Abdomen Flashcards
How many regions is the abdomen divided into
9
Why do we have Camper’s and Scarpa’s fascia in the abdomen but not the limbs
The enveloping structures of the upper limb do not allow stretch but those of the abdomen do
What are the requirements for abdominal incisions
Provide direct access
Adequate exposure
Extension must be possible while minimising disruption of neurovascular supply
Muscle cutting vs splitting
Transaction causes irreversible damage/ necrosis
Splitting in direction of the fibres minimises injury
Compare longitudinal and transverse incisions
Longitudinal are preferred for exploratory laparotomy as they provide good exposure but scarring may be pronounced
Transverse give better cosmetic results and less post operative pain
Compare midline and para median incisions
Midline: through linea alba is relatively bloodless and avoid major nerves but increases risk of dehiscence and incisional hernia
Para median: made parallel to midline through rectus Sheath and gives better wound scrutiny
Give the initial steps of key hole surgery
Creation of pneumoperitoneum
Insertion of laparoscope
Placement of additional parts
What is herniating tissue
The tissue that fills the hernia eg fat, gut and/ or omentum
Where do hernias appear
Any site or weakness in the musclo-aponeurotic abdominal wall
What is te hernial sac
A protrusion or peritoneum which emerges from the hernial orifice
What are complications associated with hernias
Pain
Irreducibility
Strangulation
How common are epigastric hernias of the linea alba
Occurs in 3-5% of population
Discuss the congenital and acquired hernias of the umbilicus
Congenital: seen in newborns as anterior abdomen wall is weak at umbilical ring. Often small and close spontaneously
Acquired: develop in the obese with extra peritoneal fat, peritoneum and/or bowel protruding into hernia sac
What is a direct inguinal hernia
Always acquired
Protrudes through a weakened conjoint tendon, medial to inferior epigastric artery
Describe indirect inguinal hernia
Enters deep inguinal ring lateral to inferior epigastric artery
May be congenital due to patent processus vaginalis
Femoral hernia
Emerges through femoral canal below inguinal ligament
Irreducibility and strangulation occur more commonly due to narrow neck of canal, necessitating emergency surgery
What is the lumbar triangle
An area of weakness in posterolateral abdominal wall
Bounded by lat dorsi, external oblique and iliac crest
Which structures form the greater omentum
A fatty peritoneal fold hanging from the stomach and transverse colon
What is the purpose of the sphincter at the gastro-oesophageal junction
Prevent acid reflux
Which sex has a longer urethra
Males
Where do testicular and ovarian lymphatics drain
Para-aortic lymph nodes
What forms the pelvic floor
Levator ani
What is the largest cavity in the body
Abdominal cavity
What are the boundaries of the abdominal cavity
Bounded by the abdominal wall on all sides
Separated from the thoracic cavity by the diaphragm superiorly
Continuous with the pelvic cavity inferiorly (there is a physical separation further down at the pelvic diaphragm)
In reality what is in the peritoneal cavity
How does it differ by sex
50-100ml of fluid
Males: completely closed
Females: communication with the exterior exists via the uterine tubes, uterus and vagina (providing a possible route for infection)
What connects the greater and lesser sac
The epiploic foramen
What are the intraperitoneal spaces
Subphrenic
Subhepatic
Paracolic gutters
Rectovesical/ uterine pouch
Where are the subphrenic and subhepatic spaces
Right and left between diaphragm and liver
Hepatorenal pouch on the right of the lesser sac on the left
What is the clinical importance of intraperitoneal spaces
Potential spaces for the collection of fluid and sites of abscess formation
What does the term intraperitoneal refer to
The viscera enclosed by layers of peritoneum rather than in the peritoneal cavity itself
What features do the intraperitoneal viscera have
Suspended by mesenteries with varying levels of mobility
Which organs are intraperitoneal
Stomach Liver Gall bladder Proximal and distal parts of the duodenum Jejunum, ileum Transverse and sigmoid colon Spleen
Which organs are retroperitoneal
What features do they have
Kidneys and adrenal glands
Developed outside the peritoneal cavity
Covered only anteriorly
Which viscera are secondarily retroperitoneal
Most of duodenum
Pancreas (not tail)
Ascending and descending colon
What disadvantage can there be for the intestine being mobile
Abnormal twisting can occur (volvulus) around the axis of the mesentery leading to ischaemia
Give the 6 functions of the peritoneum
Support Lubrications Protection Absorption Healing Storage
Scared Lions Paw At Heat Sores
How does the peritoneum provide support
Physical and nutritional via vessels running in mesentery
How does the peritoneum provide lubrication
Secreting peritoneal fluid to facilitate viscera movement
How does the peritoneum provide protection
Phagocytosis and sealing infected areas to limit spread
How does the peritoneum provide absorption
Fluids and small molecules can pass through mesothelium
How does the peritoneum provide healing
Transforming mesothelial cells into fibroblasts to promote wound healing
How does the peritoneum provide storage
Greater omentum stores fat
What did Morison call the peritoneum
When
“The abdominal policeman”
1906
What is ascites
Excess fluid due to increased production of malignancy or decreased serum albumin in cirrhosis
Appears dark on CT, usually surrounding an organ/ compartment but fluid is limited only to that physical compartment
What haemoperitoneum
Blood in the peritoneal cavity due to trauma/ rupture
What is peritonitis
Inflammation (local or general)
Adhesions May develop between visceral and parietal layers
What is pneumoperitoneum
Gas in the peritoneal cavity due to perforated viscus or after surgery
Why is the peritoneum important for renal patients
Cancer patients?
Used in peritoneal dialysis to remove metabolites
Chemotherapy for ovarian carcinoma is administered here
What innervates the parietal peritoneum
Somatic spinal nerves that supply the overlying abdominal wall and therefore is sensitive to pain
What innervates the visceral peritoneum
Same autonomic nerve supply as viscera
Only stretch sensitive, NOT to pain
Describe the arterial supply to the abdomen
Supplied by abdominal aorta
2 paired lateral branches supply retroperitoneal organs
3 unpaired Anterior branches run in mesenteries
The marginal artery forms a continuous arcade along the entire Colon
Anastomoses provide collateral flow if there is an obstruction but also allow spread of infection
What drains the gut
Portal circulation which convey blood to the liver sinusoids for metabolism and detoxification
Where do hepatic veins move blood to
Inferior vena cava
What is the communication between the Portal and systemic circulations
Portosystemic anastomoses
What is a common cause of portal hypertension?
Obstruction to portal venous flow usually due to cirrhosis caused by alcoholism or viral hepatitis
What kind of valves does the portal vein have and what does this mean
NO VALVES
Increased pressure readily leads to back flow into systemic circulation
Why is portal/ hepatic circulation important when considering drug consumption
Medication that is affected by the liver must not be taken orally in order to bypass portal circulation
Name a drug that must NOT be taken orally
GTN sublingual tablets for angina
They will be affected by the liver so must Avoid portal circulation
What is referred pain
Pain that originates in one part of the body but is perceived in another part
Why does referred pain occur
General visceral afferent which respond to stimuli accompany sympathetic fibres to the same spinal cord segment. As the dermatomes are supplied by the same sensory ganglia and spinal segments, the pain is perceived as originating from the skin
Why may a gall bladder infection be felt in your shoulder?
