Abdominal + Pelvis Anatomy & Imaging Flashcards
How many regions make up the Abdominal section of the body?
9 Regions:
Right Hypochondriac , Epigastric, Left Hypochondriac
Right Lumbar, Umbilical, Left Lumbar
Right Inguinal, hypogastric, Left Inguinal
What are the lines that seperate the abdomen?
Transpyloric Line: Pylorus, Curve of duodenum, Hilum of kidney.
Transtubercular Plane:
Mid Clavicular Lines (vertical)
Is the stomach free moving and if so clinically where would it be?
Stomach is VERY MOVEABLE
In skinnier/ tall people stomach is further down near Hypogastric region
In Larger/ obese people stomach is further up into the epigastric region
What is the small intestine held by and does it move?
Small intestine is very moveable and is held by the mesentery
Where are the liver and the spleen located?
Below the costal margin
Describe how the liver and spleen would move if enlarged?
Would DESCEND below the costal margin
What kind of structures are fixed
Give an examples.
RETROPERITONEAL STRUCTURES!
Duodenum, Pancreas, Kidneys, Ascending and Descending colon
Describe the layering of Superficial Fascia :
Below the UMBILICUS there are TWO LAYERS
- Campers Fascia: Is the fatty layer of superficial fascia
- Scarpers Fascia : Deep Membranous layer
Describe the organisation of Scarpas Fascia
“Swimming Trunks” Organisation
Will attach just below umbilicus, keep going around the scrotum and the shaft of penis until the GLANS.
Will keep going into the perineal Body
Describe the attachment points of Scarpas Fascia:
Anteriorly: Passes over anterior abdominal wall
Inferiorly: Passes into the scrotum
Laterally: Attached to ischiopubic ramus
Posteriorly: Attached to perineal membrane (NOT ANAL TRIANGLE)
Describe the flow of blood due to internal bleeding in Scarpas fascia:
Confined to the region BELOW SCARPAS
A rupture of the spongy urethra would see urine track where?
URINE EXTRAVASATION
Will track into the scrotum and anterior abdominal wall.
Identify this muscle and its attachments
Rectus Abdominis
Origin: Costal Cartilage of ribs 5-7
Insertion: Pubic Crest
Major Flexor of the abdomen
What is the midline of the abdomen and Rectus abdominus called and when stretched what does it produce?
Linea Alba
When stretched can produce Rectus diastasis
What is the muscle and its attachments?
External Oblique Muscle
Origin: Lower 8 Ribs
Insertion: Posterior fibres pass vertically to illiac crest
Rest passes to illiac then ASIS
Aponeurosis passes from ASIS to pubic tubercle
Rotate the trunk , Flexion and lateral flexion
What forms the Inguinal Ligament?
The lower tendon of the aponeurosis will fold under itself to form the Inguinal ligament
What are the gaps in the EXTERNAL OBLIQUE and what is the clinical significance?
Sites of HERNIA (Organ protrusion)
Lumbar Triangles (posterior)
Superficial Inguinal Ring
Midline Linea Alba
Label
What are the Lumbar triangles and where are they located?
Superior Lumbar Triangle:
Base: 12th Rib
Medially: Quadratus Lumborum
Laterally: Internal Oblique
SITE OF MOST COMMON HERNIATION
Inferior Lumbar Triangle:
Medial : Latissimus Dorsi
Lateral: External Oblique
Inferior Border: Illiac Crest
An increase in abdominal pressure can do what?
Bulge Linea alba anteriorly:
RECTUS DIASTISIS
label the muscle, origin, insertion as well as what the movement is
INTERNAL ABDOMINAL OBLIQUE
Origin: Thoracolumbar Fascia, Illiac crest and ASIS, Lateral 2/3 of Inguinal Ligament
Lowest fibres will attach to pubic tubercle and contribute to Inguinal ligament
Insertion: Mostly joins with EXT OBLIQUE to form Rectus sheath
Minority of fibres will attach to lower 4 ribs
WORKS IN TANDEM WITH OPPOSITE EXTERNAL OBLIQUE MUSCLE. Eg. Left Shoulder to left hip = Left external oblique and +Right internal oblique
What is deep to the internal oblique muscle which has belt like fibres ? Name origin, insertion and movement
Transversus Abdomonis
Origin: Thoracolumbar fascia, Illiac Crest, Last 6 ribs, lateral 3rd of Inguinal ligament.
Insertion: Most of the muscle inserts into Rectus sheath,
Minority will insert into pubic tubercle and pectineal line as part of conjoint tendon.
PULLS ABDOMEN INWARDS during contractions, Major muscle for spine support. (Why a wide belt is used when deadlifting)
What is the nerve supply of the Abdominal Mucles?
T6 - L1 Ventral Rami
Lie between internal oblique and Transversus abdominis
Will supply the muscle and skin segmentally but with some overlap.
