Anterior Abdominal Wall (Ach) - W1 Flashcards
Camper’s fascia
- outer, fatty layer
- continuous with superficial fascia of thorax, thigh, and perinem
- continues into external genitalia
Scarpa’s fascia
- deep, fibrous, membranous
- Fuses with superifical layer of scrotum to form dartos layer
- forms colle’s fascia in the perineum - attaches to urogenital diaphgram.
- attaches to deep fascia of the thigh.
Where do the apopneurosis of the 3 sets of muscle fibers intersect?
linea alba
What is the semilunar line
The location where the external oblique becomes tendinous.
3 flat muscles of abdominal wall:
- external oblique - superolateral to inferomedial fibers
- internal oblique - inferolateral to superomedial fibers
- transversus abdominis - mostly transverse fibers
What forms the fibrous arch of the conjoint tendon?
- internal oblique and transverus abdominis fusion
Pair of strap muscles on the anterior surface that extend from the xiphoid process and adjacent costal cartilages to pubic crest.
- rectus abdominis
Describe the divisions of the arcuate line of the rectus sheath:
- above line: anterior layer is formed by aponeurosis of external and internal obliques
- Below line: anterior layer consists of all 3 aponeuroses
Describe the transversalis fascia
- lines entire abdominopelvic cavity - below arcuate line
- forms posteiror layer of rectus sheath
3 folds on the inernal surface of anterolateral bdominal wall - inferior to umbilicus:
- median umbilical fold - covers remannt of urachus
- mediAL umbilicial fold - covers umbilical arteries
- lateral umbilical folds - cover inferior epigastric vessels
What are the nerves of the abdominal wall that are motor to muscles, and sensory to skin and periotneum?
- Intercostal nerve (T7-T11)
- Subcostal nerve (T12)
- Ilioinguinal and iliohypogastric nerves (branches of L1)
run between internal oblique and transversalis fascia.
Describe the arteries of the abdomen and where they come from.
-
Superior epigastric artery: descends behind rectus abdominus
- comes off internal thoracic
-
Inferior epigastric artery: ascends
- comes off external iliac
- lower 2 intercostal arties
- 4 lumbar arteries
- veins correspond to arteries
- there are extensive anastomses
Cause and common population affected by umbilical hernias
- common in newborns - weak anterior wall
- result form increased intra-abdominal pressure in presence of incompletel closure of anterior abdominal wall after ligation of umbilical cord after birth
-
Acquired - can form in women and obese. May result from trauma, surgery.
- FAT protrudes
Common population, assocation, and location for epigastric hernias
- common with obesity
- occurs above belly button
- protrusion through linea alba
Risk factor and location for spigelian hernias
- hernia of the semilunar line
- common in obese individuals
Where does the inguinal ligament extend from and where is it found?
- ASIS to pubic tubercle
- found at lower border of external oblique aponeurosis
What forms the inguinal canal
- processus vaginalis and testes during development
Explain the descent of the tests
- route follows gubernaculum testes
- pouch of peritoneum that pushes through the deep inguinal ring - aka processus vaginalis
- gonads descend retoperitoneally in 7th-8th month
- it is not an active process - just related to growth
What does the female inguinal canal contain? What is the equivalent of the gubernaculum?
- contains the ilioinguinal nerve
- round ligament of uterus –> terminates as labia majora
What is found in the inguinal canal?
- ilioinguinal nerve of L1
- spermatic cord (male)
- round ligament of uterus (female)
Describe the boundaries of the inguinal canal
- Anterior = aponeurosis of external oblique
- Posterior = fascia transversalis laterally, conjoint tendon medially
- Floor = rolled under edge of external oblique aponeurosis
- Roof = low fibers of conjoint tendon
What are the components of the spermatic cord?
- ductus deferens
- testicular artery
- testicular vein
- lymph vessels
- remants of processus vaginalis
- genital branch of genitofemoral nerve (supplies cremaster)
- ANS fibers
What does the fascia transversalis form in the spermatic cord?
internal spermatic fascia
What does the internal oblique become in the spermatic cord
cremaster muscle and fascia
What does the external oblqiue muscle become in the spermatic cord?
External spermatic fascia
Indirect hernia
- occurs in male children frequently
- hernia follows route of testicular descent - may have patent processus vaginalis
- same coverings as spermatic cord
- exits cavity lateral to inferior epigastric vessels (in deep inguinal ring)
Congenital indirect hernia
- bowel herniates into patent processus vaginalis
- bowel herniates through deep inguinal ring, inguinal canal and superficial ring
Direct hernia
- bulges through posterior abdominal wall in region of conjoint tendon
- occurs medial to epigastric vessels
- more common in elderly males w/weak abdominal muscles
Femoral hernia
- more common in females - wider pelvis
- found lateral to pubic tubercle
- inferior to inguinal ligament
Describe the borders of the rectus shealth:
- anterior = pt of attachment (tendinous intersections)
- lower posterior = arcuate line
- above arcuate = IO and EO
- below arcuate line = all 3 aponeuroses in front