Inflamed gall bladder will irritate the diaphragm which is detected by the phrenic nerve and pain is referred to the C4 dermatome
What are the spinal roots of the phrenic nerve
C3-5
Describe the immediate pain felt in appendicitis
It is visceral and so diffuse and poorly localised
What happens to the pain as appendicitis progresses
The inflamed viscus will come into contact with the parietal peritoneum which is supplied by somatic spinal nerves, and the pain will then become localised
Describe the direction of pain progression in appendicitis
Starts around the umbilical region (T10) and moves to right Iliac fossa
What is the mesentery like in the embryo
A dorsal mesentery runs the entire length of the GI tract connecting it to the dorsal body wall
Ventral mesentery is only present at the level of septum transversum where the stomach and liver develop
What is the mesogastrium
Mesentery that attaches to the stomach
What does “the mesentery” refer to
Refers to small bowel mesentery
Extends from duodenojejunal flexure to right iliac fossa
What is the mesoappendix
Connects appendix to small bowel mesentery
Transverse mesocolon
Connects transverse colon to posterior abdominal wall and forms floor of lesser sac
Sigmoid/ pelvic mesocolon
Connects sigmoid colon to posterior abdominal wall and contains pre-ganglionic parasympathetic fibres ascending from the pelvis to supply descending colon
What is derived from the dorsal mesogastrium
Greater omentum
Lienorenal ligament
How many layers does the greater omentum have
4 (it is 2 layers of 2 layers)
What is the greater omentum divided into
Gastrocolic and gastrosplenic ligaments
What is the lienorenal ligament
Peritoneum between spleen and posterior abdominal wall in region of left kidney
What are the derivatives of the central mesogastrium
Falciform ligament - connects ventral liver to anterior abdominal wall
Lesser omentum - connects lesser curve of stomach to liver
What is the lesser omentum divided into
Hepatogastric and hepatoduodenal ligaments
What are the 3 functions associated with the GI tract
Peristalsis
Absorption
Excretion
Where does the oesophagus go from and to
From the pharynx to the stomach
What is the oesophagus guarded by
The upper oesophageal sphincter whose relaxation is triggered by the swallowing reflex
What is dysphagia
Difficulty swallowing due to obstruction of the passage of food
What is odynophagia
Painful swallowing
What is heart burn
A burning sensation in the chest posterior to the sternum or in the epigastrium usually as a result of GORD
What is GORD
Gastro-oesophageal reflux disease
What is the LOS
Lower oesophageal sphincter
What is the diaphragmatic crura
Where the right crus forms a sling around the lower oesophagus
What is a hiatus hernia
When part of the stomach passes through the oesophageal hiatus of the diaphragm into the posterior mediastinum
What does the pylorus do
What happens if the sphincter is too lax or tight
Regulates flow of chime into the first part of the duodenum
Lax- Bile reflux may occur leading to antral gastritis and pain
Tight- gastric outlet obstruction (GOO) occurs
What can cause the pylorus to be too tight
Tumours
Peptic ulcer disease
Congenital hypertrophic pyloric stenosis
Ingestion Of foreign bodies
What comprises the small intestine
Duodenum, jejunum and ileum
Which parts of the small intestine are retroperitoneal or mesenteric
Jejunum and ileum are suspended on a mesentery
Most of the duodenum is secondarily retroperitoneal
Give the presentation of a patient with functional disease of the small intestine
Pain due to spasm Bloating Excessive flatus Diarrhoea Constipation
What are the causes of organic disease due to obstruction
Extra mural (adhesions, malignant invasion etc) Or Mural ( plain abdominal radiographs will show dilated loops of small bowls with multiple fluid levels seen on erect films)
Where does the large intestine span from and what is it comprised of
From ileocaecal valve to anus
Comprising the caecum, appendix, ascending, transverse, descending and sigmoid colon, rectum, and anal canal
What are the outer longitudinal muscles of the large intestine? Where is this different?
It exists as 3 bands: the Taeniae coli. These produce the characteristic sacculations or haustrations
Not in the appendix, rectum and anal canal
What are the appendices epiplociae
Peritoneal tags filled with fat
Name 3 benign diseases of the large intestine
Inflammatory bowel disease (eg Crohn’s disease which affects other parts of the GI tract and ulcerative colitis which only affects the colon)
Diverticular disease (in descending and sigmoid colon)
Polyps (fleshy protrusions arising from colonic mucosa)
What does colonic diverticula consist of
Mucosal herniation through thickened muscle
Discuss colorectal adenocarcinoma
3rd most commonly diagnosed carcinoma after lung and breast
Largely preventable by early detection by colonoscopy
Surgical resection remains the definitive treatment modality and may require stoma formation for discharge of colonic contents
Differences between ileum and jejunum
Jejunum: Upper 2/5 Umbilical region Fewer vascular arcades Less fat in mesentery Thick vascular mucosa Few lymphoid follicles Tall villi
Ileum: Lower 3/5 Suprapubic region and pelvis Thin pink walls and narrower lumen Complex vascular arcades More fat in mesentery Short villi Peyer’s patches
What supplies the muscles of the abdominal wall
Where do they drain
T7-12 and L1 (ilioinguinal)
The neurovascular bundle runs between the internal oblique and trans versus abdominis
Above the umbilicus they drain to the pectoral axillary nerves
Below the lymph drains to the superficial inguinal nodes
What are the boundaries of the inguinal canal
Posterior: transversalis fascia laterally and conjoint tendon medially
Anterior: external oblique aponeurosis
Roof: fibres of internal oblique and trans versus abdominis forming conjoint tendon
Floor: inverted edge of inguinal ligament and lacunar ligament
Where is the entrance and exit of the inguinal canal
What is important about this oblique passage
What does the canal transmit in women
Entrance: deep ring
Exit: superficial ring
Prevents abdominal contents from pro lapsing through canal when intra abdominal pressure is raised
The round ligament
What passes through the inguinal canal in men
Vas deferens with its artery and testicular vessels
Spermatic cord
Where is the abdomen
The area between the diaphragm and pelvis, bound by the anterior and posterior abdominal walls
What forms the semi rigid frame of the posterior abdomen
The vertebral column
What is the main flexor of the spine
Name 3 other muscles that also move the trunk
Rectus abdominis
External oblique
Internal oblique
Tans versus abdominis
What lines the abdominal cavity
Parietal peritoneum
What are the parts of the abdominal viscera are suspended on the mesentery
Stomach Jejunum Ileum Transverse colon Sigmoid colon
How does the mesentery form
As intestinal loops invaginate into the wall of the embryonic peritoneal sac with their attached nerves and vessels, a peritoneal fold is formed
Where does the right side of the stomach lie due to embryonic rotation of the gut
Where does the caecum lie
Posteriorly
In the right iliac fossa
How does the blood supply of the abdominal viscera arise
How are the mid, hind, and fore guts supplied
From the abdominal aorta via unpaired branches
The coeliac trunk supplies the foregut
The superior mesenteric artery supplies the midgut
The inferior mesenteric artery supplies the hindgut
What does the foregut include
Stomach Part of duodenum Liver Gall bladder Pancreas Spleen
What is the midgut
From part of duodenum to 2/3 along transverse colon
Veins draining the blood from the gut form the what
Portal venous system which conveys nutrient rich blood to the liver for processing
What does the hepatic vein do
Returns detoxified blood to the systematic system via the IVC
Where is the IVC in relation to the liver
Posterior to liver
Name 2 notable sites of portosystemic anastomoses
Gastro-oesophageal junction
Distal rectum
What can cause portal venous hypertension
What can it lead to
Cirrhosis of the liver
Formation of oesophageal varices which may result in life threatening haemorrhage
What is the foramen of Winslow
AKA epiploric foramen
The entry from the greater sac to the lesser sac
How is the lesser peritoneal sac created
Where does it lie
What is it closely related to
Embryological rotation
Lies posteriorly
Pancreas and splenic vessels
What lies within the loop of the duodenum
Pancreas
How do bile and pancreatic secretions enter the duodenum
At the ampulla of Vater
Where does the duodenum become the jejunum
The duodenojejunal flexure
Where is the ileocaecal junction
Right iliac fossa
