Anatomy Flashcards
1
Q
Superior and Inferior attachments of EXT oblique
A
Overlaps the thoracic cage, edge to edge with pec major and serrates anterior
attaches onto anterior 1/2 of iliac crest, as far as ASIS, then jumps onto pubic tubercle and pubic crest
2
Q
What is the inguinal ligament?
A
Free inferior edge of External oblique between ASIS and pubic tubercle = Inguinal ligament
thickened and turns under itself
3
Q
Superior inguinal ring
A
triangular deficiency in External oblique/inguinal ligament, between pubic tubercle and pubic crest, through which the spermatic cord passes
4
Q
Superior and inferior attachments of INT oblique
A
Edge to edge with costal margins
Attaches onto anterior 1/2 of iliac spine as far as ASIS, then continues onto lateral 2/3 of inguinal ligament, then fibres arch up, over and down to insert into pubic crest, along with TA
5
Q
Superior and inferior attachments of Transversus abdomens
A
Underlaps costal margins (continuous w diaphragm)
Attaches onto anterior 1/2 of iliac crest as far as ASIS, then continues onto lateral 1/3-1/2 of inguinal ligament, then fibres arch up over and down to insert into pubic crest, along w IO
6
Q
Fibre arrangement of rectus abdominus
A
Diverging fibres (widen as they rise from inferior to superior) Long vertical fibres interrupted by horizontal tendinous intersections which create many short fibres and increase overall strength
7
Q
Where are RA tendinous intersections located?
A
Level of:
- Xiphisternum
- inbetween
- Umbilicus (T10)
8
Q
Attachments of Rectus abdominus
A
Inferior attachment to pubic crest, rises superiorly to insert into costal cartilages 5,6,7, edge to edge w pec major
9
Q
What is the rectus sheath composed of?
A
Above arcuate line/umbilicus:
Anterior sheath: EO aponeurosis and 1/2 of IO (splits 1/2 in front and 1/2 behind IO)
Posterior sheath: TA and 1/2 of IO
Contains vessels!
Below arcuate line:
posterior sheath cuts out; all aponeuroses pass IN FRONT OF RA to form anterior sheath
10
Q
Where is the neurovascular plane of the anterior abdominal wall?
A
Between TA and IO, in posterior rectus sheath
11
Q
What is the segmental innervation of the anterior abominal wall?
A
T7-9 above umbilicus
T10-12: between umbilicus and groin
12
Q
Arterial supply of anterior abdominal wall
A
Superior Epigastric: from above, branch of internal thoracic a
Inferior epigastric: from below, branch of external iliac a
13
Q
Venous drainage of anterior abdominal wall
A
Dual drainage
Portal and Systemic system
Portosystemic anastamoses: sites of overlap
14
Q
Lacunar ligament
A
crescentic extension from inguinal ligament onto pectineal line of the pubic bone
15
Q
Layers of the anterior abdominal wall
A
Skin Superficial fascia Ext oblique, int oblique, Transv abdominus (RA in midline) Deep fascia (fascia trasversali) Exztraperitoneal fat Peritoneum Abdominal cavity
16
Q
Where do the testes originate?
A
In extraperitoneal fat, high up on posterior abdominal wall
17
Q
What is the deep inguinal ring?
A
Deficiency in Transversalis fascia (deep fascia) that the spermatic cord passes through
Hole is 1/2 way between ASIS and tubercle, a fingers breadth above the inguinal ligament
18
Q
What is the floor of the inguinal canal?
A
Inguinal ligament
19
Q
What is the roof of the inguinal canal?
A
Lowermost fibres of TA and IO that have come off the lateral part of the inguinal ligament and are ARCHING UP OVER AND DOWN (spermatic cord passes underneath the arch) to insert into the pubic crest as a conjoint tendon.
20
Q
Anterior wall of inguinal canal
A
EO aponeurosis, IO muscle (lat)
21
Q
Posterior wall of inguinal canal
A
Trasversali fascia and conjoint tendon of IO and TA (med)
22
Q
What are the layers of the spermatic cord?
A
- Internal spermatic fascia from TF
- Cremasteric muscle and fascia from arching fibres of IO and TA (contract testes in cold weather)
- External spermatic fascia from EO
23
Q
Where is the weakest part of the abdominal wall through which abdominal contents are likely to directly herniate?
