Exam IV: Abdomen IV Flashcards Preview

Anatomy > Exam IV: Abdomen IV > Flashcards

Flashcards in Exam IV: Abdomen IV Deck (27):

Psoas Major

Lateral surface of T12 and L1 to L5 vertebral bodies
Transverse process of lumbar vertebrae
Intervertebral disks between T12 and L1 to L5
Lesser trochanter of femur (underneath the inguinal ligament)

Innervation: anterior rami of L1 to L3

Functions: flexion of thigh at hip joint


Psoas Minor

Lateral surface of T12 to L1 vertebrae and intervertebral disk
Pectineal line of the pelvic brim
Iliopubic eminence

Innervation: anterior rami of L1

Functions: weak flexion of lumbar vertebral column

It passes anteriorly on top of the psoas major


Quadratus Lumborum

Transverse process of L5 vertebrae
Iliolumbar ligament comes across the iliac crest and attaches to it, and to the inferior border of rib 12
Transverse process of L1 to L4 vertebrae

Innervation: anterior rami of T12 and L1 to L4

Functions: depress and stabilize rib 12 with some lateral bending of trunk



Upper 2/3 of iliac fossa
Anterior sacro-iliac
Iliolumbar ligaments
Upper lateral surface of sacrum
Similar to psoas major- passes over inguinal ligament to lesser trochanter of femur

Innervation: femoral nerve (L2 – L4)

Functions: flexion of thigh at hip joint


Musculature: Diaphragm Parts and Ligaments

1. Sternal head – xiphoid process → central tendon
2. Costal – costal cartilage 7-12 → central tendon
3. Lumbar – lumbar vertebrae 2 and 3 → central tendon
Right crus- attaches to L2 and L3; much larger and comes over the hiatus for aorta goes up to loop over the esophageal hiatus and then comes back down
Left crus- attaches to L2

1. Medium arcuate: goes over aorta
2. Medial arcuate: psoas major
3. Lateral arcuate: quadratus laborum; hopping from transverse process to rib 12


Diaphragm: Esophageal and Aortic Hiatus & Vena Caval Foramen

Vena caval foramen: contain IVC, right phrenic nerve at level T8; need to get blood from liver back to the heart; left phrenic nerve does not have a specific opening, but still goes through diaphragm

Esophageal hiatus: contains esophagus and right and left vagal trunks, esophageal artery from left gastric artery at level T10

Aortic hiatus: contains aorta, thoracic duct, azygos vein at level – T12
Sometimes the azygos vein goes through the right crus and hemiazygos goes through left crus


Diaphragm: Splanchnic Nerves, Azygos System, Sympathetic Chain, and Superior Epigastric

Greater, lesser and least splanchnic: pass through the crura

Azygous and Hemiazygous: pass through the crura

Sympathetic trunks: pass through medial arcuate ligament and psoas

Superior epigastric: pass anterior to diaphragm


Diaphragm: Blood Supply and Innervation

Blood supply:
1. Superior: internal thoracic artery divides into musclophrenic and superior epigastric; pericardiophrenic comes off internal thoracic alongside the heart with the phrenic nerve; aorta, and superior phrenic artery
2. Inferior: abdominal aorta and inferior phrenic artery

Innervation: C3, 4, and 5 "keeps you alive"
Motor and sensory to central part
Intercostal nerves
Sensory on peripheral areas

Question: cardiothoracic surgery, open pericardium, periocardial phrenic arteries cut on accident, pick another artery that supplies the diaphragm as well (antastomoses with phrenic)= superior phrenic artery


Domes of the Diaphragm

Right side ~ rib V
Liver- pushes diaphragm upwards
Right kidney
Right suprarenal gland

Left side ~ 5th intercostal space between ribs 5 and 6
Left kidney
Left suprarenal gland


Location of Kidneys

Right KidneyDescending part of duodenum sits over right hilum, right colic flexure on top, and small intestine, liver
Left Kidney: stomach at superior border, spleen on superior border, pancreas coming apart (when we take off pancreas we take off peritoneum because kidney is retroperitoneal as well), stomach

If someone is having a GI scope, what if we rupture the colon, we need to be aware of the kidney and make sure we don’t damage that too
Posterior wall of left splenic flexure cut on accident: kidney could be damage-QUESTION


Posterior View of Kidneys

Posterior view: kidneys are somewhat well protected because ribs are only covering the kidneys somewhat= ribs 11 and 12

Muscles of deep back (psoas, quadratus luborum, and transversus abdominus)

Why aren’t the kidneys at the same level: during development kidneys start in pelvic and then need to ascend; Left side moves first and right moves up next and they stop at the same time

Horseshoe kidney where it sits on lower abdomen because gets stuck


Secondary Support of Kidneys: Fascia and Fat

Renal fat and fascia- secondary protection of kidneys
Perirenal fat (perinephric fat)- innermost layer
Renal fascia- middle layer
Pararenal fat (paranephric fat)- outermost layer