What is the arterial supply of the kidneys
What about venous drainage
Via paired renal arteries directly from aorta
Via renal veins into IVC
Describe the path of the urethra in males
From bladder it passes through the prostate then through the perineal next brand surrounded by the sphincter urethrae
Urethra then enters the bulb of the corpus spongiosum, becoming first the spongy Urethra and then the penile urethra to end at the external urethral meatus
It is joined by ducts from seminal vesicles and prostate gland
What is the urethra a conduit for
Urine and semen
How does the female urethra compare to Male
Where is it in relation to the vagina
Female is much shorter
Anterior to the vagina
Where does the uterus lie in relation to the bladder and rectum
Posterior to bladder and and anterior to rectum
What is the pouch of Douglas
The rectouterine pouch
What supplies the pelvis mostly
Internal iliac artery
Briefly describe the descent of the testes
From the posterior abdominal wall through the inguinal canal in the anterior abdominal wall
Where do the lymphatics from the testes and ovaries drain to
Para-aortic lymph nodes
Where does the peritoneum lie
Inferior and superior to the pelvic floor
What forms the pelvic floor
Levator ani muscle which arises from the lateral abdominal wall to join its opposite number in a midline raphé
What lies between levator ani and ischial tuberosity
What is it filled with
Give a fact about it
Ischioanal fossa
Fat
It is liable to infections and access formation from the anal canal
What is the penis comprised of
2 copora cavernosa
The urethra is covered by the corpus spongiosum which continues as the glans penis distally
What happens to the corpora cavernosa posteriorly
They divide to attach to the ischiopubic rami where they are covered by the ischiocavernosus muscle
Describe the scrotum
A thin pouch of skin containing the testes, each suspended by a spermatic cord containing structures that accompanied the testes during its descent in development
What are the labia
Where does the urethra open
Outer folds to the entrance to the vagina
Anteriorly
What is anterior the the urethral opening
What is it comprised of
The clitoris
A glans and two corpora cavernosa which are smaller but homologous to those in the penis
Describe the path of the pudendal nerve
What does it supply
Which artery supplies the same structures
From the sacral plexus and leaves the pelvis via the greater sciatic foramen
It crosses the sacrospinous ligament and enters the peritoneum through the lesser sciatic foramen
Muscles of the area and is sensory to the skin of the anus, perineum, and external genitalia
Internal pudendal artery
Where does the internal pudendal artery come from
Internal iliac artery
What lies half way between the suprasternal notch and the pubic symphysis
The transpyloric plane
Which neurovascular bundles run between the internal oblique and transversus abdominis
T7-L1
Can the obliques help expiration
They push the diaphragm up in deep expiration and coughing
How are the obliques and transversus abdominis related anteriorly (briefly)
They aponeuorse anteriorly forming the linea alba
What does rectus abdominis lie within
Anterior and posterior layers of the rectus sheath formed by other muscles
What does the arcuate line mark
The free lower edge of the posterior layer of the rectum sheath
What forms the inguinal ligament
What does this ligament attach to
The lower aponeurotic edge of the external oblique
The anterior superior iliac spine and pubic tubercle
What is the superficial inguinal ring
A triangular opening on the external oblique aponeurosis above the public crest
Describe the conjoint tendon
Formed from internal oblique and transversus abdominis
It is attached to the pubic crest and pectineal line
It supports the superficial ring
What is the inguinal canal
An oblique canal lying above the medial half of the inguinal ligament
It transmits the spermatic cord in the Male and the round ligament in females
Where does the deep inguinal ring lie
Lateral to the inferior epigastric artery
Why does much of the abdominal cavity lie under the ribs
The domes of the diaphragm arch high above the costal margin
What is the posterior abdominal wall formed of
Ribs 9,10,11 and 12 posterior to the diaphragm and all five lumbar vertebrae
Iliac bones
How are the lumbar vertebrae curved
Combed forward so push into the abdomen
Which abdominal organs are housed in the pelvic cavity
Sigmoid colon and ileum
On a slim person where does the umbilicus lie
Opposite L3
Other than the pylorus, what lies in the transpyloric plane
From posterior to anterior:
L1 vertebra End of spinal cord Origins of portal vein and superior mesenteric artery Renal hila Neck of pancreas Second part of duodenum Duodenojejunal flexure Tips of 9th costal cartilages Fundus of gall bladder
How to remember transpyloric plane
3 Neuroskeletal: L1 vertebra, end of spinal cord, 9th costal cartilages
3 ‘tubes’: portal vein and superior mesenteric artery origins, duodenojejunal flexure, 2nd part of duodenum
3 ‘organ bits’: fundus of gall bladder, neck of pancreas, renal hila
And obviously pylorus
From where does external oblique arise
Direction of fibres?
Lower eight ribs, interdigitating with serratus anterior and latissimus dorsi
Down and forwards
Where does the external oblique insert
Posterior fibres descend to anterior half of the iliac crest
Anterior fibres become aponeurotic at the anterior superior iliac spine eventually joining the linea alba or becoming the inguinal ligament. This attaches to the pubic tubercle.
From where does the internal oblique arise
Lumbar fascia
Anterior 2/3 of iliac crest and lateral 2/3 of inguinal ligament
What happens to the fibres of the internal oblique as the my leave the inguinal ligament
Arch over inguinal canal to join lower fibres of transversus abdominis to form the conjoint tendon
Origin of of transversus abdominis
Inner surfaces of lower 6 costal cartilages (interdigitating with diaphragm),
lumbar fascia,
anterior 2/3 of iliac crest
and
lateral Half of inguinal ligament
How do the 2 bellies of rectus abdominis arise
Where do they insert
As two heads from the pubic symphysis and pubic crest
Anterior aspects of 5-7th costal cartilages
What forms the rectus sheath
The aponeuroses of the other abdominal muscles
Where does the linea alba end
Pubic symphysis
What happens to the internal oblique aponeurosis
Divides into 2 layers to enclose the rectus muscle before rejoining and fusing with the other aponeuroses in the midline
The transversus abdominis fuses with the posterior layer and the external oblique with the anterior layer
How is the anterior rectus sheath attached to the rectus muscle
By transverse tendinous intersections
Where are the tendinous intersections on the rectus abdominis
What forms the six pack
One at xiphisternum
One at umbilicus
One in between
Intervening muscle fibres
What happens to the rectus sheath below the umbilicus
3-4cm below all three aponeuroses pass anterior to the rectus abdominis muscle leaving the sheath deficient posteriorly
What is the free lower edge of the posterior rectus sheath
Arcuate line
What happens to the rectum abdominis below the arcuate line
It lies on the transversalis fascia
What supplies the rectus abdominis muscle
Where does it com from
Superior epigastric artery
Internal thoracic artery
What does the superior epigastric artery anastomose with
What is that a branch of
Inferior epigastric artery
External iliac artery
How does the superior epigastric artery run to supply rectus abdominis?
What about the inferior epigastric?
Between the posterior shealth and muscle
Runs up behind the rectum where the posterior sheath is deficient and then between sheath and muscle
Which additional nerve supplies the lower fibres of the internal oblique and transversus abdominis
L1 (ilioinguinal nerve)
Give 4 functions of the muscles of the abdominal wall
Move trunk
Depress ribs (not transversus abdominis)
Compress abdomen when coughing, sneezing and during expulsive efforts
Support abdominal viscera
What is the lymphatic drainage of the abdominal wall
Above umbilicus: pectoral group of axillary nodes
Below umbilicus: lymph drains to superficial inguinal nodes
How long is the inguinal canal
What are the boundaries
4-5cm
Posterior: transversalis fascia laterally and conjoint tendon medially
Anterior: external oblique aponeurosis, reinforces laterally by the origin of internal oblique from the inguinal ligament
Roof: fibres of internal oblique and transversus abdominis arching over the cord to form the conjoint tendon
Floor: inverted edge of inguinal ligament and lacunar ligament medially
What is the entrance to the inguinal canal
Exit?