A
“Inguinal triangle”: behind inguinal canal (posterior wall), between inferior epigastric artery and rectus abdominus
24
Q
Posts major - function
What happens if PMaj is weak?
A
Flexor of vertebral column, maintains erect spine.
Weakened PM -> lumbar lordosis
25
How foes Psoas major organise the neurovascular structures?
Nerves within, vessels behind, sympathetic trunk in front
26
Attachments of psoas major
Sits in paravertebral gutters, immediately adjacenet to vertebral column.
Attaches from lower border of T12 to upper border of L5
Attaches to vertebral bodies, disks and medial ends of transverse processes. FIRM ATTACHMENT!
Distally passes underneath inguinal ligament to insert onto lesser trochanter of femur with iliacus
27
Quadratus Lumborum
Attachments.
Function?
edge to edge on lateral aspect of PM
Attaches to 12th rib above, tips of lumbar transverse processes, and posterior half of iliac crest below
Stabiliser of the 12th rib and lateral flexor
28
Iliacus attachments
Below QL
Attaches to the smooth fossa of the iliac bone of the pelvis (inverted triangle shape, below QL and edge to edge laterally w Psoas major)
Distally fibres converge w posts major to insert onto lesser trochanter of femur
29
What are the layers and compartments of the thoracolumbar fascia and what muscles are enclosed within?
Layers:
Anterior: attaches to front of lumbar transverse process
Middle: attaches to tip of transverse process
Posterior: attaches to tip of spinous process
Anterior compartment: quadratus lumborum
Posterior compartment: erector spinae
30
WHich anterior abdominal muscles attach to the thoracolumbar fascia, and where?
Line of fusion of all the thoracolumbar fascia
| TA and IO attach to lateral edge BUT EO DOESNT extend that ffar (interrupted by lat dorsi)
31
When you have a lump in the groin, what is this commonly?
Psoas abscess from lumbar Tb -> Tb infection in vertebrae breaks into psoas and tracks down between psoas muscle and fascia to the groin
*Psoas major is contained within its own fascia
32
What do the kidneys sit against and what vertebrae are they related to?
Which sits lower?
Against QL, from T12 to L3, anterior to rib 12
R slightly lower down because liver sits above it
33
Size of a kidney
10cm long
5cm wide
2.5cm thick
34
What is the asymmetry of the adrenal glands?
R: adrenal gland is triangular in shape and sits at apex of R kidney
L: Crescent shaped, sitting at superomedial aspect of L kidney
35
What is the lobular organisation of the kidney?
Outer cortex is a continuous band of pale tissue surrounded by fibrous capsule which is surrounded by peri-renal fat
Inner medulla: discontinuous darker pyramids with apex towards hilum and base towards outer cortex
36
What is the order of structures in the kidney hilum?
Vein, artery, ureter from front to back within fat
37
What is an accessory renal artery?
Occur in 20% of people - arteries from lower down (kidneys migrated up during development) that have persisted
Hazard in surgery
38
Which renal vein crosses what to get from kidney hilum to IVC?
L renal vein crosses over abdominal aorta to get to L side of IVC
39
Which renal artery crosses what to get from aorta to kidney hilum?
R renal artery crosses behind IVC to get to R kidney hilum (don't want to squish a vein) then divides into 5 discreet segmental arteries (each supply their own discreet segment of kidney)
40
What is the organisation of the renal pelvis as it penetrates the kidney?
Renal pelvis is the dilated upper part of ureter in the hilum of kidney
Apex of medulla -> minor calyces
2-3 minor calyces -> major calyces
2-3 major calyces -> renal pelvis
41
Blood supply to ureters
Blood supply from any adjacent artery throughout their course
42
Course of the ureters
Descend from kidneys, with symp trunk on Psoas major, lateral to tips of lumbar transverse processes
Tip over pelvic brim to enter base of bladder
43
Sites of narrowing of ureters
1. at renal pelvis in hilum (large kidney stones lodge here)
2. Pelvic brim/over iliac artery
3. Oblique passage through bladder wall
44
How long is a ureter?
| How long is the oesophagus?
ureter: 20-30cm long
esophagus: 25cm long
45
What sort of cell type lines the oesophagus?