Both fatty layers + fascia = ½ inch in width to provide support


Kidney Structures

1. Hilum of kidney where blood flow comes in and renal pelvis comes out
2. Outside = cortex
3. Inner layer = renal medulla with columns (lighter areas) and the pyramids (triangles)
4. Renal Papilla: where pyramid and minor calyx meet

Urine passes into the minor calyx, 2-3 minor calyxes come together to make major calyx, then urine goes to pelvis through the ureters to bladder


Renal Vasculature and Lymphatics

Renal artery- width of pinky because it filters ALL blood; comes directly from the aorta to the renal arteries
Renal veins- brings blood to the IVC
Lateral aortic (lumbar) nodes: on both sides of vertebral column that drain lymphatics

Superior mesenteric pass on top of left renal vein (makes a sandwich)
Say aortic ayneurysm- apply pressure to left renal vein… want good blood flow to kidneys, but this would impede it



Points of constriction:
1. ureteropelvic junction
2. pelvic inlet: ureter passes through abdomen, bifurcation at L4
3. entrance to the bladder
causes a chain reaction of problems, but prevent stones from coming through

Ureteric vasculature: renal arteries, aorta, testicular/ ovarian, common iliac, and internal iliac

Ureteric and lymphatics: lateral aortic (lumbar)nodes, common iliac, external and internal iliac; wherever it got blood supply from lymph will go back there

Ureteric innervation: parasympathetic and sympathetic innervation because hollow organ it will get autonomics


Suprarenal Glands

Endocrine glands sit on top of kidneys, and get lots of blood coming in and out of the glands

1. Inferior phrenic (from aorta): superior suprarenal arteries
2. Aorta: middle suprarenal arteries; direct blood supply
3. Renal artery: inferior suprarenal arteries



Visceral branches:
Celiac trunk
Superior mesenteric
Inferior mesenteric
Middle suprarenal arteries
Renal arteries
Testicular/ovarian arteries

Posterior branches:
Inferior phrenic arteries
Lumbar arteries
Median sacral artery
Common iliac arteries- bifurcation at L4 into external and internal branches on each side


Inferior Vena Cava (IVC)

As we pass lower, we have kidney and IVC receiving renal blood
Duodenum, pancreas= over lining IVC
If giving upper scope and perforate at 1st segment of duodenum posterior then hurt IVC


Inferior Vena Cava Drainage System

Receive blood from:
Common iliac veins
Lumbar veins
Right testicular or ovarian vein
Renal vein
Right suprarenal vein
Inferior phrenic veins
Hepatic veins

Lumbar veins
5th lumbar veins → iliolumbar vein
1st and 2nd lumbar veins → ascending lumbar veins → azygos and hemi-azygos veins

IVC problem from damage/blockage- great alternative pathway is hemiazygos /azygos because they all go to azygos system to the superior vena cava to surpass the IVC


Lymphatics: Posterior Body Wall

Pre-aorta nodes
Internal iliac lymph nodes
Common iliac lymph nodes
Lumbar nodes/para aortic on both sides

*Everything runs in sequence (with blood flow) and then everything goes into the cisternic chylii


Lumbar Plexus: Iliohypogastric and Ilio-inguinal Nerves

Iliohypogastric and Ilio-inguinal – L1; run to internal oblique and transversus abdominis


Lumbar Plexus: Genitofemoral Nerve

Genitofemoral L1, L2; runs to cremaster muscle and psoas major


Lumbar Plexus: Lateral Femoral Cutaneous Nerve

Lateral femoral cutaneous L2, L3; passes just inferior to ASIS and goes laterally; does not have a motor component to it, all sensory


Lumbar Plexus: Obturator Nerve

Obturator L2, L3, L4; runs to obturator externus, pectineus, and medial compartment of thigh (adduction)


Lumbar Plexus: Femoral Nerve

Femoral L2, L3, L4; exits through anterior opening under inguinal ligament; runs to iliacus, pectineus, and anterior compartment of thigh (quads)


Lumbar Plexus

1. Iliohypogastric – L1
2. Ilio-inguinal – L1
3. Genitofemoral L1, L2
4. Lateral femoral cutaneous L2, L3
5. Obturator L2, L3, L4
6. Femoral L2, L3, L4

All ventral rami off the spine, whereas dorsal go to deep back
Originate at L1-4 and go through abdomen to lower limb
T12 is NOT part of the lumbar plexus, but of the subcostal plexus


Lumbar Plexus: Cutaneous Innervation

Cutaneous Innervation:
1. Iliohypogastric: L1; medial pelvic and inguinal region
2. Ilioinguinal: nerve passes through inguinal ring to round ligament to labium majora or scrotum
3. Genitofemoral: goes to cremaster muscle