Deep ring
Superficial ring
Describe the deep ring of the inguinal canal
Which artery is associated
An opening in the transversalis fascia above the midpoint of the inguinal ligament
The inferior epigastric artery ascends medially to it
Describe the superficial ring of the inguinal canal
An opening in the external oblique aponeurosis
It is triangular with the base medial to the pubic tubercle and the sides sloping up and laterally from the pubic tubercle and symphysis
What stops abdominal contents prolapsing through the inguinal canal
What does it transmit in females
Its oblique passage
The round ligament to the labia majora
What does the inguinal canal transmit in males
The vas deferens accompanied by its artery and the testicular vessels
As they pass along they receive a covering from every layer though which they pas
How does the ilioinguinal nerve enter the canal
What does it supply
Laterally by passing between the obliques
Skin on upper medial thigh, base of penis and the anterior scrotum or labia
What is an indirect inguinal hernia
Enters through deep ring lateral to the epigastric artery
What is the McBurney incision an example of and when is it done
A muscle splitting incision
For appendicetomy
What are Pfannenstiel incisions
Suprapubic incisions for gynaecological and obstetric operations
Describe the pain of appendicitis
Pain is initially referred to the peri umbilical region
As inflammation progresses the parietal peritoneum is involved with pain localised to the right iliac fossa
Describe a femoral hernia
Passes through the femoral canal below and lateral to the pubic tubercle
Common in women and is prone to strangulation thus requiring emergency surgery
What does exomphalos refer to
A defect in the abdominal wall with herniation of intra abdominal contents into the base of the umbilical cord
Omphalocele May form and can range from a large umbilical hernia to a very large mass containing most visceral organs
What is ectopia vesicae
Exstrophy
Defect in anterior wall of bladder and abdomen resulting in an exposed, everted posterior bladder wall
Is the umbilical hernia common
What does it involve
How is it treated
Relatively so in neonates and especially in premature babies
Herniation of small bowel but the neck of the hernia is wide and strangulation is rare
Usually closes spontaneously in first few years
What lines the walls of the abdominal cavity
What does it clothe
Parietal peritoneum
The anterior and posterior walls and inferior diaphragm
Which parts of the intestines are mesenteric
Abdominal oesophagus, stomach and first part of duodenum
Duodenojejunal junction, jejunum, ileum
Transverse colon
Sigmoid colon
What is the main region of the abdominal cavity
The greater sac
Where does the greater and lesser omentum hang down from
Greater: from greater curvature of stomach
The lesser suspends the lesser curvature of the stomach and the the first part of the duodenum
It hangs down from the liver
How is visceral pain in the abdominal cavity returned
Via general visceral afferents running with the sympathetic chain
Give 7 examples where the parietal peritoneum is reflected into visceral inside the abdominal cavity
Falciform and coronary ligaments of liver
Greater and lesser omentum
The gastrosplenic and lienorenal ligaments
Bases of mesenteries of small intestine, transverse and sigmoid colon
How is the peritoneal cavity divided for descriptive purposes
How is is separated
Into the supracolic and infracolic compartments
By the transverse colon and it’s mesentry
What are the 3 basic functions of the most dilated part of the gut tube
Ie the stomach
Storing food
Mixing food with gastric secretions to form chyme
Controlling discharge to the small intestine via the pylorus
What level Does the oesophagus enter the stomach
T10
6 reasons to prevent gastro- oesophageal reflux
- Lower oesophageal sphincter
- Diaphragmatic crura
- The angle of His
- The phreno oesophageal ligament
- Lateral pressure of the walls on the intra abdominal oesophagus
- The apposition of rosette like mucosal folds at the gastro oesophageal junction
How does the diaphragmatic crura help prevent reflux
The encircling fibres of the right crus exert a radial pressure on the lower oesophagus
This is the pinchcock effect
Describe the angle of His
It is the acute angle of entry of the oesophagus into the stomach and helps to form a flap valve
Describe the phreno- oesophageal ligament
Formed of thickened bands of elastin rich connective tissue, which effectively tethers the oesophagus to the diaphragm
Which vessels supply the stomach
All 3 arteries from the coeliac trunk
Venous drainage is to portal system
What does the left gastric artery supply
Lower oesophagus and lesser curvature
What does the splenic artery supply
It gives the short gastrics which supply the fundus of the stomach and the left gastroepiploric which runs down the greater curvature
What does the common hepatic give
Which arises first
The right gastric and gastroduodenal, which gives right gastroepiploric
Either
What is the sympathetic flow to the stomach
Where does symphony drain
Via greater splanchnic nerve via coeliac plexus
Along arteries to pre aortic coeliac nodes
Describe the lesser omentum
A double fold of visceral peritoneum which extends from the liver to the lesser curvature and first part of duodenum
It’s free edge forms the anterior boundary of the epiploric foramen and contains the HPV, Common bile duct, and hepatic artery
What order are the vessels in the free edge of the lesser omentum arranged in
HPV ( posterior)
Common bile duct (right)
Hepatic artery (left)
Where does the root of the mesentery lie
What happens to it
Where does it end up
Opposite the left side of L2 at the duodenojejunal flexure
It then crosses in front of the third and fourth parts of the duodenum, aorta, IVC and right ureter
In front of the right sacroiliac joint
How long is the mesenteric root
15cm
How long is the small intestine
6m
What does the superior mesenteric artery supply
2nd half of duodenum, all of the small intestine, and large intestine up to 2/3 along the transverse colon
Give 5 of the branches of the superior mesenteric artery
What does each supply
Inferior pancreaticoduodenal artery - supplies duodenum beyond the middle of its second part
Middle colic artery - supplies transverse colon
Jejunal and ileal branches
Right colic artery - supplies ascending colon
Ileocolic artery - divides into anterior and posterior caecal arteries
What does the posterior caecal artery give
The appendicular artery
How are mesenteric artery branches connected in the mesentery
How do these change across the mesentery
By vascular arcades
There are fewer arcades in the jejunum and they are long and straight
There are multiple complex arcades in the ileum with short straight vessels
How is the submucosa of the jejunum and ileum arranged?
Why?
they are arranged into semi circular folds
To avoid absorption
How is lymphoid tissue arranged in the GI tract
Increases down tract
Where are Peyer’s patches found
What are they
In the submucosa of the ileum
Clusters of lymphocytes
Lymph from intestine walls drains where
Via pre aortic nodes to the cisterna chyli
Where does the large intestine extend from
How long is it
From caecum to anus
1.5m
What are the main features that distinguish the large intestine from the small intestine
Taeniae coli - condensation of longitudinal muscle into 3 bands
Haustra/ sacculations - as longitudinal muscle is shorter then rest of the wall
Appendices epiploricae - small tags of fat projecting from the wall
What does the large in testing consist of
Caecum
appendix
ascending, transverse, descending, and sigmoid colon and rectum and anal canal
True or false
The ileocaecal valve is formed by longitudinal muscle
False
It is formed by the circular muscle from the terminal 2-3cm of the ileum passing through the caecal wall
What is the main function of the large intestine
Absorption of water and electrolytes
How much liquid enters the large intestine every day from the small intestine
How much is excreted
1 L
Less than 100 mL
Describe the peristalsis of the large intestine
Not a frequent continual action instead it is more periodic
What are the three branches of the inferior mesenteric artery
Left colic - supplies transverse and descending colon
Sigmoid branches - supply sigmoid colon
Superior rectal - supplies rectum and anastomoses with the middle and inferior rectal arteries ( from internal iliac artery)
What does the marginal artery consist of
Anastomoses between ileocolic, right, middle and left colic arteries Resulting in a continuous arterial line at the margin of the large intestine from the caecum to the rectum
How does lymphatic drainage compare from the large to the small intestine
The same principles apply
Drainages from large is first to the nodes in the mesentery then to the pre aortic nodes on the posterior abdominal wall before reaching the cisterna chyli
What arteries supply the upper rectum and anal canal
What is the venous drainage
Superior rectal arteries
Drain to portal vein via superior rectal veins
middle and inferior rectal arteries are branches of internal iliac artery. What does this mean for the corresponding venous drainage
What is this
Venous drainage is to the internal iliac veins which are systemic
A site of portosystemic anastomosia
When can Peritonitis occur
What are the signs
When there is bacterial contamination during surgery or when the gut ruptures as a result of infection and inflammation allowing gas, gastric contents, bile or faecal matter to enter the peritoneal cavity
Pain in overlying dermatome and rigidity in the anterior abdominal wall
What is ascites
When May this occur
XS fluid in the peritoneal cavity
Secondary carcinoma or cirrhosis
What is GORD
What are symptoms
What can be a contributing factor
What may it be associated with
Gastro oesophageal reflux disease
Reflux of gastric contents into the oesophagus causing heartburn and acid regurgitation
An incompetent cardiac sphincter
Hiatus hernia
Is peptic ulceration common?
