Lecture 9 DA Flashcards
What are the two fascia of the skin in the abdomen?
Camper’s fascia - more fatty and superficial
Scarpa’s fascia - more membranous and deep
How is the perotineum of the abdomen different to the thoracic perotineum?
It has more than one site where it leaves the abdominal wall. This is known as mesentery (like the pulmonary ligament).
What structures does the abdominal muscles attach to?
To the costal margin superiorly.
To the iliac crest, ASIS and pubic crest/tubercle inferiorly.
How do the three abdominal muscle layers attach to the costal margin?
The most superficial overlaps with the costal margin.
The middle layer is edge-to-edge with the costal margin.
The deepest underlaps the costal margin.
How do the abdominal muscles change as you move medially?
They are fleshy laterally, and aponeurotic medially.
Describe the three layers of abdominal muscles.
Superficial most - external oblique, front pockets muscle
middle - Internal oblique, back pockets muscle
deepest - transversus abdominus, runs horizontally
What is the linea alba?
The abdominal muscles are aponeurotic medially, and this contributes to the linea alba, found at the midline.
Where does the external oblique attach inferiorly?
To the anterior half of the iliac crest, to the ASIS, and to the pubic crest.
It has a free inferior edge, bordered by the inguinal ligament.
Where does the internal oblique attach inferiorly?
To the iliac crest, to the ASIS, and to the lateral two thirds of the inguinal ligament.
Free inferior edge turns inward, providing attachment of lowermost fibres to the inguinal ligament.
Do the lowermost fibres of the internal oblique contribute to the linea alba?
No, they arch upward and back down to attach to the pubic crest.
What is the relationship between the transversus abdominus muscle, and the diaphragm?
They are continuous with each other/on the same plane.
Where does the transversus abdominus muscle attach inferiorly?
To the iliac crest, to the ASIS, and to the lateral third of the inguinal ligament. Fibres also arch upward and down to the pubic crest as with internal oblique. The two form a conjoined tendon, which inserts to the pubic tubercle.
Where does the rectus abdominus muscle insert and attach?
It arises from the pubic crest, and inserts to the costal margin, overlapping it. It attaches to ribs 5, 6, & 7.
Describe the structure of rectus abdominus, and why its beneficial.
It has transverse aponeuroses, called tendinous inscriptions. There are typically 3: One at the umbilicus One between at the xiphisternum One between umbilicus and xiphisternum This makes the muscle much stronger.
What else is formed alongside the linea alba?
The rectus sheath. As the aponeuroses of the internal/external oblique and transversus abdominus travel medially, they travel anterior and posterior to the rectus abdominus, enveloping it in a thick sheath before forming the linea alba.
