Anterior Abdominal Wall & Inguinal Region Flashcards Preview

Anatomy (Karen) > Anterior Abdominal Wall & Inguinal Region > Flashcards

Flashcards in Anterior Abdominal Wall & Inguinal Region Deck (31):

What direction are the fibres of the external oblique?

anteroinferior (follow external intercostals)


What is the origin of the external obliques?

anterior surface of the lower 8 ribs

edge to edge with pec major and serratus anterior


What is the insertion of the external obliques?

medially: linea alba/vertical raphae

posteriorly: free

inferiorly: anterior half of the iliac crest, ASIS, pubic tubercle, and pubic crest


What are the 3 free edges of the external oblique?

superior aponeurotic edge (origin of pec +)

free posterior edge

inferior edge between the ASIS and the pubic tubercle (inguinal ligament)

*triangular opening between pubic tubercle and pubic crest*


What is the orientation of the internal oblique fibres?

back pockets/ posteroinferior

(follow internal intercostals)


What is the origin of the internal oblique?

thoracolumbar fascia (posterior)

anterior 2/3rds iliac crest/lateral 2/3rds of inguinal ligament (free edge of external oblique)


What is the insertion of the internal oblique?

costal margin

linea alba

conjoin tendon to pubic crest w/transversus abdominus


What is the origin of transversus abdominus?

deep surface of costal margin (continuous with diaphragm)

thoracolumbar fascia

anterior 2/3rds of iliac crest

lateral 1/2 of inguinal ligament


What is the insertion of transversus abdominus?

linea alba

conjoin tendon to pubic crest w/internal oblique


What is the origin of rectus abdominus?

body & crest of pubis


What is the insertion of rectus abdominus?

anterior surface of costal cartilages 5, 6, & 7


What is the arcuate line?

end of posterior rectus sheath, ~2.5cm below the umbilicus


What is the innervation of the anterior abdominal wall?

ventral rami of T7- L1:

T7-T9 above umbilicus

T10 umbilicus

T11-12 below umbilicus

L1 groin



What is the arterial supply of the anterior abdominal wall?

superior epigastric (internal thoracic)

anastamoses with

inferior epigastric (external iliac)

in the posterior recuts sheath

*superficial epigastric lies in superficial fascia*


Venous drainage of the anterior abdominal wall is by

superficial and deep veins accompanying arteries

drain into portal or caval circulation


What is the lacunar ligament?

medial reflection of the inguinal ligament (before attachment at the pubic tubercle) to the pectineal line


What is the pectineal ligament?

runs on pectineal line of the pubic bone

extension of the lacunar ligament


Gonads develop

in the extraperiotneal fat of the superor lumbar region of the posterior abdominal wall


What is the deep inguinal ring?

opening in the transversalis fascia (passage of testis)

halfway between the ASIS & the pubic tubercle

fingers breadth above the inguinal ligament


What is the superficial/external inguinal ring?

triangular opening in external oblique in its attachment between the pubic tubercle and pubic crest

(passage of testis & spermatic cord)


What forms the floor of the inguinal canal?

inguinal ligament


What forms the roof of the inguinal canal?

arching fibres of internal oblique & transversus abdominus


What forms the anterior wall of the inguinal canal?

external oblique aponeurosis, lateral internal oblique


What forms the posterior wall of the inguinal canal?

transversalis fascia, conjoint tendon (medially)


Internal spermatic fascia is acquired

as the spermatic cord passes through the transversalis fascia


Cremasteric fascia & muscle is acquired from

passage of the spermatic chord through transversalis abdominus and internal oblique


External spermatic fascia is acquired

as the spermatic cord exits the external inguinal ring through external oblique


What is an indirect inguinal hernia?

  • most common
  • passes through inguinal canal via the deep ring into the scrotum via the superficial ring
  • arises from incomplete closure of the processus vaginalis


What is a direct inguinal hernia?

  • protrusion forward in the region of the inguinal canal through a weakness in its posterior wall
    • not entering the canal via the deep ring, but rather protruding into it


What predisposes to inguinal hernias?

  • severing the L1 fibres innervating the conjoin tendon in appendectomy
    • weakens ability of internal oblique to close the inguinal canal on increased intra-abdominal pressure


What prevents chronic inguinal hernia on raised intra-abdominal pressure?

closure of the inguinal canal by contraction of internal and external oblique muscle fibres that comprise the roof