Stratified squamous epithelium - tough!
46
What prevents food from refluxing into oesophagus from stomach?
R crus wraps around esophagus as it passes through the muscular part of diaphram at the level of T10
47
Arterial supply to:
Cervical esophagus
Thoracic esophagus
Abdominal esophagus
CE: Inferior thyroid a
TE: Oesophageal branches from aorta
AE: L gastric a from aorta
48
Venous drainage of:
Cervical esophagus
Thoracic esophagus
Abdominal esophagus
CE: Brachiocephalic (systemic) v
TE: Azygous
AE: Portosystemic anastamoses
49
Lymph drainage of:
Cervical esophagus
Thoracic esophagus
Abdominal esophagus
CE: Deep cervical nodes
TE: medistinal nodes
AE: Pre-aortic nodes
50
2 openings of stomach
Esophageal/cardiac orifice: esophagus opens into stomach
| Pyloric: stomach opens to duodenum
51
Parts of stomach from proximal to distal
Fundus (blind ending, gas bubble)
Body: cardiac orifice to angular notch in lesser curvature
Pyloric antrum: funnels down to pyloric canal
Pyloric canal: most tubular and distal; thick muscular wall forms pyloric sphincter
52
What is the stomach lined by?
Rugae/gastric folds that increase in prominence distally
53
What shape is the duodenum and what is it intimately related to?
C-shaped
| surrounds the head of the pancreas
54
Where are the duodenal papilla (major and minor) located and what opens into them?
2nd vertical part of duodenum
Major: 1/2 way down on posteromedial wall. common bile duct and pancreatic duct
Minor: Inch above the major duodenal papilla , opening to accessory pancreatic duct
55
How long is each part of the duodenum
Duodenal cap: 2in
2nd vertical: 3in
3rd transverse: 4in
4th: 1in
56
1st part of duodenum - location
Directed up and back to posterior abdominal wall to become retroperitoneal
on R Psoas, medial to R kidney
57
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Transverse duodenum (3rd part): where is it?
What does it cross over and what crosses over it?
```
runs horizontally from R to L Psoas, across lumbar vertebral column and aorta and IVC at level of L3
SMV and SMA hook over the front of it, along with "The mesentery" from duodenum and ilium overlying it
58
How long is the Si and what proportion is which part?
4-6m
First 2/5ths jejunum in LUQ
Last 3/5ths ileum in RLQ
59
What vessels are transmitted within "The Mesentary" and how do they change between proximal and distal SI?
Proximal arterial loops: vascular arcades
Distal vertical vessels heading to the tube = vasa recta
Jejunum has fewer arcades and longer vasa recta
Ileum has more arcades and shorter vasa recta
60
How to ileum and jejunum differ?
Jejunum: larger in diameter
Larger and more numerous folds
Less fat in mesentery (vessels more visible)
Fewer arcades and longer vasa recta
61
Where does the SI end?
At the iliocaecal junction: valve/sphincter that controls passage of entry of contents from SI to LI
62
Main functions of:
Duodenum
SI
LI
Duodenum: Digestion, absorption
SI: Absorption
LI: water/ion absorption to form faeces
63
Tenia colae
3 longitundinal muscle bands on surface of LI that function in peristalsis
Shorter than tube so gather tube into haustrations/sacculations
64
Epiploic appendices
Fatty tags hanging off LI
65
What are the component parts of the LI
Caecum, appendix
Ascending colon -> hepatic/R colic flexture
Transverse colon -> splenic/L colic flexture
Descending colon
Sigmoid colon (s shape)
REctum
66
What aspects of the appendix are constant vs variable?
Constant: point of attachment to caecum at intersection of 3 tenia coli
Variable: length and location of tip (retrocaecal appendix is common - tucked up behind caecum)
67
Falciform ligament
Divides R and L lobe of liver; double fold of peritoneum that reflects off diaphragmatic surface of liver and connects it to interior aspect of anterior abdominal wall.
68
Coronary ligament
Reflection of peritoneum off superior aspect of diaphragmatic surface of liver and onto underside of diaphragm
Laterally on each side it becomes the R and L triangular ligaments.
