Abdominal Wall Flashcards
What is the area of the abdominal wall? (borders)
the area extending from the costal arch to the pelvis, and from the ventral border of the epaxial muscles to the linea alba (midventral midline)
What are the four quadrants of the abdominal wall on each side?
- craniodorsal quadrant
- caudodorsal quadrant
- cranioventral quadrant
- caudoventral quadrant
What are the regions of the cranial abdominal region?
- Xiphoid region
- Hypochondriac region (left and right)
What are the regions of the middle abdominal region?
- Umbilical region
- Lateral abdominal region (left and right)
What are the regions of the caudal abdominal region?
- Pubic region
- Inguinal region (left and right)
What innervates the abdominal wall? Where are they located?
Ventral branches of spinal nerves T13 - L5
- Lateral cutaneous branches located between skin and external abdominal oblique m.
- Medial branches seen between internal abdominal oblique and transversus abdominis mm.
What are the names of the ventral branches of spinal nerves L1 - L4?
L1 - Cranial iliohypogastric
L2 - Caudal iliohypogastric
L3 - Iliolumbar
L4 - Lateral cutaneous femoral
What is the artery of note in the caudodorsal quadrant of the abdomen? (Blood supply to abdominal wall)
deep circumflex iliac a.
What is the artery of note in the craniodorsal quadrant of the abdomen? (Blood supply to abdominal wall)
Phrenicoabdominal a.
What are the arteries of note in the caudoventral quadrant of the abdomen? (Blood supply to abdominal wall)
- Caudal epigastric and caudal superficial epigastric aa.
What are the arteries of note in the cranioventral quadrant of the abdomen? (Blood supply to abdominal wall)
- cranial epigastric and cranial superficial epigastric aa.
How is the mammae supplied with blood?
by the cranial and caudal superficial epigastric arteries
The Internal thorasic a. gives rise to the ______1______ which gives rise to _______2_______
1 - cranial epigastric a.
2 - cranial superficial epigastric a.
What does the external pudendal a. give rise to?
caudal superficial epigastric a.
What is the origin of the external abdominal oblique?
ribs and thoracolumbar fascia
What is the insertion of the external abdominal oblique?
aponeurosis (sheet-like tendon) of this muscle imparts a broad attachment of the muscle at the linea alba (white line, mid-ventral raphe)
What is the most superficial of the abdominal muscles?
the external abdominal oblique
The ventral border of the aponeurosis of the external abdominal oblique forms what?
the inguinal ligament
What does the inguinal ligament attach to?
attaches to the iliopubic eminence and the prepubic tendon
There are openings in the external abdominal oblique for what? (3)
- Vascular lacuna (femoral vv.)
- Muscular lacuna (iliopsoas m.)
- Superficial inguinal ring (vaginal process/tunic, genitofemoral nerve, external pudendal a. and v., cremaster m.)
What lies deep to the external abdominal oblique?
internal abdominal oblique
What is the orientation of the fibers of the external abdominal oblique?
caudodorsal orientation (craniodorsal -> caudoventral)
What is the orientation of the fibers of the internal abdominal oblique?
cranioventrally (caudodorsal -> cranioventral)
What is the origin of the internal abdominal oblique?
tuber coxae, inguinal ligament, and thoracolumnar fascia
What is the insertion of the internal abdominal oblique?
inserts via wide aponeurosis on the costal arch, rectus abdominis, linea alba, and prepubic tendon
What is the deepest abdominal muscle?
transversus abdominis
What is the origin of the transversus abdominis?
process of the lumbar vertebrae and thoracolumnar fascia
What is the insertion of the transversus abdominis?
linea alba
What is the rectus abdominis? (action)
flexor of the vertebral column
- it is the six pack muscle due to distinct transverse tendinous insertions
What is the origin and insertion of the rectus abdominis?
extends from the prepubic tendon to the sternum
What forms the rectus sheath?
the aponeuroses of the abdominal oblique muscles and the transversus abdominis m.
What is the structure of the rectus sheath near the pubis?
all three aponeuroses’ lie superficial to the rectus abdominis
What is the structure of the rectus sheath caudal to the umbilicus?
the aponeuroses of the transversus abdominis m. lies deep to the rectus abdominis
- others lay above the rectus abdominis
What is the structure of the rectus sheath cranial to the umbilicus?
the aponeuroses of the internal abdominal oblique splits and forms a sleeve around the rectus abdominis m.
- transversus abdominis lies underneath, the external abdominal oblique lies on top
What is the inguinal canal?
a flattened canal between the deep and superficial inguinal rings
What passes obliquely through the inguinal canal?
the vaginal process (female) and vaginal tunic/spermatic cord (male)
What is the superficial inguinal ring?
the slit-like opening in the ventral aspect of the aponeurosis of the external abdominal oblique m.
What are the boundaries of the deep inguinal ring?
- Cranial boundary is the ventral (caudal) border of the internal abdominal oblique m.
- Medial boundary is the rectus abdominis m.
- Caudal boundary is the inguinal ligament
What is used to access the cecum in the horse and cattle?
the RIGHT paralumbar fossa
What is used to access the rumenin the cow/bull?
the LEFT paralumbar fossa
What is the origin of the internal abdominal oblique m. in the horse?
solely from the tuber coxae
What is the origin of the internal abdominal oblique in the bull/cow?
the transverse processes of lumbar vertebrae and thoracolumnar vertebrae as well as the tuber coxae
What supports the weight of the abdominal viscera?
the tunica abdominis
What type of tissue makes up the tunica flava abdominis?
elastic tissue - often yellowish in color
Where is the tunica flava abdominis thickest and why?
thickest ventrally where fibers of the fascia exchange fibers with the aponeurosis of the external abdominal oblique
What is the linea alba formed by?
the unity of the left and right aponeuroses of abdominal mm. at the midline
What is the linea alba strengthened by caudally?
longitudinal fibers
What forms the pubic tendon?
the combination of the linea alba with insertion tendons of the left/right rectus abdominis mm. -> forms a broad plate
What is susceptible to rupture in the pregnant mare?
prepubic tendon
The accessory ligament of the femoral head extends from What in the horse?
the prepubic tendon
What is the accessory ligament (of the femoral head) located deep to as it extends through the acetabular notch?
the transverse acetabular ligament
Where does the accessory ligament of the femoral head insert?
on the femoral head adjacent to the ligament of the head of the femur
What is the action of the accessory ligament of the femoral head?
- tensed by weight of the abdomen and this tension helps secure femoral head in place
- limits movement at the coxofemoral joint; prevents side kicking
What are the borders of the paralumbar fossa?
Base: along the tips of the lumbar transverse processes
Cranioventral border: last rib
Caudoventral border: ridge formed by part of the internal abdominal oblique muscle that extends from the tuber coxae to the ventral end of the last rib of the ox
Where is the paralumbar fossa and what does it look like?
a sunken triangular region caudal to the last rib
What is an important palpable landmark in the horse when locating the paralumbar fossa?
the tuber coxae