What are the continuations of the abdominal Ventral Rami ?
INTERCOSTAL NERVES
SUBCOSTAL NERVE - T12
ILLIOHYPOGASTRIC + ILLIOINGUINAL - L1
What are the muscles responsible for left trunk rotation?
Left ext oblique
Right int oblique
What are the muscles responsible for Trunk Flexion?
Rectus Abdomonis
What are the muscles responsible for Left Lateral Flexion?
ALL LEFT LATERAL MUSCLES
What are the muscles responsible for Pulling anterior abdominal wall in “Bracing”.
Transversus Abdomonis
When will the concept of “guarding” occur clinically?
Contraction of abdominal muscles - rigid abdomen occurs due to abdominal visceral problem of irritation of the peritoneum.
Outline the cause of Meralgia Parasthetica:
Compression of the lateral cutaneous nerve (Branch of Lumbar Plexus)
Common in pregnancy and obesity:
Paralysis of the the lateral aspect of thigh.
Identify the main supplying arteries of the Abdomen and their origins:
- Subcostal and Lumbar arteries
Thoracic aorta origin , Supply posterior lateral aspect of trunk - Superior Epigastric: Continuation of the internal thoracic which runs deep to Rectus Abdomonis
- Inferior Epigastric : Off External Iliac Artery [+DEEP CIRCUMFLEX ILLIAC], RUNS DEEP TO RECTUS ABDOMONIS
- Superficial Inferior epigastric artery (above muscle and deep to skin)
- Superficial circumflex illiac + Superficial inf epigastric -> COMES OF FEMORAL ARTERY -> travels more laterally.
Label
What is the main drainage of the abdomen?
Subclavian or femoral Vein
Label the veins:
UP TO DOWN LABELLED
Lateral thoracic
Thoracoepigastric
Paraumbilical
Superficial Epigastric
Superficial Circumflex Iliac
Superficial Epigastric
Femoral
Describe Caput Medusa
what is the connection with portal hypertension?
Enlargement of the paraumbilical veins due to occluded veins somewhere else.
Eg: Blocked veins in the liver force blood back into the paraumbilical veins
PORTAL HYPERTENSION
Describe the issue and what is happening to the blood
OCCLUDED IVC
Blood is flowing back into the femoral and into the paraumbilical which is travelling superiority into the thoracoepigastric vein.
Describe the issue and what is happening to the blood
OCCLUDED IVC
Blood is flowing back into the femoral and into the paraumbilical which is travelling superiority into the thoracoepigastric vein.
What is the lane halfway between the costal margin and the umbilicus called AND WHAT IS ITS SIGNIFICANCE
Watershed!
- Lymph above will drain superiorily to axillary lymph nodes and the thoracic duct
Lymph below will drain inferiorly to Inguinal lymph nodes.
Therefore lymph nodes that would drain the region is what would enlarge during infection.
Label the lymph nodes
What will the Inguinal canal transmit for males and females?
Spermatic chord for males and ROUND LIGAMENT for females.
Smaller structure in females due to small size of round lig (roughly 1 mm in diameter) therefore not likely to develop herniation
Male structures are larger and could herniate
Label The layers of the Inguinal canal
What are the walls of the Inguinal Canal?
Anterior: Ext Oblique Aponeurosis
Floor: Inguinal Ligament : Folding of ^^^^
Roof: Int Oblique and Transversus Abdomonis
Posterior: Transversalis Fascia and peritoneum.
What are the two types of Inguinal hernia?
A direct Inguinal hernia travels directly to the surface via the Inguinal canal. Eg: Intestine pushes on abdominal wall.
IS MEDIAL TO THE INFERIOR EPIGASTRIC VESSELS
An indirect Inguinal hernia travels indirectly through the abdomen layers via the deep Inguinal ring.
FOUND LATERAL TO INFERIOR EPIGASTRIC VESSELS.
What makes up the Foregut:
Oesophagus, Stomach, Liver, Gallbladder, Bile ducts, pancreas, proximal duodenum
What is the blood supply of the foregut?
Coeliac trunk and veins named after organs
What is the nerve supply of the foregut?
Coeliac Plexus (T5-9 plus VAGUS X)
What are the lymph nodes which drain the foregut
Coeliac lymph nodes
Referred pain the foregut is also known as
EPIGASTRIUM
What composes the midgut
Distal duodenum, Jejunum, Ileum, caecum , appendix, ascending colon and first 2/3 of transverse colon.
What is the blood supply of the midgut?
Superior mesenteric artery and vein
What is the nerve supply of the midgut?
Superior Mesenteric Plexus (T10 T11 + VAGUS X)
Pain in the midgut is referred to as
UMBILICAL
Pain in the midgut is referred to as
UMBILICAL
What drains the lymph from the midgut?
