Abdomen Flashcards
what is the transpyloric plane
Midway between jugular notch & Pubic symphysis
Approx L1
Origin & insertion external oblique M
Lower 8 ribs
Fleshy insertion onto outer lip of iliac crest
Lumbar triangle of petit borders
Anterior - posterior border of Ext Oblique M
Floor = internal oblique M
Inferior border = iliac crest
Posterior border = anterior border of lat dorsi
Where does the superficial ring lie
Above & lateral to pubic tubercle in aponeurosis
Origin & insertion internal oblique m
Arises
- lumbar fasica
- intermediate area of ant 2/3rd of iliac crest
- lateral 2/3rd of inguinal lig
Inserts: tip of 9th costal cartilage and rectus sheath
Transversus abdominis origin & insertion
Arises - lateral 1/3rd of inguinal lig, anterior 2/3rd of inner lip of iliac crest, lumbar fascia, 12th rib, inner aspect of 6th CC where it interdigitates with diaphragm
Fuses with internal oblique into linea alba & conjoint tendon
Rectus abdominis origin and insertion
Medial head - in front of pubic symphysis
Lat - upper border of pubic crest
Insert = in front of 5-7th CC
What is the arcuate line
Where all abdoneurosis of abdominal muscles pass anterior - there is no posterior sheath
Contents of the rectus sheath
Rectus abdominis
Pyramidalis
Lower 6 thoracic nerves
Posterior intercostal vessels
Superior & inferior epigastric A
Blood supply of anterolateral abdo wall
Intercostals
Epigastrics
Lumbar
Deep circumflex iliac A (at risk in gridiron incision)
Lymph drainage of anterorlat abdo wall
Pectoral group of axillary nodes
Superficial inguinal nodes
Mediastinal
Nerve supply of rectus abdominis
Lower intercostal & subcostal N T7-12
Nerve supply of external oblique m
Lower intercostal & subcostal N t7-12
Nerve supply of internal oblique m
Lower intercostal, subcostals, T7-12, iliohypogastric & ilioinguinal
Nerve supply of transversus abdominis
Lower intercostal, subcostal, T7-12, iliohypogastric, ilioinguinal
What is transmitted in the inguinal canal b/w men & women
M = spermatic cord, ilioinguinal N
F = round lig, ilioinguinal N
What is the inguinal canal
A oblique intermuscular slit approx 4cm long, from deep to superficial ring
What are the walls of inguinal canal
2MALT
Roof = internal oblique, transversus abdominis
Anterior wall = external oblique + internal oblique aponeurosis
Floor = inguinal & lacunar lig
Posterior wall = conjoint tendon, weak transversalis
Where is the deep inguinal ling
1.25cm above midpoint of inguinal lig
Does the ilioinguinal N pass in the spermatic cord
No passes through the inguinal canal ABOVE the cord
what does the ilioinguinal N supply
Skin of inguinal region
Upper thigh
Ant 2/3rd scrotum
Root of penis
Hasselbach triangle boundaries
Medial - lateral border of rectus
Lateral - inferior epigastric A
Inferior - inguinal lig
What defines indirect hernia
Lateral to inferior epigastric A
What denies direct hernia
Medial to inferior epigastric A
What is in the medial umbilical lig
Obliterated urachus
What is in the lateral umbilical folds
Inferior epigastric vessels
What is in the medial umbilical folds
Obliterated umbilical A
What are the coverings of the spermatic cord
Internal spermatic fascia
Cremasteric fascia
External spermatic fascia
Where does internal spermatic fascia arise
Transversalis fascia
Where does cremasteric fascia arise
Lateral part of inguinal lig, internal oblique & transversus abdominis
Where does external spermatic fascia originate
From external oblique aponeurosis
What are the contents of spermatic cord
Ductus deferens
testicular A, artery to ductus deferens, cremasteric A
Pampiniform plexus
LNs
Genital branch of genitofemoral N
Processus vaginalis
Blood supply of artery
Testicular A from aorta
Drainage of testis
Via pampiniform plexus
L = L renal V
R. = IVC
Lymph drainage of testis
Para-aortic nodes @ L2
Nerve supply of testis
Sympathetic (t10 mainly) via greater/lesser splanchni nerves
Sertoli cells
Secrete androgen binding protein
Leydig cells
Secrete testosterone
What do seminiferous tubucles open into
Rete testis
What is the mesonephros in males
Other than kidneys, mainly regresses
Remaining features - canal of epididymis, ductus deferens, ejaculatory duct, epididymal appendix
Epithelium of ductus deferens
Columnar with stereocilia
