Discuss the embryology of the diaphram
Formed from septum transversum myotomes C3-C5 contributions from body wall and dorsal mesentery
Describe attachments of the diaphram
Peripheral : Xiphoid process, lower 6 ribs, arcuate ligaments, and cruraeCentral : fibrous tissue surrounding the heart
Describe the shape of the diaphram
Two domes Ascend as high as 5th rib Right is higher than the left (due to liver)
Discuss the functions of diaphram:
Separates abdominal cavity from thoracic cavity Breathing : contraction of diaphram pulls central tendon inferiorly; flattens domes; increases thoracic capacity; lower intra-thoracic pressure; draws air into lungsPump : pumps venous blood up from below; same reason aboveAbdominal straining : helps micturition, defecation, parturitionWeight lifting
Describe the median arcuate ligament
Made of the medial borders of the crurae Surrounds aorta
Discuss the arcuate ligaments
Median arcuate ligament : arches over aortaPair of lateral arcuates : arch over quadratus lumborumPair of medial arcuates : arch over psoas
What is the blood supply to the diaphram?
Blood supply is from superior and inferior phrenic arteries (from aorta) Musculophrenic and pericardiophrenic arteries (from internal thoracic arteries)
State the structures passing through the oesophageal opening
Oesophagus Left and right vagus nerves
Name structures that pass through the aortic hiatus
Aorta Azygos vein Hemiazygos vein Thoracic duct
Describe lymph drainage of the diaphram
Celiac superior mesenteric nodes Common iliac nodes
True or false? The liver forms from the ventral mesenteryTrue False
True!
True or false? The spleen forms from the ventral mesentaryTrue False
False! It forms from the dorsal mesentary
What is lesser omentum?
A bit of visceral peritoneum that runs from the lesser curvature of stomach to liver
What and where is the epiploic foramen?
It’s a passageway between the greater sac and lesser sac Located in the right free edge of the lesser omentum
Describe the margins of the epipploic foramen
Anteriorly : Free edge of lesser omentum, which contains the Bile duct (right), Hepatic artery (left), Portal vein (behind and between them).Posteriorly : Inferior vena cavaSuperiorly : Caudate lobe of liverInferiorly : 1st part of duodenum
Discuss the porta hepatis
Structures passing to the liver Hepatic artery, portal vein, autonomic fibers Structures passing out Right and left hepatic ducts Lymphatics
What is the ampulla of Vater?
Short duct which drains the bile duct and main pancreatic duct
What is the sphincter of Oddi?
It’s a sphincter around the distal bile duct, main pancreatic duct, and ampulla of Vater
Name 4 major vessels of the abdomen
Abdominal aorta Inferior vena cava Azygos vein Hemiazygos veins
Describe the abdominal aorta
Enters the aortic hiatus at T12 Runs in front and to the left of Lumbar vertebrae Splits into common ilac arteries at L4 Can be palpate just above umbilicus
Describe the branches of Abdominal aorta!
Ventral -- Celiac trunk -- SMA -- IMA Lateral -- Inferior phrenic -- Middle Suprarenal -- Renal -- Testicular OR ovarian Dorsal -- Lumbar -- Median Sacral Terminal branches -- Common iliacs
Describe the Inferior vena cava
Formed from union of common iliacs at L5 Passes upwards on the right side of Aorta Goes through central tendon of diaphram at T8
Name the tributaries of the IVC
Common iliacs (the left one recievs the median sacral) Third and fourth lumbar (1st and 2nd enter the 3rd) Right gonadal vein (left drains into left Renal vein) Renal veins Right supra renal (left drains into left Renal) Hepatic veins
Discuss clinical significance of azygose and hemiazygos veins
In blockage of IVC (like thrombosis) a connection is made between the IVC and SVC via these veins.
Describe the Psoas muscle
Type : fusiformOrigins : lumbar vertebraeCourse : goes behind ingunal ligament and infront of hip jointInsertion : lesser trochanterAction : flexes trunk anteriorly and laterally, flexes hip and medially rotates hipNerve supply : lumbar plexus
Describe the Illiacus
Shape : fan-shapedOrigin : ilac fossaInsertion : Lesser trochanter Innervation : femoral nerve (L2, L3)Action : flexes hip
Describe the Quadratus Lumborum
Type : strapOrigin : 12th ribInsertion : ilac crest Innervation : Lumbar plexusAction : laterally flexes trunk
Description of branches of the sacral plexus + details of Femoral and Obturator arteries
L1 -- Iliohypogastric -- Ilioinguinal L1, L2 -- Genitofemoral L2, L3 -- Lateral cutaneous nerve of thigh L2, L3, L4 -- Femoral nerve ---- Emerges from lateral side of psoas, goes beneath inguinal ligament, into thigh, divides into: ------ anterior : supplies skin over anterior thigh------ posterior : supply hip and knee joint, quadriceps, gives rise to:-------- saphenous nerve : supplies skin on medial side of leg and foot -- Obturator nerve ---- Emerges from medial side of psoas, passes in front of sacro-iliac joint, through obturator canal, divides into: ------ anterior and posterior : supplies adductors + supplies skin on medial thigh, hip, and knee joint
