ABDOMEN WALL ANATOMY

Question 1

 What are the layers traversed

 Laterally?

Answer 1

 Skin
 Subcutaneous tissue
 Camper fascia (superficial fatty layer)
 Scarpa fascia (deep membranous layer)
 Superficial layer of investing fascia (covers the muscle)
 External oblique – inferomedial
 Intermediate layer of investing fascia (covers the muscle)
 Internal oblique – superomedial
 Deep layer of investing fascia (covers the muscle)
 Transverse abdominus muscle
 Transversalis fascia (aka endoabdominal fascia)
 Intraperitoneal fat
 Parietal peritoneum

Question 2

 What are the layers traversed

 medially?

Answer 2

 Skin
 Subcutaneous tissue
 Rectus sheath
-Superior to umbilicus: rectus abdominis is in between 2 layers of aponeurosis of internal oblique)
-Inferior to umbilicus: rectus abdominis is below rectus sheath

 Rectus abdominis
 Transversalis fascia
 Extraperitoneal fat
 Peritoneum

Question 3

 Rectus sheath

Answer 3

made of the aponeurosis of external oblique muscle, aponeurosis of internal oblique muscle and aponeurosis of transversus abdominis.

also encloses superior n inferior epigastric vessels

Question 4

 Rectus sheath

Answer 4

made of the aponeurosis of external oblique muscle, aponeurosis of internal oblique muscle and aponeurosis of transversus abdominis.

Question 5

external oblique way

Answer 5

inferomedial

Question 6

internal oblique way

Answer 6

superomedial/ inferolateral

Question 7

transversus abdominis way

Answer 7

transversely

Question 8

neurovasculature runs bw

Answer 8

internal oblique and transversus abdominus

Question 9

arcuate line

Answer 9

halfway bw umbilicus and pubic symphysis

Question 10

vascular supply of anterolateral wall

superiorly

Answer 10

superior epigastric artery
musculophrenic artery
(both of these are terminal arteries to the internal thoracic artery)

Question 11

vascular supply of anterolateral wall

laterally

Answer 11

branches of 10th, 11th intercostal arteries n subcostal artery

Question 12

vascular supply of anterolateral wall

laterally

Answer 12

branches of 10th, 11th intercostal arteries

subcostaal artery

Question 13

vascular supply of anterolateral wall

inferiorly

Answer 13

inferior epigastric artery (branch of external iliac artery)-medially/centre of abdo is

deep circumflex iliac artery- laterally - like near hips is

Question 14

venous drainage

Answer 14

Thoracoepigastric vein – flow between superficial epigastric vein (tributary of femoral vein) and lateral thoracic vein (tributary of the axillary vein)

Question 15

internal thoracic artery

Answer 15

internal thoracic runs parasternally. if u see sternal and 2 circles next to it, its that.

Question 16

Skin, muscles, parietal peritoneum and anterolateral abdominal wall supplied by
the __ spinal nerves.

Answer 16

T7-L1

Question 17

nerves of abdo wall

Answer 17

T7-T11 (intercostal/thoracoabdominal nerves)-goes bw internal oblique and transversus abdominis muscles; enter the rectus sheath

T12 (subcostal nerve)

Iliohypogastric nerve (L1)

Ilioninguinal nerve (L1) – passes through the inguinal canal (further down than iliohypogastric)

Question 18

Dermatomes

Answer 18

Nerves T7-T9 supply the skin from the xiphoid process to just above the
umbilicus.
! T10 supplies the umbilicus.
! Nerves T11-L1 supply skin from below the umbilicus to the pubic region.