What does the paramesonephric duct form in women
Uterine tube & uterus
What are the remaining features of paramesonephric ducts in males
Appendix testis
Prostatic utricle
What passes through transpyloric plan
Spinal cord = conus medullaris
SMA leaves aorta
Pylorus of stomach
Head, neck, body of pancreas
Lower border of L1 vertebra
Kidney hilum
Fundus of GB
Cuts costal margin at 9th CC
Falciform ligament fx and content
Connect liver to supraumbilical & inferior surface of diaphragm
Contains ligamentum teres
What is ligamentum teres
Obliterated L umbi V
What connects greater & lesser sac
Epiploic foamen
What forms the greater omentum
Gastrocolic (bw stomach & transverse colon)
Gastrosplenic Lig
Lienorenal lig
What is the attachments of lesser omentum
R side of oesophagus along lesser curve to first 2cm of dudenum
L shaped liver attachment to fissure for lig venosum & porta hepatis
Right free margin
Boundaries of epiploic foramen
Upper = caudate process of liver
Lower = first part of duodenum
Post = IVC with parietal peritoneum on top
ant = R free margin of lesser omentum
What lies in the R free margin of lesser omentum
Hepatic portal V
Hepatic A
CBD (to the R of A)
What divides the supra & infracolic compartments
Transverse mesocolon
What further divides the infracolic compartment
Root of mesentry of Small Intestine *L to R at 45 degrees
What does the root of mesentry cross
aorta
IVC
R psoas
Ureter to the R iliac fossa
What does the sigmoid colon lie over
L ureter
Bifurcation of common iliac A
Inferior mesenteric vessels
Vein b/w ureter & artery
What supplies (nerve) parietal peritoneum
Spinal nerves
Intercostal
Lumbar nerves
Visceral peritoneum nerve supply
Afferent nerves which travel with autonomic nerves
What exists in the retroperitoneal space
Aorta
Ivc
Cisterna chyli
LN + vessels
Nerves (lymbar plexus, symp plexus)
Kidneys
Ureter
Pancreas
Asc & desc colon
Most of duodenum
Adrenal glands
Coeliac trunk branches
L gastric
Splenic
Common Hepatic A
L gastric A supplies
Lesser omentum to lesser curvature
Splenic A supply
Pancreas & spleen
What branches does the splenic A give rise to
Short gastric A
L gastroepiploic A
Branches of CHA
Hepatic A proper
Gastroduodenal A
R gastric A
Branches of gastroduodenal A
R gastroepiploic
Superior pancreaticoduodenal A
What makes the portal V
SMV & Splenic V behind neck of pancreas
SMA origin level
L1
Origin level coeliac trunk
T12
Branches of SMA
Inferior pancreaticoduodenal A
Jejunal & ileal branches
Ileocolic A
R colic A
Middle colic A
Ileocolic supplies
Anterior and posterior branches
Ascending colon, caecum, appendicular A, and terminal ileum
Venous drainage of midgut
SMV
Where does IMA start
L3
What are the significant branches of IMA
L colic
Sigmoidal A’s
Sup rectal A
What drains to the IMV
Superior rectal V
L colic
Sigmoidal V
Where does the iMV drain
Joins splenic V mainly
What makes up the enteric nervous system
Myenteric (auerbacher) b/w muscle layers
Submucosal (Meissner) in submucosa
What are the 3 main aperatures of the diaphragm and where do they pass
Aortic T12
Oesophageal T10
IVC T8
How does the oesophagus enter the abdomen
T10, with fibres of R crus opening to form a sling
What are the parts of the stomach
Cardiac notch
Fundus
Body
Greater, lesser curvatures
Pyloric part
What makes up the stomach bed
Posterior wall of stomach is covered by peritoneum of the anterior wall of lesser sac
Splenic A
Body of pancreas
Transverse mesocolon
L upper part of kidey
L suprarenal
Spleen
L colic flexure
Blood supply to stomach
(From coeliac trunk)
L + R gastric A = lesser
Short gastric A
L+R gastroepiploic A = greater
Stomach lymph drainage
Coeliac nodes
Nerve supply to stomach
Sympathetic (Vasomotor)
Afferent (pain)
PSNS from vagi = anterior and posterior vagal trunks
Where does the anterior and posterior vagal trunks arise
Anterior = L vagus
Post = R bagus
What does a vagotomy due to the stomach
Decrease gastric secretion
Cause gastric stasis
What are the parts of the duodenum
1st part = L1, superior
2nd = L2, desc
3rd = L3, horizontal
4th = L2, ascending
How is the fourth part fixed to the L psoas
Via a fibrous tissue & suspensory muscle of duodenum (lig of treitz)
Blood supply to duodenum
Superior and inferior pancreaticoduodenal A
