abdomen Flashcards
subcostal plane: location
inferior border of 10th costal cartilage
transtubercular plane: location
passes through iliac tubercles, body of L5
transumbilical plane: location
passes through umbilicus, IV discs between L3-L4
abdomen layers: superficial to deep
- skin
- camper fascia, scarpa fascia (subcutaneous)
- muscles: external oblique, internal oblique, transversus abdominis (with investing fascia in between)
- endoabdominal (transversalis) fascia
- extraperitoneal fat
- parietal peritoneum
linea alba: formation
aponeuroses interweave
arcuate line: distance
1/3 of the way from umbilicus to pubic crest
rectus sheath: formation
formed by aponeuroses of all 3 flat muscles
arcuate line: significance
- inferior to arcuate line, the aponeuroses of all 3 flat muscles pass anterior to rectus abdominis
- only transversalis fascia covers rectus abdominis posteriorly: potential site of weakness
median umbilical fold: location
- apex of bladder to umbilicus
- covers median umbilical ligament and remnant of urachus
medial umbilical folds: location
- cover medial umbilical ligaments, formed by occluded parts of umbilical arteries
lateral umbilical fold: location
- cover inferior epigastric vessels
lateral inguinal fossa: location, contents
- lateral to lateral umbilical folds
- contain deep inguinal rings (potential hernia site)
medial inguinal fossa: location, contents
- between medial and lateral folds
- forms inguinal triangle
supravesicular fossa: location, contents
- between median and medial folds, formed as peritoneum reflects from anterior abdominal wall onto bladder
inguinal ligament: formed by
free inferior border of external oblique aponeurosis
direct inguinal hernia: location
passes through/around inguinal canal, traversing medial third of canal. exits abdominal wall via superficial ring
indirect inguinal hernia: location
traverses inguinal canal (within processus vaginalis), entering deep inguinal ring and exiting superficial ring
inguinal region: location, function
- between anterior superior iliac spine, pubic tubercle
- where structures enter, exit abdominal cavity
inguinal canal: formation
formed in relation to relocation of gonads in fetal development
- fetal testes: pulled by gubernaculum, relocate from dorsal abdominal wall to deep inguinal rings
- fetal ovaries: relocate from dorsal abdominal wall to lesser pelvis, where gubernaculum attaches caudal pole of ovary
main structures of inguinal canal
spermatic cord: ductus deferens
vestigial round ligament of uterus
ilioinguinal nerve, blood vessels, lymphatics
inguinal canal: openings
deep ring: internal entrance, evagination of transversalis fascia
superficial ring: exit in external oblique aponeurosis
spermatic cord: fascia
- internal spermatic fascia: derived from transversalis fascia at deep inguinal ring
- cremasteric fascia: derived from internal oblique aponeurosis
- external spermatic fascia: derived from external oblique aponeurosis, its investing fascia
spermatic cord: blood supply to/from testes and epididymis
- testicular artery and veins: arise from aorta at L2
- pampiniform venous plexus: 12 veins that converge superiorly at testicular veins
spermatic cord: vas deferens
(same as ductus deferens) muscular tube that conveys sperm from epididymis to ejaculatory duct