69
Ligamentum teres
obliterated umbilical vein which used to carry oxygenated blood from placenta to foetus.
Hangs down off interior aspect of liver below free edge.
Forms the Inferior L stem of the H on the visceral surface of liver.
70
What visceral impressions are embedded in the visceral surface of the liver?
L: esophagus, gastric,
R: Kidney, duodenum, colon
71
What are the components of the H on the visceral suface of the liver and what are the smaller lobes that are formed?
R stem: IVC superior/posterior and gallbladder inferior/anterior
L stem: Lig venosum superior and lig teres inferior
Cross-piece: hilum
Superior lobe: caudate lobe (between venosum and IVC)
Inferior lobe: quadrate lobe (btwn quadrate and gall bladder)
72
What is the structure within the porta hepatis?
Anterior: Artery-L and Bile duct-R
*Portal a/v divides into R and L portal a/v upon entering the hilum
Posterior: portal vein (div into R and L portal v)
+nerves and lymphatics (can't be seen)
73
what is the venous drainage of the liver?
3x Hepatic veins - empty directly into IVC (not in port hepatic)
74
What is the course of the common bile duct to the duodenum?
Descends in free edge of lesser momentum
Passes behind 1st part of duodenum
Tucks into groove between the head of the pancreatic head and second part of duodenum
Joins pancreatic duct and empties into major duodenal papilla in 2nd part of duodenum
75
What is the branching of the hepatic ducts and bile duct?
R and L hepatic ducts -> common hepatic duct
Cystic duct from gallbladder + common hepatic duct -> common bile duct ... then joins pancreatic duct before entering major duodenal papilla
76
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How do the different parts of the pancreas relate to other abdominal structures?
Head
Uncinate process
Neck
Body
Tail
```
Head- within C shaped curve of duodenum
Uncinate process: lies anterior to 3rd part of duodenum and posterior to the superior mesenteric vessels
Neck: lies anterior to superior mesenteric vessels
Body: above DJ flexure
Tail: points to hilum of spleen
77
What ribs are related to the spleen?
9,10,11
78
What does the ventral mesentery of the primitive gut tube become?
The falciform ligament connecting the liver to anterior abdominal wall
79
What structures are secondarily retroperitoneal and what does this mean?
Unpaired structures that originally had a mesentery in development that was resorbed.
Middle layer, in front of paired retroperitoneal structures (adrenals, kidneys, ureters)
Duodenum, pancreas, bile duct
asc and desc colon
80
What structures are intraperitoneal?
Stomach
ileum and jejunum, caecum
transverse and sigmoid colon
81
What is the mesentary of the SI called and where does it attach?
"The Mesentary"
From ileocaecal junction, up diagonally to DJ flexture
Crosses in front of 3rd part of duodenum, aorta, iVC
82
What is the mesentary of the transverse colon called and where does it attach?
Transverse mesocolon
| From hepatic to splenic flextures, across pancreas and 2nd part of duodenum
83
What is the mesentary of the sigmoid colon called and where does it attach?
Sigmoid mesocolon
| inverted V shape in LLQ/iliac fossa
84
What does the greater omentum do?
Leaves the greater curvature of the stomach, descends in front of abdominal contents, then turns back on itself, passes behind and sticks to transverse mesocolon before heading to posterior abdominal wall
85
What does the lesser omentum do?
Connects lesser curvature of stomach to undersurface/visceral surface of liver, splits and surrounds liver, then reconvenes as coronary and triangular ligaments then goes to line undersurface of diaphragm
Free edge of lesser omentum=Hepatoduodenal ligament: where stomach stops and duodenum begins: portal triad runs in this from portahepatis to posterior abdominal wall
Behind the free edge is the space behind the stomach = Lesser sac/Omental bursa
86
Where does the lesser sac communicate w the greater sac?
At the epiploic/omental foramen of Winslow (behind the free edge of the lesser omentum)
87
What are the branches of the abdominal aorta:
Anterior (unpaired): coeliac, SMA, IMA
Lateral (paired): adrenals, renals, gonadal
Posterior (paired): phrenic, lumbar
88
At what level does the coeliac trunk come off the abdominal aorta?
