Abdominal Wall & Peritoneum Flashcards
(25 cards)
** ALWAYS QUESTION IN TEST ABOUT THIS:
Quadrants and Planes of the abdomen
Quadrants:
Right Upper
Left Upper
Right Lower
Left lower
Planes:
Right hypochondrium
Epigastric
Left hypochondrium
Right flank
Umbilical
Left Flank
Right Groin
Pubic
Left Groin
Layers of the Abdominal Wall
From outer to inner
- Skin
- Superifical fascia (Campers and Scarpas)
- external oblique
- Internal Oblique
-Transversus Abdominis
-Transversalis Fascia
-Extraperitoneal fascia
Parietal Peritoneum
- layers and then superifical fascia
Muscles of the Abdominal Wall - label diagram
Practical test hint: Know the Fibre Direction and Layers
Lecture Slide
Muscles of the Abdominal Wall:
Rectus Abdominis
Origin, Insertion, action, nerve
Origin: Pubic Tubercle, Crest &
Symphysis
Insertion: Costal cartilages ribs 5‐7 & xiphoid process
Action:
Flex trunk
Support/compress abdominal wall
Nerve: Anterior rami of thoracic spinal nerves
External oblique
Origin, Insertion, action, nerve, fibre direction
Origin: Ribs 5‐12
Insertion: Iliac Crest & Linea Alba via aponeurosis
(below pec. minor)
Aponeurosis: From Xiphoid process to the pubic symphysis (Lower boarder forms inguinal ligament)
Action:
* Flex trunk (both)
* Turn to opposite side/bend trunk to same side (single)
Nerve: Anterior rami of thoracic
spinal nerves
Infero‐medial (Hands in pockets)
Internal oblique
Origin, Insertion, action, nerve, fibre direction
Origin: Thoracolumbar fascia,
Inguinal Lig. & Iliac Crest
Insertion: Ribs 9‐12, Linea Alba & Pubis (via Conjoint Tendon)
Action:
* Flex trunk (both)
* Bend & turn trunk to
same side (single)
Nerve: Anterior rami of thoracic
spinal nerves (Some L1)
Fibre direction: Supero‐medial
Transverse abdominis
Origin, Insertion, action, nerve, fibre direction
Origin
* Thoracolumbar fascia
* Iliac Crest
* Inguinal Lig.
* Costal Cartilage Rib 7‐12
Insertion:
Linea alba
Pubic crest (via conjoint tendon)
Pectineal line
Action:
Support abdominal wall
Nerve: Anterior rami of thoracic spinal nerves (Some L1)
Fibre direction: Transverse
Muscles of the Abdominal Wall
Label cross section
Lecture Slide
Label XRAY of abdominal muscles
Lecture Slide
Rectus Sheath:
Where is it?
Upper 3/4:
All 3 Abdominal wall muscles
surround Rectus Abdominis
Lower 1/4 (Below the
Arcuate Line):
Rectus sheath over front of
Rectus Abdominis only
Behind = Tranversalis fascia &
Parietal Peritoneum
The Rectus Sheath – Arcuate Line
- where is it
(Roughly half way along line
from umbilicus to pubic
bones)
Arterial Supply
Superior Epigastric
* From Internal Thoracic (runs down chest, pierces diaphragm)
Inferior Epigastric
-much larger and greater blood supply
(From External Iliac)
Both arteries run underneath Rectus Abdominis (on top of transversalis fascia
and within the rectus sheath) and anastamose together
Superifical Nerves & Venous Drainage
- What are they and where are they
Lecture Slide
lateral cutaneous
branches 7-12
intercostal nerves
anterior cutaneous
branches of 7-12
intercostal nerves
Iliohypogastric n. (L1)
VEINS:
1. Axillary vein
2. Thoracoepigastric vein
3. Superifical epigastric vein
4. Femoral vein
Thoracic Spinal nerves
-what/where are they on diagram
- what is the neurovascular plane
Anterior cutaneous branch
Lateral cutaneous branch
anterior ramus
Spinal nerve
Posterior ramus
neurovascular plane
- between internal oblique and transversus abdominis
Key dermatone locations in abdominal region
Skin, Muscle & Parietal Peritoneum = supplied
by T7‐12 (intercostal) & L1
(Iliohypogastric/Ilioinguinal) spinal nerves
All of these nerves = Anterior rami
Neurovascular plane: These nerves run
between Transversus abdominis and Internal
Oblique (analogous to the intercostal
neurovascular plane) before piercing the
muscular wall to reach the skin
Umbilical = T10
Lymphatic drainage
superficial lymphatics follow veins = Upper 1/2 to axillary nodes
Lower 1/2 to superior inguinal nodes
Peritoneum types and what do they cover
- Visceral – Covers abdominal
viscera (organs) - Parietal – Lines body wall
- Visceral peritoneum
comes back around on
itself to form a MESENTERY anchoring the viscera to the posterior body wall
**Small amount of serous fluid between
– reduces friction of movement
Both layers are continuous with each other
Peritoneum - Sensation
- for each Peritoneum type
Parietal:
* Sensitive to pain, touch, temperature & pressure
* Nervous supply by:
- Somatic nerves to body wall (Thoracic and Lumbar nerves)
- Phrenic nerve (up by diaphragm)
-Obturator nerve (down in pelvis)
Visceral/Mesenteries
- Sensitive to stretch – Autonomic Nervous System (ANS) ‐ afferent fibres
E.g. Stretching/distension (Think about when you eat too much…)
Peritoneum ‐ Mesenteries
- Types at GI tract, midgut, hindgut and foregut
- GI Tract = Suspended by Mesenteries
- Midgut & Hindgut = suspended only by
one mesentery (dorsal) - Foregut however = suspended by both
a VENTRAL and a DORSAL mesentery - (Becomes important for
understanding embryology of the
gut and the various ligaments of
the foregut)
Intraperitoneal Vs RetroPeritoneal
and examples
INTRA‐peritoneal
* Completely contained in visceral peritoneum & suspended by a mesentery
* (E.g. Stomach, Liver, Gall bladder, Spleen, Proximal Duodenum, Small Intestine, Appendix, Transverse Colon,
Sigmoid Colon)
RETRO‐peritoneal
* Lays between peritoneum and body wall
– Partial cover of peritoneum
(E.g. Kidneys, Pancreas, Distal
Duodenum, Ascending & Descending Colon, Upper 2/3 of Rectum)
Some parts of the gut are
suspended by Mesenteries
whilst other parts are not…
What parts are
Intraperitoneal and what parts are Retroperitoneal
Intraperitoneal
- Small bowel from Jejunum to terminal Ileum ‐ Mesentery
- Transverse colon: Transverse mesocolon
-Sigmoid colon: Sigmoid mesocolon
Retroperitoneal
- Distal duodenum
- Ascending and descending colon
-Rectum
Greater Sac & Lesser Sac
- where is it/what does it have
Greater Sac = Peritoneal Cavity Proper
(Basically everything that is
not the lesser sac)
Lesser Sac = behind lesser
omentum and stomach
Omental/Epiploic Foramen
- bounded by?
-
Bounded anteriorly
by free edge of lesser omentum (containing portal
triad)
Bounded posteriorly by IVC
Label the cross section
Lecture Slide