Superior mesenteric lymph nodes
What composes the hindgut
Last 1/3 of transverse colon, descending and sigmoid colon, rectum and upper 2/3 of anal canal.
What is the blood supply of the hind gut?
Inferior Mesenteric Artery and vein
What is the nerve supply of the hindgut?
Inferior Mesenteric plexus (L1 L2 and S2-S4)
Where will lymph drain from the hindgut?
Inferior mesenteric lymph nodes
Pain is reffered to as _____ in the hindgut
Suprapubic
Where is the oesophagus relative to the trachea?
Posterior
What are the 3 parts of the oesophagus?
Cervical -> (Inf Thyroid artery and Veins)
Thoracic -> (Thoracic Aorta and azygous vein)
Abdominal -> (Left Gastric Artery and vein )
What are the 3 constrictions of the oesophagus?
Cricopharyngeal Sphincter
Aortic arch (+left main bronchus)
Diaphragm (Right Crus)
What are the 3 constrictions of the oesophagus?
Cricopharyngeal Sphincter
Aortic arch (+left main bronchus)
Diaphragm (Right Crus)
An impression is left on the oesophagus by the ______
LEFT ATRIUM OF THE HEART
During motor neurone disease, what muscle is cut to facilitate swallowing.
CRICOPHARYNGEUS muscle:
Does not require force to push bolus through.
.
What is an Osophageal Stricture?
Constriction of the oesophagus:
Due do ingestion of bleach or acid or external damage.
In the following image describe what is occurring
The small portion of the stomach is exiting the Esophogeal hiatus and creating a HIATUS HERNIA
Describe Barrett’s Oesophagus:
When the right crus of diaphragm is not predominant, gastric juice can leak into the oesophagus. Acid can break down the columnar epithelium which lines the abdominal oesophagus. Tissue will try to mitigate but could lead to become cancerous.
Describe Barrett’s Oesophagus:
When the right crus of diaphragm is not predominant, gastric juice can leak into the oesophagus. Acid can break down the columnar epithelium which lines the abdominal oesophagus. Tissue will try to mitigate but could lead to become cancerous.
Where is the stomach normally located?
Mostly in the epigastric region
Where is the stomach normally located?
Mostly in the epigastric region
Describe how the stomach is held in the epigastric region:
Suspended via the liver by the lesser omentum (Hepatoduodenal and hepatogastric ligament )
Greater omentum attaches to the greater curvature of the stomach .
Describe how the Greater and lesser sac are formed in relation to the greater and lesser omentum
Liver attatches to stomach via lesser omentum
Greater omentum will project inferiorly and reflect back up to encroach the transverse colon to the posterior abdominal wall (TRANSVERSE MESOCOLON)
The greater sac is everything external relative to lesser omentum .
How do the greater and lesser sac communicate?
Via the EPIPLOIC FORAMEN
Right free border of Lesser omentum
Epliploic foramen contains what vessels?
The hepatic artery proper, portal vein and common bile duct
(Can be compressed)
What are the 4 main regions of the stomach?
Fundus
Body
Pylorus
Cardia
What supplies the stomach and what are the arteries that contribute to this?
Coeliac Trunk:
Three main branches
Left Gastric A
Splenic A
Common Hepatic Artery (Liver and small parts of intestine.
What artery lies along the lesser curvature of the stomach?
Left Gastric Artery
What will the left gastric artery anastomose with ?
hepatic artery
What are the branches of Common hepatic artery
Hepatic Artery +Gastroduodenal Artery
What artery passes POSTERIOR to the duodenum
Gastroduodenal artery
An ulcer at the duodenum may perforate and cause damage to the __________
Gastroduodenal artery
What does the Gastroduodenal artery anastomose with after covering the greater curvature of stomach?
Splenic artery:
Will form gastroepiploic arteries
Involving the arteries of the stomach, explain a method of treatment for obesity:
The left gastric artery can be embolised as a treatment for obesity which causes moderate ischamia of the fundus and therefore subsequent reduction in serum ghrelin secretion.
Where are stomach ulcers normally found?
Found along the lesser curvature
Describe the venous drainage of the stomach:
Portal Vein system:
Composes of Left and right Gastric veins
Pancreaticduodenal vein
Splenic vein
Right and left gastroepiploic veins ANASTAMOSE WITH SPLENIC
Superior mesenteric (Continuation of portal)
Inferior Mesenteric (splenic)
What is the lower 1/3 of the oesophagus venuous drainage
SHARED DRAINAGE
Left gastric vein for portal system
Azygous vein for systemic system
Shared porto-systemic anastomose
Due to blood not flowing though the liver properly (cirrhosis) or portal hypertension, what will occur.
Back pressure located in the lower oesophageal region causing vein dilation.
LIFE THREATENING
What makes up the stomach bed and what can occur if there is a posterior perforating stomach ulcer:
Pancreas, left kidney, spleen , splenic vessels.