What can happen
Yes
Posterior peptic ulcers may erode into the splenic artery and cause torrential bleeding
Gastric contents may also enter the lesser sac
True or false
Pyloric stenosis is only ever congenital
False
Can be acquired
When is congenital pyloric stenosis most common
What is a common symptom
How can this be acquired
In boys in early weeks of life
Projectile vomiting
Acquired cases are caused by scarring from peptic ulceration
True or false
carcinoma of the stomach has a good prognosis
False as it is often technically impossible to ensure complete removal of involved lymphatics due to extensive drainage
What can happen if an inflamed appendix is not treated
What are the initial symptoms of appendicitis
Then what happens
It may lead to thrombosis of the appendicular artery with subsequent necrosis and perforation
Pain is referred to the T 10 dermatome around the umbilicus
As the inflammatory process extends it will directly irritate the overlying parietal peritoneum which is supplied by somatic nerves.
pain will then be felt in the right Iliac fossa
True or false the appendix is on mesentery
What does this mean
True
It is mobile and it’s different positions may lead to difficulty in diagnosis
Classically what is the surface marking of the appendix
McBurney’s point
Which is a third of the way along the line from the anterior Superior iliac spine to the umbilicus
What is Meckel’s diverticulum
How common is it
Describe it
The embryological remnants of the vitellointestinal duct connecting the gut tube to the yolk sac
In 2% of people
Typically 3 to 5 cm long it is found within 100 cm of the ileocecal valve.
It lies on the anti-mesenteric border of the bowel and can become inflamed
What else must be considered before diagnosing appendicitis
Meckel’s diverticulum
Conditions affecting other organs situated in or near the right iliac fossa including ectopic pregnancy
What side is the appendix on when a person has situs in versus
The left wall
Other than situs in versus when may the appendix be in an abnormal position
Congenital space Malrotation of the gut
Where does the root of the mesentery lie
What happens to it
Where does it end up
Opposite the left side of L2 at the duodenojejunal flexure
It then crosses in front of the third and fourth parts of the duodenum, aorta, IVC and right ureter
In front of the right sacroiliac joint
How long is the mesenteric root
15cm
How long is the small intestine
6m
What does the superior mesenteric artery supply
2nd half of duodenum, all of the small intestine, and large intestine up to 2/3 along the transverse colon
Give 5 of the branches of the superior mesenteric artery
What does each supply
Inferior pancreaticoduodenal artery - supplies duodenum beyond the middle of its second part
Middle colic artery - supplies transverse colon
Jejunal and ileal branches
Right colic artery - supplies ascending colon
Ileocolic artery - divides into anterior and posterior caecal arteries
What does the posterior caecal artery give
The appendicular artery
How are mesenteric artery branches connected in the mesentery
How do these change across the mesentery
By vascular arcades
There are fewer arcades in the jejunum and they are long and straight
There are multiple complex arcades in the ileum with short straight vessels
How is the submucosa of the jejunum and ileum arranged?
Why?
they are arranged into semi circular folds
To avoid absorption
How is lymphoid tissue arranged in the GI tract
Increases down tract
Where are Peyer’s patches found
What are they
In the submucosa of the ileum
Clusters of lymphocytes
Lymph from intestine walls drains where
Via pre aortic nodes to the cisterna chyli
Where does the large intestine extend from
How long is it
From caecum to anus
1.5m
What are the main features that distinguish the large intestine from the small intestine
Taeniae coli - condensation of longitudinal muscle into 3 bands
Haustra/ sacculations - as longitudinal muscle is shorter then rest of the wall
Appendices epiploricae - small tags of fat projecting from the wall
What does the large in testing consist of
Caecum
appendix
ascending, transverse, descending, and sigmoid colon and rectum and anal canal
True or false
The ileocaecal valve is formed by longitudinal muscle
False
It is formed by the circular muscle from the terminal 2-3cm of the ileum passing through the caecal wall
What is the main function of the large intestine
Absorption of water and electrolytes
How much liquid enters the large intestine every day from the small intestine
How much is excreted
1 L
Less than 100 mL
Describe the peristalsis of the large intestine
Not a frequent continual action instead it is more periodic
What are the three branches of the inferior mesenteric artery
Left colic - supplies transverse and descending colon
Sigmoid branches - supply sigmoid colon
Superior rectal - supplies rectum and anastomoses with the middle and inferior rectal arteries ( from internal iliac artery)
What does the marginal artery consist of
Anastomoses between ileocolic, right, middle and left colic arteries Resulting in a continuous arterial line at the margin of the large intestine from the caecum to the rectum
How does lymphatic drainage compare from the large to the small intestine
The same principles apply
Drainages from large is first to the nodes in the mesentery then to the pre aortic nodes on the posterior abdominal wall before reaching the cisterna chyli
What arteries supply the upper rectum and anal canal
What is the venous drainage
Superior rectal arteries
Drain to portal vein via superior rectal veins
middle and inferior rectal arteries are branches of internal iliac artery. What does this mean for the corresponding venous drainage
What is this
Venous drainage is to the internal iliac veins which are systemic
A site of portosystemic anastomosia
When can Peritonitis occur
What are the signs
When there is bacterial contamination during surgery or when the gut ruptures as a result of infection and inflammation allowing gas, gastric contents, bile or faecal matter to enter the peritoneal cavity
Pain in overlying dermatome and rigidity in the anterior abdominal wall
What is ascites
When May this occur
XS fluid in the peritoneal cavity
Secondary carcinoma or cirrhosis
What is GORD
What are symptoms
What can be a contributing factor
What may it be associated with
Gastro oesophageal reflux disease
Reflux of gastric contents into the oesophagus causing heartburn and acid regurgitation
An incompetent cardiac sphincter
Hiatus hernia
Is peptic ulceration common?
What can happen
Yes
Posterior peptic ulcers may erode into the splenic artery and cause torrential bleeding
Gastric contents may also enter the lesser sac
True or false
Pyloric stenosis is only ever congenital
False
Can be acquired
When is congenital pyloric stenosis most common
What is a common symptom
How can this be acquired
In boys in early weeks of life
Projectile vomiting
Acquired cases are caused by scarring from peptic ulceration
True or false
carcinoma of the stomach has a good prognosis
False as it is often technically impossible to ensure complete removal of involved lymphatics due to extensive drainage
What can happen if an inflamed appendix is not treated
What are the initial symptoms of appendicitis
Then what happens
It may lead to thrombosis of the appendicular artery with subsequent necrosis and perforation
Pain is referred to the T 10 dermatome around the umbilicus
As the inflammatory process extends it will directly irritate the overlying parietal peritoneum which is supplied by somatic nerves.
pain will then be felt in the right Iliac fossa
True or false the appendix is on mesentery
What does this mean
True
It is mobile and it’s different positions may lead to difficulty in diagnosis
Classically what is the surface marking of the appendix
McBurney’s point
Which is a third of the way along the line from the anterior Superior iliac spine to the umbilicus
What is Meckel’s diverticulum
How common is it
Describe it
The embryological remnants of the vitellointestinal duct connecting the gut tube to the yolk sac
In 2% of people
Typically 3 to 5 cm long it is found within 100 cm of the ileocecal valve.
