Anterior Abdominal Wall and Inguinal Canal | B2 WK 4 Flashcards
What is the space between the thoracic & pelvic cavities?
Abdominal cavity
What is the superior border of the abdominal cavity
Thoracic diaphragm
What is the inferior border of the abdominal cavity
Pelvic inlet
What is the abdominal cavity lined by
parietal peritoneum
What are the bones of the abdomen?
Lumbar vertebrae
Os Coxa
What is the midclavicular plane?
Midpoint of the clavicles to the mid-inguinal point
What is the subcostal plane?
Across inferior border of 10th costal cartilage
What is the transtubercular plane?
Passes through iliac tubercles on each side and across the body of L5.
what are the 9 regions of the abdomen?
- RH - Right hypochondrium
- TL - right flank (lateral region)
- RI - right inguinal
- Epigastric
- Umbilical
- Pubic (or hypogastric)
- LH - left hypochondrium
- Left Flank (lateral region)
- LI - left inguinal
What are the two planes that make up the quadrants of the abdomen?
Median Plane (R/L halves of Body)
Transumbilical Plane (Passes thru umbilicus - btwn L3/L4)
What are the bony landmarks of the abdomen?
Iliac crest
Anterior Superior Iliac Spine (ASIS)
What are the muscular landmarks of the abdomen?
Ext. Abdominal Oblique
Rectus abdominis
What are the tendinous landmarks of the abdomen?
Linea alba
Semilunar line
inguinal ligament
Tendinous intersection
What is McBurney’s Point?
Superficial landmark for the appendix [RLQ]
Located ~2/3 between the umbilicus and ASIS
(Referred pain of Appendix felt here)
From SUPERFICIAL to DEEP - what are the layers of the Abdominal wall? [12 pts]
SUPERFICAL
1. Skin
2. Campers Fascia - Superficial SubQ
3. Scarpa Fascia
4. Investing (deep) Fascia
5. External Oblique
6. Investing fascia
7. Internal Oblique
8. Investing fascia
9. Transverse Abdominus
10. Endoabdominal fascia
11. Extraperitoneal fat
12. Parietal peritoneum
What condition is characterized by interruption of the urethra resulting in collection of urine in other cavities
Extravasation of Urine
What causes extravasation of Urine?
Urine/blood can get trapped in scrotum, penis, and the abdominal wall due to the relationship between perineal fascia and abdominal fascia
What are the 4 muscles of the anterolateral abdominal wall?
anterior: Rectus Abdominus
lateral: external oblique, internal oblique, & transversus abdominus
All 4 muscles of the anterolateral abdominal wall are innervated segmentally by:
ventral rami of T6-T12 & L1
What muscles work to compress and support abdominal viscera?
Rectus Abdominus
external oblique
internal oblique
transversus abdominus
What muscles rotate & flex the trunk?
External & internal oblique muscles
What muscle stabilizes & controls the tilt of the pelvis AND flexes the trunk?
Rectus abdominus
What are the 6 F’s of abdominal enlargement?
Food
Flatus
Fat
Fluid
Feces
Fetus
O, I, NS | External Oblique
O: Ribs 5-12
I: Linea alba
NS: T7-T12
Which way do muscle fibers run in ext. oblique?
Super-lateral (hands in pockets)
O, I, NS | Internal Oblique
O: Thoracolumbar fascia, iliac crest, inguinal lig
I: Inf. borders of ribs 10-12, linea alba, & pectineal line
NS: T6-T12, L1
Which way do muscle fibers run in int. oblique?
infero-lat to supero-medial
(clutching your pearls)
O, I, NS | Transversus Abdominus
O: 7th-12th Costal cartilages, thoracolumbar fascia, iliac crest, & inguinal ligament
I: Linea alba, pubic crest, & pectineal line via conjoint tendon
NS: T6-T12, L1
Describe ipsilateral contraction of the trunk
External & internal oblique muscles from the SAME side
Lateral trunk flexion - bend towards contracted side
Describe contralateral contraction
External oblique from one side and internal oblique from the opposite side
Trunk torsion
In trunk torsion, the twist will be towards the side of the _______________________
Contracted int. oblique
O, I, NS | Rectus Abdominus
O: pubic symphsis & pubic crest
I: xiphoid process + 5-7th costal cart.
