abdominal wall and Inguinal region Flashcards
nine regions of abdominal cavity
right hypochondriac, epigastric, left hypochondriac right lateral (lumbar), umbilical, left lateral (lumbar) right inguinal (groin), pubic (hypogastric), left inguinal
abdominal cavity is
enclosed anterolaterally by dynamic musculo-aponeurotic abdominal walls
separated superiorly from thoracic cavity and posteriorly from the posterior thoracic vertebrae by the diaphragm
under cover of the thoracic cage superiorly extending to the 4th intercostal space
continuous with pelvic cavity
planes that divide to 9 regions
horizontal: subcostal plane (through inferior border of 10th cosal cartilage on each side) and transtubercular plane (passing through the iliac tubercles and the body of L5)
vertical: 2 midclavicular planes: passing from midpoint of clavicles to midinguinal points
midinguinal point
midpoint of lines joining anterior superior iliac spines and superior edge of pubic symphysis
planes that define 4 quadrants
transumbilical: through umbilicus and L3/L4 IV disc
median plane: longitudinally through body
median umbilical fold
extending from apex of urinary bladder to umbilicus
covers median umbilical ligament
median umbilical ligament
remnant of urachus that joined apex of fetal bladder to umbilicus
two medial umbilical folds
lateral to median umblical fold
cover medial umbilical ligaments
medial umbilical ligaments
formed by occluded parts of umbilical arteries
two lateral umbilical folds
lateral to medial umbilical folds
cover inferior epigastric vessels
peritoneal fossae
depressions lateral to umbilical folds
location of hernias, determines classification
supravesical fossa
between median and medial umbilical folds
formed as peritoneum reflects from anterior abdominal wall onto the bladder
level rises and falls with filling and emptying of bladder
medial inguinal fossae
between the medial and lateral umbilical folds, areas also commonly called inguinal triangles (Hesselbach triangles)
potential sites for direct inguinal hernias
lateral inguinal fossae
lateral to lateral umbilical folds
include deep inguinal rings and are potential sites for most common type of inguinal hernia: indirect inguinal hernia
incisional hernia
protrusion of omentum (fold of peritoneum) or an organ through a surgical incision or scar
causes of protuberance of abdomen
food, fluid, fat, feces, flatus and fetus
musculophrenic artery
originates off internal thoracic artery
descends along costal margin
distributed along abdominal wall of hypochondriac region, anterolateral, diaphragm
superior epigastric artery
originates off of internal thoracic artery
descends in rectus sheath deep to rectus abdominis
distributed along superior rectus abdominis and superior part of anterolateral abdominal wall
inferior epigastric artery
originates off external iliac artery
runs superiorly and enters rectus sheath
runs deep to rectus abdominis
distributed along inferior rectus abdominis and medial part of anterolateral abdominal wall
drainage of abdominal lymphatic vessels
superior to umbilicus: drain to axillary lymph nodes
inferior: drain to superficial inguinal lymph nodes
inguinal region
extends between anterior superior iliac spine and pubic tubercle
inguinal hernia commonality
86% in males because of passage of spermatic cord through inguinal canal
inguinal ligament
most inferior part of external oblique aponeurosis
iliopubic tract
thickened inferior margin of transversalis fascia
runs parallel and deep (posterior) to inguinal ligament
reinforces posteror wall and floor of inguinal canal as it bridges structures (Hip flexors and neurovascular supply of LL) traversing the retro-inguinal space
lacunar ligament
fibers from inguinal ligament that attach to superior ramus of pubis, lateral to pubic tubercle
fibers continue to run along pectin pubis as pectineal ligament of Cooper
reflected inguinal ligament
fibers of inguinal ligament arch superiorly to blend with contralateral external oblique aponeurosis
inguinal canal
formed in relation to relocation of gonad during fetal development
about 4 cm long in adults
inferomedially directed oblique passage between superficial and deep inguinal rings
lies parallel and just superior to medial half of inguinal ligament
main structures of inguinal canal
spermatic cord: conveying ductus deferens in males and vestigial round ligament of uterus in females
also contains blood and lymphatic vessels and ilio-inguinal nerve
openings of inguinal canal
deep (internal) ring: internal entrance to canal, evagination of transversalis fascia superior to middle of inguinal ligament and lateral to inferior epigastric vessels
superficial (extenal) inguinal ring: exit: slit like opening in aponeurosis of external oblique, superolateral to pubic tubercle. lateral and medial crura are lateral and medial margins. intercrural fibers form superolateral margin of ring
boundaries of inguinal canal
anterior wall: external oblique aponeurosis. lateral part reinforced by internal oblique
posterior wall: transversalis fascia: medial part reinforced by merging of pubic attachments of internal oblique and transversus abdominis aponeuroses into common tendon: inguinal falx (conjoint tendon)
roof: laterally by transversalis fascia, centrally by musculo-aponeurotic arches of internal oblique and transversus abdominis muscles and medially by medial crus and intercrural fibers
floor: laterally by iliopubic tract, centrally by superior surface of inguinal ligament and medially by lacunar ligament
fascial coverings of spermatic cord
internal spermatic fascia: derived from transversalis fascia at deep inguinal ring
cremasteric fascia: derived from fascia of both superficial and deep surfaces of internal oblique muscle
external spermatic fascia: derived from external oblique aponeurosis and its investing fascia
passof spermatic cord
begins at deep inguinal ring lateral to inferior epigastric vessels, passes through the nguinal canal, exits at the superficial inguinal ring and ends in the scrotum at the tests
cremaster muscle
loops in cremasteric fascia
extends as a continuation of internal oblique muscle
contraction draws testis superiorly in scrotum,when it is cold
dartos muscle
smooth muscle of fat free subcutaneous tissue of scrotum (dartos fascia) which inserts into the skin
darts assists in testicular elevation as it produces contraction of skin of scrotum
innervation of cremaster
genitalbranch of genitofemoral nerve L1, L2
derivative of lumbar plexus
innervation of dartos
autonoic
constituents of spermatic cord
ductus deferens, testicular artery, artery of ductus deferens, cremasteric artery, pampiniform venous plexus, sympathetic nerve fibers, genital branch of genitofemoral nerve, lymphatic vessels, vestige f processus vaginalis
ductus deferens
aka vas deferens
muscular tube that conveys sperms from epididymis to ejaculatory duct
courses through substance of prostate to open into prostatic part of urethra
testicular artery
arises from aorta (vertebral level L2) and supplies testis and epididymis
artery of ductus deferens
arises from inferior vesical artery
cremasteric artery
arises from inferior epigastric artery
pampiniform venous plexus
network formed by up to 12 veins that converge superiorly as the right or left testicular veins
vestige of processus vaginalis
may be seen as a fibrous thread in anterior part of spermatic cord extending between abdominal peritoneum and tunica vaginalis but also may not be detectable