It lies on the anti-mesenteric border of the bowel and can become inflamed
What else must be considered before diagnosing appendicitis
Meckel’s diverticulum
Conditions affecting other organs situated in or near the right iliac fossa including ectopic pregnancy
What side is the appendix on when a person has situs in versus
The left wall
Other than situs in versus when may the appendix be in an abnormal position
Congenital space Malrotation of the gut
Is the duodenum retroperitoneal
Mostly
Where does the Common bile duct join the duodenum
What else joins here
Second part of the duodenum at the ampulla of Vater
The pancreatic duct
What are the 4 lobes of the liver
Left
Quadrate
Caudate
Right
True or false
the hepatic veins are entirely intra-hepatic
Where do they drain into
True
IVC
What makes bile
Where is it collected
Hepatocytes
It is collected by the right and left hepatic ducts, which forms the common hepatic duct which joins the cystic duct from the gall bladder to form the common bile duct
How is the common bile duct formed
The right and left hepatic duct form the common hepatic duct which joins the cystic duct from the gallbladder to form the common bile duct
How is the gallbladder related to the liver
The fundus and body of the gallbladder are firmly bound to the inferior surface of the liver
What supplies the gallbladder arterially
Cystic artery
From where does the cystic artery arise
Right branch of the hepatic artery
What connects the liver to the lesser curvature of the stomach
The lesser omentum
Describe the position of the spleen
Inferior to the diaphragm and is related to the left ninth 10th 11th ribs
It is connected to the stomach via the gastrosplenic ligament and to the left kidney via the lienorenal ligament
Give two words to sum up the functions of the spleen
Immunological
Haemopoeitic
Is the pancreas retroperitoneal
Yes, with the exception of it tail
Where does the tail of the pancreas lie
In the lienorenal ligament
Give two words to sum up the function of the pancreas
Endocrine and exocrine
What are the potential peritoneal spaces in the retroperitoneum
Subphrenic (Between the diaphragm and upper surface of the liver on either side of the falciform ligament) and the sub hepatic spaces (inferior to the liver)
How long is the duodenum
25cm
How is the duodenum divided
Superior (1st)
Descending (2nd)
Horizontal/ inferior (3rd)
Ascending (4th)
Describe the superior duodenum
5 cm long and the most mobile part
The first half is on the mesentery
Second half becomes retroperitoneal
Describe the descending duodenum
8 cm long descends to the right of the vertebral column and the inferior vena Cava
Overlies the hilum of the right kidney
The common opening of the bile and pancreatic duct into enters at the major duodenal papilla on the posteromedial wall
Describe the inferior duodenum
10 cm long passes from right to left across L3 over the inferior Vena cava and aorta
Crosses by the door of the small bowel mesentery within which lies the superior mesenteric vessels
Describe the ascending part of the duodenum
2.5 cm long S ends up on the left of
Psoas major to the side of L2
Turns forward at the duodenojejunal flexure
Partially retroperitoneal and partially on mesentery
Describe the arterial supply of the duodenum
Proximal to the entry of the bile duct the duodenum supplied by a branch of the coeliac trunk, the superior pancreaticoduodenal artery
Beyond this point into supplied by a branch of the superior mesenteric artery, the inferior pancreaticoduodenal artery
Here there is an anastomosis between fore and midgut
What is the largest gland in the body
How much does it weigh and how much blood does it receive Per minute
Liver
- 5kg
- 5L/min
How hard is a liver
In a cadaver it is firm and hard and but in life it is a red highly vascular and soft organ
What are the five ligaments of the liver
Falciform Right and left triangular Coronary ligament Ligamentum teres Ligamentum venosum
Describe the falciform ligament
A double peritoneal fold which is attached to the diaphragm and the anterior abdominal wall from the umbilicus
Where are the triangular ligaments
They run from the sides of the diaphragm to the posterior liver
Describe the coronary ligament
Continuous with the right triangular ligament and attaches the right lobe of the liver to the diaphragm
Describe ligamentum teres
The obliterated left umbilical vein which is contained within the free edge of the falciform ligament
Describe ligamentum venosum
Lies between the left and caudate lobe of the liver and contains the obliterated ductus venosus
What is the bare area of the liver
An area of the liver which is devoid of peritoneum
it lies against the diaphragm and posterior abdominal wall and is in contact with the inferior vena cava and right adrenal gland
How is the liver divided into right and left lobes
By the fissure fro ligamentum teres on the inferior surface and posteriorly by fissure for ligamentum venosum
What does the right lobe of the liver contain
How is it divided
Porta hepatis and fissure for IVC
Into the quadrate lobe and caudate lobe
Quadrate: between ligamentum teres and gallbladder
Caudate: between fissures for the IVC and ligamentum venosum
How is the caudate lobe connected to the right lobe
By the caudate process
Where does the fossa for the gallbladder lie in the liver
On the inferior surface of the right lobe
What are the relations of the lobes of the liver
Left lobe: oesophagus and stomach
Quadrate: pylorus
Right lobe: to the hepatic flexure and posteriorly to the right kidney
Caudate: to lesser sac
Where does porta hepatis lie
What is it
Between the quadrate and caudate lobes
The point of entry of the portal vein and hepatic artery as well as the exit of the left and right Hepatic ducts
Is the division of the liver into left and right lobe is important in practice
No it is mostly descriptive
Vascular input and bile output are in almost 2 equal halves with the quadrate lobe and most of the caudate lobe belonging functionally to the left half of the liver
What is on either side of the falciform ligament
Sub phrenic spaces
Should the liver be palpable in the adult
Is this the same for an infant
No the liver should not extend below the costal margin
if it is palpable the liver is enlarged
No, infants have relatively large livers compared the body size
How many can the right lobe ascend on expiration
4th costal margin (nipple level)
Why is the 4th costal margin only an anterior surface marking for the liver on expiration
The costodiaphragmatic recess extends inferiorly begins the liver
What are the 3 parts of the gallbladder
Neck
body
fundus
What is the surface marking of the fundus of the gallbladder
9th right costal cartilage
How many parts are there to the sphincter of Oddi
3:
Controlling common bile duct
Pancreatic duct
And the short segment after they have joined
Why may there be surgical complications when performing surgery around the gallbladder
There is considerable variation in the biliary tree
What does the hepatic portal system drain
Pancreas
Gallbladder
Spleen
GI tract from lower oesophageal sphincter to upper anal canal
The portal vein is formed by the union of which other veins?
Where Does this happen
Splenic and superior mesenteric veins
The inferior mesenteric vein joins at a variable distance along it
Anterior to right crus of diaphragm and IVC
Posterior to neck of pancreas at level of L1
What are sites of portosystemic anastomoses
When are these problematic
Areas where venous drainage can enter either the portal system or the systemic system
These areas do not usually cause problems but in presence of raised portal pressure, commonly due to liver disease from alcoholism, unmetabolised toxic substances can enter the systemic circulation and lead to clinical problems
What are the different parts of the pancreas
Where do the mesenteric arteries and veins lie
These don’t supply the pancreas
Head Uncinate process Neck Body Tail
Between the uncinate process and neck lie the superior mesenteric vessels with the vein on the right
The pancreas passes to the left. What does this mean
It crosses the left renal hilum and enters the lienorenal ligament
The tail lies within the lienorenal ligament and reaches the spleen’s hilum
How does the pancreas secrete digestive pro enzymes into the duodenum
Into the pancreatic duct duct which joins the common bile duct
What is the blood supply to the pancreas
Splenic and pancreaticoduodenal arteries
Give three things the spleen is related to
What does it lie against
Left kidney, tail of pancreas, gastric fundus.