NS: T6-T12
What is the rectus sheath formed from?
aponeuroses of external oblique, internal oblique, & transversus abdominus
What would you find in the rectus sheath?
- Rectus abdominus (sup. 2/3)
- Sup/Inf epigastric A.V.
- Lymphatic Vessels
- Distal portions of thoracoabdominal nerves
What is the arcuate line?
Point where rectus abdominus travels within rectus sheath (deep)
Superficial veins of the abdominal wall radiate out from the….
umbilicus
If you are a blood cell in a vein traveling superior to the umbilicus, where are you drained into?
Axillary V. Via the lateral thoracic V.
If you are a blood cell in a vein traveling inferior to the umbilicus, where are you drained into?
Femoral V. via the superficial epigastric V.
The paraumbilical vv. connects what? why is it important?
Connects the network through the umbilicus and along the ligaemntum teres of the liver to the portal vein
*Forms an important portal-systemic venous anastomosis
What a. & v. supply the lateral wall of the abdomen?
(ext oblique, int oblique, transversus abdominus)
Intercostal & lumbar a./v.
What is the blood supply to the rectus abdominus?
Superior & Inferior epigastric
The epigastrics anastomosis in the abdomen. Where does the superficial arise from? inferior?
S: internal thoracic
I: external iliac
Lymphatic drainage moves __________ from the umbilicus
AWAY
Drainage above the umbilicus (lymph) drains to…
anterior axillary lymph nodes
Drainage below the umbilicus (lymph) drains to…
superficial inguinal lymph nodes
Why do the lymphatic drainage between the testes and scrotum differ?
Teste lymphatic drainage goes to the superficial inguinal lymph nodes. Lymphatic drainage from the testes goes to the lumbar lymph nodes. This is b/c the scrotum is an outpouching. The testes org. in the lumbar area and move down during development
(i.e., blame embryo)
Spinal levels ____ - ____ are the thoraco-abdominal nerves
T7-T11
thoraco-abdominal Motor innervation
Ext. Abd. Oblique
Int. Abd. Oblique
Transversus abdominis
Rectus abdominis
thoraco-abdominal Sensory innervation
T7-T9: Skin superior to umbilicus
T10: skin around the umbilicus
T11: skin inferior to umbilicus
Subcostal nerve is at spinal level…
T12
Subcostal nerve motor innervation
Ext. Abd. Oblique
Int. Abd. Oblique
Transversus abdominis
Rectus abdominis
Subcostal nerve sensory innervation
skin superior to iliac crest and inferior to umbilicus
iliohypogastric nerve is spinal level…
L1
iliohypogastric nerve motor innervation
Internal oblique, Transversus abdominus
iliohypogastric nerve sensory innervation
region of skin from iliac crest and superior to inguinal ligament
Ilioinguinal Nerve is spinal level…
L1
T/F: the Ilioinguinal Nerve travels through the deep inguinal ring
false - only the inguinal canal
Ilioinguinal Nerve motor innervation
Internal oblique
Transversus abdominus
Ilioinguinal Nerve Sensory innervation
Skin of lower inguinal region
Mons pubis
Anterior scrotum/labium majus
medial thigh
Genitofemoral nerve spinal level
L1-2
The genitofemoral nerve - genital branch (Sensory + motor innervation)
Sensory - innervation to the root of the penis, anterolateral surface of scrotum/mons pubis, & labia majora
Motor - innervation of cremaster
The genitofemoral nerve - femoral branch (Sensory + motor innervation)
Sensory innervation to small area of the skin on the medial aspect of the superior anterior thigh
What is the cremasteric reflex?
This is when the cremaster muscle contracts. It is caused when the skin on the medial aspect of the superior thigh is lightly poked or stroked.
Stroking of the inner thigh in the cremasteric reflex stimulates sensory fibers of the __________ nerve. This then activated the motor fibers of the ___________ branch of the ____________ nerve yielding contraction.
- ilioinguinal N
- genital branch
- genitofemoral n