Question 19

superficial lymphatic vessels:

above the transumbilical plane

Answer 19

axillary lymph nodes

Question 20

superficial lymphatic vessels:

Below transumbilical plane

Answer 20

superficial inguinal lymph nodes

Question 21

hesselbach’s triangle

Answer 21

• laterally by the inferior epigastric artery;
• medially by the rectus abdominis muscle; and
• inferiorly by the inguinal ligament

Question 22

inguinal ligmaent is from aponeurosis of which muscle

Answer 22

external oblique

Question 23

inguinal canal contents

Answer 23

• In men,spermatic cord
• In women, Round ligament of the uterus
• In both sexes, Ilio-inguinal nerve
and other stuff

Question 24

boundaries of inguinal canal

roof

Answer 24

falx inguinalis

Arching fibres of the internal oblique and transversus abdominis

Question 25

boundaries of inguinal canal | ANTERIOR:

Answer 25

External oblique aponuerosis, | internal oblique muscle (laterally

Question 26

boundaries of inguinal canal | FLOOR

Answer 26

``` inguinal ligament lacunar ligament (medially) ```

Question 27

boundaries of inguinal canal | POSTERIOR

Answer 27

``` transversalis fascia conjoint tendon (medially) ```

Question 28

deep inguinal ring is ___ to inferior epigastric artery

Answer 28

lateral

Question 29

cremaster muscle

Answer 29

* Contracts: lifts testis up to save heat –wen its cold * Relaxes to lower testists wen its hot * Innervated by genital branch of genitofemoral nerve

Question 30

dartos muscle

Answer 30

wrinkles skin of scrotum

Question 31

spermatic cord covering

Answer 31

external spermatic fascia-external oblique cremasteric fascia-internal oblique internal speramtic fascia- transversalis fascia

Question 32

scrotum layers

Answer 32

``` skin superficial fascia (with dartos muscle) external spermatic fascia cremasteric muscle n fascia internal spermatic fascia arealar tissue tunica vaginalis ```

Question 33

contents of scrotum

Answer 33

vessels: testicular artery, cremasteric artery, artery to vas, pampiniform plexus of veins nerves: genital branch of genitofemoral nerve other: ductus deferens, processus vaginalis, lymphatics

Question 34

penis n scrotum drain to

Answer 34

superficial inguinal lymph nodes

Question 35

testis drain into

Answer 35

right n left lumbar (caval/aortic) lymph nodes

Question 36

septum of scrotum

Answer 36

continuation of darts fascia, divide scrotum to right n left part

Question 37

nerve supply of scrotum

Answer 37

anterior surface: anterior scrotal nerves off illioinguinal nerve (L1) posterior surface- posterior scrotal nerves off the perineal branch of the pudendal nerve (S2-S4)

Question 38

which testes hangs lower?

Answer 38

left. left drains into left renal vein (smaller than ivc) right drains into IVC difference in speed of venous blood drainage causes this difference

Question 39

which testes hangs lower?

Answer 39

left. left drains into left renal vein (smaller than ivc) right drains into IVC difference in speed of venous blood drainage causes this difference - left hangs more- higher pressure

Question 40

vascular supply of testes

Answer 40

testicular arteries | & pampiniform venous pelxus

Question 41

innervation of scrotum

Answer 41

* Anterior 2/3 by ilioinguinal nerve | * Posterior 1/3 by pudendal nerve

Question 42

innervation of testis

Answer 42

* Sympathetic + pelvic autonomic fibres * Sensory fibres T10-11 * NO parasym supply

Question 43

transpyloric plane

Answer 43

- Fundus of GB - Neck of the pancreas - Pylorus of the stomach - Duodenum (first part) - Crosses hila of kidneys - Duodenal-jejunal flexure - Colic flexure (splenic + hepatic) - Origin of SMA from aorta - Termination of SMV into HPV - Conus medullaris - Cysterna chyli - Root of transverse mesocolon

Question 44

transpyloric plane

Answer 44

L1/L2 disc | aka 9th costal cartilage

Question 45

transpyloric plane

Answer 45

L1/L2 disc aka 9th costal cartilage located halfway between the umbilicus and xiphisternum (or halfway between the sternal notch and pubic symphysis).