It’s convex surface lies against the diaphragm, where it is related to the left ninth 10th and 11th ribs
How is the spleen connected to the abdominal wall and stomach
By peritoneal folds
Lienorenal ligament
Gastrosplenic ligament
What is the immunological function of the spleen
Producing and storing white blood cells particularly lymphocytes
It also destroys effete red blood cells
What is a common complication postsplenectomy
Liable to infection, especially of pneumococcal origin
What is the arterial supply to spleen
What is the venous drainage of the spleen
By a large splenic artery from the coeliac trunk
Its vein joins the superior mesenteric vein to form the portal vein
What pathology can occur at the duodenal flexion
Recesses may form into which internal herniation occur
Which part of the gastrointestinal tract is most likely to be damage in a car crash
The first part of the duodenum as it is most mobile
What can happen to the duodenal wall because of posterior peptic ulcers
What about anterior peptic ulcers
The wall can erode and the ulcers can penetrate the head of the pancreas where they may involve the gastroduodenal artery
Anterior ulcers may perforate into the greater sac of the peritoneal cavity
Define portal hypertension
Name a common cause
What does it result in
An increase in portal venous pressure
Alcoholic cirrhosis with fibrous tissue surrounding the intrahepatic vessels and biliary ducts
Impedes circulation of blood through the liver, forming portosystemic anastomoses
What is cholecystitis
What are the signs and symptoms
Inflammation of the gallbladder
Tenderness may be elicited when the patient inhales as descent of the diaphragm causes the liver and gallbladder to descend onto the examining head
How is a gallbladder usually removed
Laparoscopically
What does obstruction of the biliary tree result in
What does this lead to
Obstruction of which part of the biliary tree will not cause this?
Increased pressure within the system so that bile leaks from the liver into the general circulation
This leads to jaundice with a yellow staining of the skin and Sclera by biliary pigments
Cystic duct and gallbladder
What may cause obstruction of the biliary tree
Gall stones may cause intermittent jaundice
Tumours of the head of the pancreas may cause a painless obstructive jaundice that is continuous
Which is more painful gallstones or a pancreatic tumour? Both cause jaundice due to blockage of the biliary tree.
Gall stones
Fractures of which ribs may lead to a splenic rupture
Why is this bad
What is necessary if this occurs
9-11
The spleen is highly vascular and it will bleed into the peritoneal cavity
To remove the spleen -
however a splenectomy reduces immunological potential and increases the risk of overwhelming infection
preventative measures include prophylactic antibiotics
Discuss congenital abnormalities associated with the biliary tree
Lack of proper recanalisation of the small bowel or biliary ducts can lead to congenital narrowing or complete obstruction
This could lead to duodenal, ileal, and biliary atresia
What is a congenital condition associated with the pancreas
An Annular pancreas
Briefly how does the pancreas form in normal development
What about if an annular pancreas is formed
The head and neck of the pancreas are formed from left and right ventral buds which are fused together and rotate round as a single entity
If they do not confuse initially they may pass round opposite sides of the pancreas and then fused together does forming a ring of pancreatic tissue around the duodenum
What are the muscles of the posterior abdominal wall
Psoas major
Quadratus lumborum
Iliacus
What is each muscle of the posterior abdominal wall covered with
A dense and unyielding fascia to provide fixation for the peritoneum and retro peritoneal viscera
Where does the lumbar plexus form
Behind or with psoas major
Where does the abdominal aorta extend from
Then what happens to it
T12 to L4
It divides into the common iliac arteries
What are the branches of the abdominal aorta
Unpaired branches to the gut, paired branches to abdominal and pelvic viscera, and parietal branches to the abdominal wall
How does the inferior Vena Cava form and where does it extend from
The union of the common iliac veins
Extends from T5 to T8
What do the right adrenal, renal, and gonadal veins drain into?
What about on the left
On the right: directly into IVC
On the left: left adrenal and gonadal veins drain into the left renal vein
What are the kidneys embedded in
Perinephric fat which is contained within the renal fascia
Describe how the different adrenal glands relate to their kindey
The right adrenal embraces The upper pole of the right kidney.
The left adrenal embraces the medial border of the left kidney above the hilum
Both relate posteriorly to the diaphragm
What are the ureters in line with
The tips of the lumbar transverse processes and sacroiliac joint
What are the three sites of relative narrowing of the ureters
The pelvi-ureteric junction
Pelvic brim
Point of entry into the bladder
What does the diaphragm arise from
The upper three lumbar vertebral bodies, the arcuate ligaments on the posterior abdominal wall, the lower six ribs, and xiphisternum
What is the origin of psoas major
Innervation?
5 lumbar vertebrae, their intervening discs and transverse processes
Segmental (L1-3)
What is the course of psoas major
Arises from 5 lumbar vertebrae
Passes inferiorly, medial to the iliac bone, where it joins iliacus to form iliopsoas tendon
It is now supplied by the femoral nerve
This tendon inserts the lesser trochanter of the femur
What is the action of iliopsoas/ psoas major
Flexor of hip joint and trunk
Describe the course of quadratus lumborum
Runs between posterior part of the iliac crest, the 12th rib and the lumbar transverse processes
What is the function of quadratus lumborum
Innervation?
