SIMPLIFIED MRCS ANATOMY-ABDOMEN AND PELVIS Flashcards
Enumerate layers of anterior abdominal wall (laterally)
Discuss attachment of external oblique muscle
+Origin—— costal
+Insertion—- lumbar , ilioinguinal , linea alba
+Innervation—- lower 6 thoracic and 1st lumbar(L1)
+Direction of fibres—- downward,forward and medially
Discuss internal oblique muscle
+Origin——lumbar fascia,ilioinguinal(iliac crest and inguinal ligament)
+Insertion—— costal(lower part makes conjoint tendon),linea alba
+Innervation—- lower 6 thoracic+ 1st lumbar(L1)
+Direction of fibres—— upward,forward and medially
Discuss transversus abdominis muscle
+Origin—— costal,lumbar,ilioinguinal
+Insertion—-Linear alba
+Innervation—-lower 6 thoracic+1st lumbar(L1)
+Direction of fibres —- Transverse
Discuss quadratus lumborum
+Origin—- lumbar fascia,iliac crest
+Insertion—-12th rib
+Innervation—— T12,L1-L3
+Action—- (1)Unilateral (alone): laterally flex the vertebral column
(2)Bilateral (together): depression of thoracic cage
Discuss rectus abdominis muscle
+Origin—- (1) At the level of arcuate line
Midway between umbilicus and symphysis pubis
(2) Above arcuate line
+Anterior—External oblique + Anterior lamina of internal oblique
+Posterior—Posterior lamina of internal oblique +Transversus abdominis muscle
+Insertion— Below arcuate line
+Anterior—All muscles
+Posterior—- Transversalis fascia
+Innervation— (1) lower 6 intercostal
(2) Nerve from lateral side
Discuss linea alba
+Definition—- bloodless midline
+Features— (1)Superiorly— wide
(2)Inferiorly—- narrow
(3)Bloodless
Define linea alba
Bloodless midline
What are the features of linea alba?
(1)Superiorly—- wide
(2)Inferiorly—-narrow
(3)Bloodless
What are the dimensions of linea alba?
(1)Superiorly—- wide
(2)Inferiorly—- narrow
Define linea semilunaris
Lateral border of rectus abdominis muscle
What is the blood supply of rectus abdominis muscle?
Superior and inferior epigastric arteries posterior to it
What is the location of superior and inferior epigastric arteries in the anterior abdominal?
Posterior to the rectus abdominis muscle
What is the blood supply to the anterior abdominal wall?
Superior and inferior epigastric arteries behind rectus abdominis muscle
What is the clinical significance of linea alba?
Midline incision through linea alba during exploration
What is the clinical significance of rectus abdominis muscle?
(1)During Pfannenstiel incision the muscle divided is the rectus abdominis
(2)Posteriorly,below arcuate line
+no posterior rectus sheath
+there is only Transversalis fascia behind the muscle
What is the clinical significance of linea semilunaris?
Spigelian hernia— (1)at the level of arcuate line
(2)at lateral border of rectus muscle (i.e., linea semilunaris
What is the location of spigelian hernia?
(1)at level of arcuate line
(2)At lateral border of rectus abdominis muscle(i.e., linea semilunaris)
What is the location of linea semilunaris?
At lateral border of rectus abdominis muscle
What is the origin of cremasteric fascia?
Internal oblique muscle
What is the origin of conjoint tendon?
Internal oblique muscle
What is the length of inguinal canal?
4cm
What is the location of superficial inguinal ring?
(1)At external oblique muscle
(2)Above pubic tubercle
What is the location of deep inguinal ring?
(1)At fascia transversalis
(2)1/2 inch above midpoint of inguinal ligament
(3)lateral to inferior epigastric vessels (site of indirect hernia)