Anterior Abdominal Wall Flashcards
Transverse Planes and what level, organs they run through? Transpyloric plane
(L1 level)
-level of the gall bladder funder, pylorus, pancreatic neck, SMA orgin, hepatic portal vein, root of transverse mesocolon, hila of kidneys
Transverse Planes and what level, organs they run through? Subcostal plane
- Passes inferior border of 10th costal cartilage
- level of transverse cartilage
Transverse Planes and what level, organs they run through? Transtubercle plane
- Between iliac tubercles
- Level of iliocecal junction
Transverse Planes and what level, organs they run through? Interspinous plane
- Between ASIS
- Level of appendix, sigmoid colon
What is the abdominopelvic cavities? and what is it lined by?
Includes the abdomen and pelvis:
- between thoracic diaphragm and pelvic diaphragm
- can extend as high as 4th intercostal space
- Abdomen separated from pelvis by imaginary border of pelvic inlet
- Greater pelvis (above pelvic inlet)
-Walls mostly bone, muscle and CT
Lined by peritoneum
Also called Peritoneal cavity
what is the outer layer of the Anteriolateral abdominal wall, and what are its boundaries
Boundaries:
- Upper 7-10 costal cartilages
- Lower inguinal ligament and pelvic bones
Outer layer:
- Skin, campers fascia and scarpas fascia
- Aponeurosis-tough, relatively thick because its made of several layers (overlies/envelops rectus abdominis forming rectus sheath)
What is Campers Fascia?
What is Scarpas Fascia
Both are parts of the integument
Campers fascia: fatty layer of superficial fascia
Scarpas fascia: membranous underlying CT layer of superficial fascia
- continuous with colles fascia of the perineum but fused with the fascia lata of lower limb
- Fluid cannot go from abdominal wall into leg but could flow into or out of superficial perineum
Orgin, insertion, Innervation, and action of the External Oblique Muscle
Runs in downward medial direction
Interdigitates with serratus anterior
Orgin: Outer surface of lower 6 ribs
Insertion: aponeurosis and linea alba, anterior iliac crest and pubic tubercle
- lower portion is rolled under to make inguinal ligament that is attached to ASIS and the pubic tubercles. makes opening of superficial inguinal ring
- some also reflected under to make the lacunar ligament
Innervation: ventral rami of T7-12 or intercostal nerves
Action: Compress abdomen and increase intra abdominal pressure; move trunk and retain posture
most external of the abdominal muscles
Origin, insertion, Innervation, and action of the internal oblique muscle
Runs 90 degrees from external oblique muscle
Fibers run upwards
Origin: iliac crest and some of thoracolumbar fascia
Insertion: lower 10-12 ribs, aponeurosis, linea alba and pubic crest, lower parts make part of conjoint tendon (inguinal falx)
- some fibers follow spermatic cord to make cremaster muscle
- Aponeurosis part splits to encompass rectus muscle in upper 3/4
innervated: by T7-12 and L1
Action: compresses and supports viscera, lateral flexes and rotates
Origin, insertion, aponeurosis, innervation, and action of the Transverse abdominus muscle
Runs transverso-medially except for some running toward pubic crest (to contribute to conjoint tendon)
- straight accross
- Most deep of the abdominal wall muscles
Origin: lower 7-12 ribs, thoracolumbar fascia, iliac crest, and some even off upper inguinal ligament
Insertion: Linea alba, pecten pubis, and pubic crest
-Aponeurosis contributes to rectus sheath
Innervation: T7-L1
Action: compresses and supports visceral
orgin, insertion, innervation, and action of the Rectus abdominis muscle
Paired muscle of anterior abdominal wall that is wider at top then the bottom
-Tendinous intersections form part of rectus sheath at umbilical, xiphoid and midway levels
origin: pubic symphysis and pubic crest
insertion: xiphoid process and outer surface of 5-7 intercostal cartilages
innervations: ventral rami T7-T12
Action: flexes abdomen and compresses it
what is the Linea semilunaris?
what is the pyramidis muscle?
Linea semilunaris is the lateral border of the rectus abdominus muscle
Pyramidis muscle is a small muscle that appears at the pubic tubercle that connects to the linea alba at very low below the umbilicus
-missing in about 20 percent of people
What is the Rectus sheath and what occurs at the arcuate line?
- Made of fascia and aponeurosis of muscle that encompasses the Rectus abdominis m.
- External oblique tendon will lay always lay anterior
- Internal oblique will split laying its tendon both anterior and posterior of the RA muscle for upper 3/4s, but after the arcutate line will transition to just sit anteriorly
- Transverse abdominis tendon will sit posterior to the RA until the arcuate line and will transition to sit anterior to RA
- Therefore below the arcuate line the RA muscle will sit on top the transversalis fascia
where does the Thoraco-abdominal nerves run?
T7-T11
-They are a continuation of the intercostal nerves and contain both motor and sensory information
-Run between the Transverse abdominis muscle and the internal oblique muscle
where does the subcostal nerve run?
T12
-runs along the interior 12th rib; motor and has a sensory that is superior to the iliac crest