What does the coeliac trunk supply
```
T12 (immediately after it passes through hiatus in diaphragm)
Solid viscera (Liver, gall bladder, pancreas, spleen)
GIT from abdominal esophagus to major duodenal papilla of duodenum
```
89
What are the 3 main branches of the coealiac trunk?
L gastric a
Spenic a
Common hepatic a
90
What does the L gastric a supply?
esophageal branches to abdominal esophagus
| runs along lesser curvature of stomach (L side)
91
What does the splenic a supply?
Runs along top of PANCREAS (supplies pancreas body and tail)
Torturous path behind stomach to hilum of SPLEEN
Short gastric branches to FUNDUS of stomach
L gastroepiplic branches to L side GREATER CURVATURE of stomach
92
What does the common hepatic a supply?
Turns Right off coeliac trunk, then divides giving an ascending branch = PROPER HEPATIC A:
Gives off R GASTRIC A -> R side lesser curvature of stomach
Ascends and divides into R and L HEPATIC A to supply R and L functional halves of liver.
R hepatic a gives off CYSTIC A to gall bladder
Descending branch = GASPRODUODENAL A
Gives off SUPERIOR PANCREATODUODENAL A to pancreas head and duodenum before major duodenal papilla
And gives off R GASTROEPIPLOIC A to R side greater curvature of stomach
93
At what level is the SMA given off and what does it supply?
L1
| From major duodenal papilla to just proximal of splenic flexure (transverse colon)
94
What branches does the SMA give off?
Inferior pancreaticoduodenal branch given off immediately to supply duodenum and head of pancreas
Enters the root of The Mesentery
-> L jejunal or iliac branches -> vascular arcades -> vasa rectum
-> R colic branches -> feed into marginal artery parallel to colic tube -> short vertical vessels to the tube
95
What does the IMA supply and where is it given off?
Off at L3
| Supplies everything distal to and including splenic flexure, to rectum and proximal anal canal
96
Branches of IMA
Heads diagonally down to LLQ and gives off series of colic branches which feed into marginal artery parallel to colic tube -> short vertical vessels to the tube
After colic branches, has changed name to superior rectal artery and heads down to pelvis
97
What is the venous drainage of the abdomen?
GIT (excluding liver) deoxy blood drains through portal system into portal vein which goes to liver, then drains through hepatic veins into IVC
Liver is drained by hepatic veins into the IVC
Blood from abdominal walls and diaphragm, adrenals, rentals and gonads drain directly into IVC
98
What is the pattern of venous drainage (branching) into portal vein?
IMA joins to splenic v, then splenic vein joins with SMA to form portal vein which splits into R and L portal vein before emptying into liver
99
What is portal hypertension?
When portal venous pressure rises because it isn't being emptied into liver due to liver fibrosis (chronic inflammation or alchohol damage) so it backs up behind the liver.
100
What is the clinical significance of the portal vein being valaveless?
If portal vein can't empty into liver, reverse flow can occur so blood can look for alternate route of draining into IVC (portosystemic anastomoses)
101
What are the various sites of portosystemic anastamoses
1. lower oesophagus: oesophageal veins draining into portal system enlarge and try to push blood into azygous tributaries that normally drain middle 1/3 of oesophagus
2. anal canal: superior rectal vein engourages and tries to push blood into middle and inferior rectal veins draining into systemic circulation
3. umbilical: veins of ligament teres open up and try to shunt blood into superior and inferior epigastric veins
4. Where an abdominal viscus draining into the portal system (Asc. and desc. colon and bare area of liver) sit against posterior abdominal wall/diaphragm draining into the IVC.
102
Pain referral of gut
visceral pain
unpaired structures proximal to mid-sigmoid colon referred to midline, dermatomes T6-L2
Unpaired structures from mid-sigmoid down referred to perineal region, dermatomes S2-4
103
PS innervation of gut
vagus to foregut and midgut
| splanchnics to hindgut
104
Symp innervation of gut
foregut
midgut
hindgut
preganglionic fibres pass to sympathetic ganglia clustered around unpaired branches of aorta and renal arteries, then post-ganglionic fibres pass to the gut derivatives.
T6-9: foregut
T8-12: midgut
T12-L2: hindgut
