascia
- Extraperitoneal connective tissue
- Peritoneum
What are the layers of superficial fascia in the anterior abdominal wall (superficial to deep)? Describe the layout.
- Superficial fatty layer - fascia of Camper’s
- Deep membranous layer - fascia of Scarpa’s
Above the umbilicus, the superficial fascial layer is only fat. Below the umbilicus, the other two layers arise.
What are the 6 muscles of the anterior abdominal wall?
Anterolateral:
- External oblique
- Internal oblique
- Transversus abdominis
Midline:
- Rectus abdominis
- Pyramidalis
- Cremaster muscle
What is the origin of external oblique?
- Ribs (5-12)
What is the insertion of external oblique?
- Pubic tubercle
- Linea alba
- Iliac crest
What is the origin of internal oblique?
- Iliac crest
- Thoracolumbar fascia
- Inguinal ligament
What is the insertion of internal oblique?
- Ribs (10-12)
- Linea alba
- Pubis
What is the origin of transversus abdominis?
- Thoracolumbar fascia
- Inguinal ligament
- Iliac crest
- Ribs (7-12)
What is the insertion of transversus abdominis?
- Linea alba
- Pubic crest
- Pecten pubis
What are the functions of external oblique, internal oblique, and transversus abdominis?
All: Compress and support abdominal viscera
Obliques only: Flexion and rotation of trunk
What is the origin of rectus abdominis?
- Pubic symphysis
2. Pubic crest
What is the insertion of rectus abdominis?
- Ribs (5-7)
2. Xiphoid process
What is the function of rectus abdominis?
Compression of abdominal viscera
What is the origin of pyramidalis?
- Body of pubis
What is the insertion of pyramidalis?
- Linea alba
What is the function of pyramidalis?
Tenses linea alba
What is the origin of cremaster?
- Internal oblique muscle
2. Inguinal ligament
What is the insertion of cremaster?
- Crest of pubis
2. Pubic tubercle
What is the function of cremaster?
Moves the testes
What is the rectus sheath?
Aponeurotic sheath formed by the fusion of the aponeuroses of external oblique, internal oblique, and transversus abdominis.
What are the muscular contents of the rectus sheath?
- Rectus abdominis
2. Pyramidalis
What are the vascular and nerve contents of the rectus sheath?
- Inferior epigastric
- Superior epigastric
- Lower 6 intercostal nerves
Describe the walls of the rectus sheath above the arcuate line.
The anterior layer of the rectus sheath above the arcuate line contains the aponeuroses of the external and internal obliques. The posterior layer of the rectus sheath contains the aponeuroses of the internal oblique and transversus abdominis.
Describe the walls of the rectus sheath below the arcuate line.
The rectus sheath below the arcuate line contains the aponeuroses of the external oblique, internal oblique, and transversus abdominis. The rectus abdominis is not within the rectus sheath; it is in contact with the transversalis fascia.