Inguinal Canal Flashcards
Key pelvic ligaments
Inguinal: ASIS to pubic tubercle, EO aponeurosis
Lacunar: connects inguinal and pectineal
Pectineal: runs on pectineal line
What is the inguinal canal. where does it extend and what does it carry?
Oblique passage through lower part of abdominal wall, to prevent herniation of abdominal contents
From deep to superficial inguinal rings
Males: things to and from testes (spermatic cord) + ilioinguinal nerve
Females: round ligament of uterus to labia majora
What is the superficial inguinal ring?
A triangular defect in aponeurosis of EO
Is superior and lateral to the pubic tubercle
Either side are medial and lateral crura, and give rise to external spermatic fascia
What is the deep inguinal ring?
Oval opening in transversalis fascia
is halfway between ASIS and Pubic symphysis (mid inguinal point), LATERAL to inferior epigastric artery
gives rise to internal spermatic fascia (or round lig. fascia)
How do the transversus abdominis and IO contribute to the inguinal canal?
What is the joining?
Transversus abdominis: does not contribute, only boundaries
IO: gives rise to Cremasteric muscle of spermatic cord
The conjoint tendon, where the two muscles here join medially on the pubic crest
What are the inguinal canal borders?
review sebs diagrams, page 58. Although think I kinda get it, learn the boundaries here
Anterior: aponeurosis of EO and IO of lateral third
Floor: Inguinal lig + lacunar ligament
Roof: fibres of IO and TA
Posterior: transversalis fascia + conjoint tendon
What is Hesselbach’s triangle?
site of direct hernia, where things can push through a weakened abdominal wall due to a weak anterior wall
Made up of lat border of rectus abdominis, the inferior epigastric artery (more lateral) and inguinal lig ( floor)
What is the spermatic cord?
collection of structures that passes from deep inguinal ring to testis, with 3 concentric layers of fascia.
How does the spermatic cord arise and what are the layers?
From a peritoneal diverticulum called the processus vaginalis. The outpouch remnant is the tuinca vaginalis
layers are the transversalis fascia (DIR)- internal spermatic fascia
IO: cremaster muscle
EO (SIR)- external spermatic fascia
note is continuous with scrotum
What are the spermatic cord contents?
3 arteries: gonadal (testicular/ ovarian); artery of vas deferens; cremasteric
3 nerves: genital branch of geniotfemoral; symp. from testicular plexus and ilioinguinal (not in the cord)
3 other: vas deferens; lymphatics, tunica vaginalis
1 vein: pampiniform plexus
How are the spermatic cord contents organised/
In the Int. spermatic fascia: testicular artery, vas deferens with its artery
Between ISF and cremaster: cremasteric artery
Between ESF and Cremaster: genital branch of GF nerve
outside: Ilioinguinal nerve
testicular artery artery of vas deferens pampiniform plexus (R ti IVC L to LRV) Genital branch of GF nerve LYMPHATICS
just remember ilio inguinal nerve does not run in canal , does not go through the DIR
- arises at AA at L2
- often cut during vasectomy
- help with temp regulation and form a single vein at the DIR
- supplies cremaster muscle and scrotal skin
- drain to para aortic nodes at L2
What is the cremasteric reflex?
Stroke superomedial thigh.
Stimulates femoral branch of genitofemoral and ilio inguinal (L1-2 roots) and stimulates genital branch, causing cremaster to contract
What are the types of hernias?
Indirect: Through entirety of inguinal canal, within ISF. typically congenital (will occur more in juveniles). Is lateral to epigastric artery.
Direct: through abdominal wall (hesselbachs), and is medial to inferior epigastric artery. males more likely.
femoral: inf. to IL through femoral canal. More females
Look for pubic tubercle (above and medial-inguinal, below and lateral- femoral)
Cough test, eg block mid inguinal point (DIR) then no bulge is indirect hernia.