In the first 2cm = hepatic, gastroduodeeal, supraduodenal, R gastric & r gastroepiploic
Features that differentiate jejunum, ileum
Jejunum = wider bore, thicker walled, arterial arcades are visible as the mesenteric fat does not stretch that far
I = peyers patches
Nerve supply to small intestines (jejunum, ileum)
PSNS = peristaliss
Symp vasoconstriction from lateral horns of T9, T10
Blood supply to jejunum
Arterial arcades from SMA
Occlusion may cause infarction, as they are end arteries
Ileum blood supply
SMA, arcades
Lymph drainage of Small intestine
Sup mesenteric nodes
Caecum blood supply
Ileocolic A => Ant, post caecal A
Appendix - how to find
Convergence of 3 taeniae coli
Where is appendix located
Posteromedial wall of caecum 2cm below Ileocolic valve
Most common position of appendix at appendectomy OT
Retrocaecal
(In the absence of pathology = retroileal)
What is the blood supply of appendix
Appendicular A, off post caecal A (from ileocolic A)
Which aspects of the colon are retro/intraperitoneal
Ascending/descending colon = retroperitoneal
Sigmoid, transverse colon = has mesentry
Blood supply of colon
SMA to asc + prox 2/3rd of transverse colon
- ileocolic, R colic, middle colic
IMA to rest
- L colic & sigmoid branches
Watershed areas of the colon
L colic flexure, b/w midgut & hindgut vessels, b/w middle colic & L colic
Lymph drainage of colon
Sup, inf mesenteric nodes
Nerve supply to colon
PSNS from vagi, pelvic splanchnics
SNS from T10-12
Where does ligamentum teres lie
In free lower margin of falciform ligament, notched on inferior border of ligament
What are the lobes of the liver
L, r, caudate (upper), quadrate
Aspects & location of gallbladder
Cystic duct - close to the.R end of porta hepatis
Neck is highest
Fundus is lowest
What lies b/w GB and fissure for lig teres
Quadrate lobe
What is in contact with bare area of liver
IVC, diaphragm
What is the falciform ligament
Remnant of ventral mesentery of fetus
What does the falciform lig contain
Lig teres
What is the lig teres
Obliterated L umbi V
What is the lig venosum
Obliterated ductus venosus
What borders the caudate lobe
IVC, lig venosum, porta hepatis
What borders the quadrate lobe
GB, lig teres, porta hepatis
What is the blood supply to the liver
2 sources
- hepatic A (from coeliac trunk)
- portal V
How does the liver drain into the IVC
Three main hepatic V
Nerve supply of the liver
Sns + vagal fibres from hepatic branch of anterior vagal trunk reach the porta hepatis via lesser omentum
What forms the CHD
R+L hepatic ducts
What forms the CBD
CHD + Cystic duct
What is the capacity of GB
50ml
Where is the fundus of GB found (surface)
9th CC tip, transpyloric plane
Blood supply to GB
Via cystic A from R hepatic A
What makes up calots triangle
Liver, CHD, cystic duct
What passes through calot’s triangle
Cystic A
Length and size of cystic duct
2-3cm in length, 2-3mm in diameter
CBD length and diameter
6-8cm , <8mm
What are the three parts of the CBD
Supra, retro and paraduodenal
Where does the CBD end
With the pancreatic duct at an angle of 60 degrees at ampulla of vater, into 2nd part of duodenum into major duodenal papilla
Where does the major duodenal papilla lie
2nd part of duodenum, 10cm from pylorus
What is the blood supply of biliary tract
Cystic A
R hepatic A
Post branch of sup pancreaticoduodenal A
Nerve supply to biliary tract
Hepatic branch of anterior vagal trunk
SNS (coeliac ganglia)
CCK (hormonal)
Afferent from t7-8
What is the role of PSNS in biliary tract
Stimulate contraction of GB & relax sphincter of oddi
How does the portal V divide in the porta hepatis
Into R+L branches in T shape
What are the sites of porto-systemic anastomosis
Periumbilical region
Lower end of oesophagus
Bare area of liver
Upper end of anal canal
Retroperitoneal areas
Areas of the pancreas
head, neck, body, tail, uncinate process
What is the fx of pancreas
Exocrine, endocrine
Blood supply to the pancreas
Splenic A
Superior, inferior pancreaticoduodenalA
Nerve supply of pancreas
Posterior vagal trunk
Coeliac plexus
SNS vasoconstrictors (via splanchnics)
Spleen ligaments
Gastrosplenic lig
Lienorenal lig
Where does the tail of pancreas lie
In lienorenal lig
Blood supply of spleen
Splenic A
Lymph drainage of spleen
Coeliac nodes
Nerve supply to spleen
Coeliac plexus from SNS only