Stabilises the vertebral column and fixes the twelfth rib for diaphragmatic movements
Supplies by anterior rami of T12-L4
What are the medial and lateral arcuate ligaments
The thick and upper borders of the psoas major and quadratus lumborum fascia respectively
What do the anterior rami of the upper 4 lumbar spinal nerves form
Which nerve passes nearby but is not part of the plexus
The lumbar plexus
T12 (subcostal nerve)
What are the main branches of the lumbar plexus
Iliohypogastric (L1, main nerve) and ilioinguinal (L1, collateral branch)
Genitofemoral (L1,2)
Lateral femoral cutaneous branch (L2,3)
Femoral (L2-4 posterior divisions)
Describe the course of the iliohypogastric and ilioinguinal nerves
From anterior rami of L1 in lumbar plexus
Pass between transversus abdominis and internal oblique
Ilioinguinal runs in inguinal canal and is mostly sensory
The genitofemoral nerve divides into which nerves
What is the spinal nerve root associated
What does each supply
Femoral branch (L1) - supplies skin over upper anterior thigh
Genital branch (L2) - runs in inguinal canal to supply contents of spermatic cord and the cremasteric muscles
Describe the course of the lateral femoral cutaneous nerve
Passes across iliacus and enters thigh beneath the lateral part of the inguinal ligament medial to the anterior superior iliac spine
Describe the course of the femoral nerve
From the posterior divisions of L2,3,4 it passes into the anterior thigh and supplies the quadriceps muscle, Sartorius and pectineus and the skin on the thigh
What supplies the skin on the medial aspect of the thigh
Give associated nerve root
Obturator nerve (L2-4)
Most of L4 contributes to the lumbar plexus. What happens to the rest of it
Joined L5 to form that lumbosacral trunk
What are the four groups of branches of the abdominal aorta
Inferior phrenic arteries
the three anterior unpaired visceral branches to the gastrointestinal tract
three lateral paired visceral branches
four pairs of lumbar arteries and the median sacral artery
Which arteries to the inferior phrenic arteries give
The superior adrenal arteries
What are the three anterior unpaired visceral branches of the abdominal aorta to the gastrointestinal tract
The coeliac trunk, the superior and inferior mesenteric arteries
What are the three lateral paired visceral branches of the abdominal aorta
The renal arteries, the middle adrenal arteries, and the gonadal arteries
Which arteries give the inferior adrenal arteries
The renal arteries
Which lymph nodes receive lymph from the gastrointestinal tract
Pre aortic nodes
The para aortic nodes receive lymph from where
Non alimentary viscera and the lower limbs
In the abdomen is the sympathetic chain in front of or behind the IVC
It is behind the IVC on the right
The femoral artery is an extension of which artery
The external iliac artery
Describe the course of the IVC in the abdomen up to the heart
It is formed by the union of the common iliac vein is to the right of L5. It passes on the right of the abdominal aorta to the liver where it lies in a groove and receives the hepatic veins. It passes through the central tendon of the diaphragm at the level of T8 and opens into the right atrium
Where does the IVC pass through the diaphragm
Through the central tendon at T8
True or false: the right renal vein is much shorter than the left
True
The IVC lies to the right of the midline
Where does the left renal vein cross the aorta
Just below the origin of the superior mesenteric artery
What do the upper two lumbar veins drain into
They come together to form the azygous vein on the right and the hemiazygous Vein on the left
True or false venous drainage from the gastrointestinal tract is to the IVC
False it is to the portal vein
What level are the kidney’s hila
L1
Which kidney is lower and why
The right kidney is lower due to the liver
Which direction do the hila of the kidneys face
Anteromedially
What are the tributaries in each Renal hila from anterior to posterior
Renal vein, renal artery, renal pelvis
Name one hormone the kidney producers
What is it function
Renin
Control of blood pressure
Are the adrenal glands within the renal capsules
No
Which adrenal is related to the bare area of the liver and the inferior vena cava
Right
How many arteries supply the adrenals
How many veins
3
1
How long are the ureters
What do they lie anterior to
25 cm
Genitofemoral nerves and the bifurcation of the common iliac artery
On the left where does the ureter enter the pelvis
At the apex of the sigmoid mesocolon
How do ureters travel in the pelvis
From the ischial spines, they continue anteromedially along the pelvic floor to enter the base of the bladder
How is ureteric pain felt
Sequentially: first in the line, then in the iliac fossa, and finally in the penis
What are the origins of the posterior fibres of the diaphragm
Right and left crura from the upper lumbar vertebra, L3- L1 on the right and L1 and L2 on the left;
medial and lateral arcuate ligaments
What are the origins of the lateral fibres of the diaphragm
Inner surfaces of the lower six costal cartilages, interdigitating with the transversus abdominis muscle
What is the origin of the anterior fibres of the diaphragm
Small slips from the back of the xiphisternum
Where do all muscle fibres in the diaphragm insert
Into a central tendon which is a trilobed structure fused with the fibrous pericardium
What does the diaphragm look like a) in sagittal section and B) in coronal section
a) inverted J with the long limb running up from T12
b) fibres slope up and medially into 2 dimes which descend towards the central tendon
What are the surface markings of the right dome, left dome, central tendon, of the diaphragm in full expiration
Right: 4th intercostal space
Left: 5th rib
Central: 6th costal cartilage (end of sternum)
What are the three main levels that structures are passed through the diaphragm between the thorax and abdomen
T8.
T10
T12
Which structure is passed through the diaphragm at T8
IVC, right phrenic nerve
Which structures pass through the diaphragm at T 10
Oesophagus with vagal trunks, branches of left gastric vessels
Which structures passed through the diaphragm at T 12
Aorta
Azygous vein
Thoracic duct
Other than the vagi, discuss nerves passing through the diaphragm
Sympathetic trunks pass posterior to the medial arcuate ligament.
Splanchnic nerves pierce the crura;
left phrenic nerve pierces the left dome
T7 to T 11 intercostal nerves pass between the digitations of the diaphragm
subcostal neurovascular bundle is passed posterior to the lateral arcuate ligament
What are the terminal branches of the internal thoracic artery
Do they pass through the diaphragm
Musculophrenic
Superior epigastric
Yes
WhatCarries sympathetic innovation to the abdomen
What happens when they enter the abdomen
The greater, Lesser, and least splanchnic nerves
Converge to form the coeliac plexus
What forms each of the splanchnic nerves
Greater: T5-9 ganglia
Lesser: T10-11 ganglia
Least: 12th thoracic ganglia
What is the only structure in the abdomen that receives preganglionic sympathetic fibres
Which fibres are these and what is their course
Adrenal medulla
Arise largely from T10, pass with the splanchnic nerves and then via the coeliac plexus to the adrenal medulla
How is adrenaline released near the effector organ
As a hormone not a neurotransmitter
Which spinal segments are parasympathetic
S2-4
How do parasympathetic fibres supply the hindgut
They extend from the pelvis to reach the inferior mesenteric plexus for distribution to the descending colon and distal third of the transverse colon
What is the largest prevertebral plexus
Give a brief description
The coeliac plexus, surrounding the origin of the coeliac trunk
It contains several ganglia and gives branches which accompany the blood vessels to the viscera and form a secondary plexuses at these arteries
How can the remaining practices i.e. not including the coeliac plexus be considered
As extensions of the coeliac plexus
Other than the coeliac plexus, name three autonomic plexuses in the abdomen
Hepatic, splenic, Renal
Which practices supply the foregut, midgut, and hindgut structures respectively
Fore: coeliac
Mid: superior mesenteric
Hind: inferior mesenteric
Describe the course of the pre-aortic plexus
It continues pass the aortic bifurcation and coalesces as a single superior hypogastric plexus, which descends into the pelvis to become the left and right inferior hypogastric plexuses
What is an abdominal aortic aneurysm
What is it a result of
A localised dilation of the abdominal aorta
resulting from a weakness of the aortic wall
Where do abdominal aortic aneurysms usually arise
Usually Below the kidneys but may also be above or at the level of the kidneys
Can an abdominal aortic aneurysm affect the common iliac arteries
Yes and aneurysm may also extend to include one or both of the common iliac arteries
Which kind of patients are most likely to get an abdominal aortic aneurysm
Male smokers
When would surgical repair be performed for an abdominal aortic aneurysm
If symptomatic or if >5.5cm in diameter
Severe pain in the abdomen and back is a characteristic of what
What does this lead to if unrecognised
Acute rupture of an abdominal aortic aneurysm
Severe blood loss meaning the mortality rate will be high
What is at risk of being torn during surgery on the right kidney
The short renal vein
What is a varicocele
What can a left sided varicocele indicate
A scrotal swelling caused by dilated veins
This may be a result of a left renal cell carcinoma as these may extend along the left renal vein and obstruct the left testicular vein which drains into it
Radiotherapy of which lymph-node’s may be necessary in testicular cancer
Para aortic nodes
Which nerve may be injured during open repair of an inguinal hernia
Ilioinguinal
What may laparoscopic inguinal hernia repair result in
Tack Entrapment of the ilioinguinal nerve
What is meralgia paraesthetica
What are common causes
Entrapment of the lateral femoral cutaneous nerve as it passes through or below the inguinal ligament, leading to numbness or pain in the outer aspect of the thigh
Restrictive clothing and weight gain
What is a calculus
A stone
What may lead to referred pain in the lime, iliac fossa, and the penis
Ureteric colic due to passage of a stone down the ureter
How can you tell at operation if something is a ureter
If lightly pinched, the year it is Will contract
Name one kidney developmental abnormality and one ureteric
Renal cystic disease
Ureteric duplications
What may cause a horseshoe kidney to form
What else can be caused by this
Defective Ascension or fusion of the metanephros
A pelvic kidney which people
What causes a congenital diaphragmatic hernia
A Phalia of fusion of the various elements that form the diaphragm, with herniation of abdominal contents into the thorax
