T1 Anatomy of Posterior Abdominal Wall & Urinary System

Diaphragm - median arcuate ligament formed by

right crus (L1-3) and left crus (L1-2)

IVC passes through

Caval opening (T8)

Aorta passes through

Aortic hiatus (T12)

Esophagus passes through

Esophageal hiatus (T10)

Diaphragm blood supply

Inferior phrenic arteries

Diaphragm innervation

Phrenic nerve (C3-5)

Quadratus lumborum - function

Fixes rib 12 during inhalation

Quadratus lumborum - innervation

T12 subcostal nerve

Psoas major - function

Flexes hip joint

Psoas major - innervation

L1-L3

Psoas minor - function

Flexes lumbar vertebral column

Psoas minor - innervation

L2-L4

Iliacus - function

Flexes and stabilizes hip joint

Iliacus - innervation

Femoral nerve (L2-L4)

Iliohypogastric nerve - motor

Internal oblique, transversus abdominis

Iliohypogastric nerve - sensory

Posterolateral gluteal region, pubic skin

Ilioinguinal nerve - motor

Internal oblique, transversus abdominis

Ilioinguinal nerve - sensory

Upper medial thigh, root of penis/scrotum, mons pubis, labium majus

Genital branch of genitofemoral nerve - motor

Cremaster muscle

genitofemoral nerve - sensory

Anterior scrotum, mons pubis, upper anterior thigh

Obturator nerve - motor

Medial thigh muscles

Obturator nerve - sensory

Medial thigh skin

Femoral nerve - motor

Anterior thigh muscles

Femoral nerve - sensory

Anterior thigh and medial leg skin

Lateral cutaneous nerve of thigh - sensory

Anterolateral thigh

Celiac trunk supplies

Foregut, spleen

Superior mesenteric artery supplies

Midgut

Inferior mesenteric artery supplies

Hindgut

Right gonadal and suprarenal veins drain into

IVC

Left gonadal and suprarenal veins drain into

Left renal vein

Lymphatic drainage

Para-aortic (lateral aortic) nodes > cisterna chyli > thoracic duct

Right kidney - location

Lower than left kidney, below liver

Left kidney - location

Below diaphragm

Kidney hilum (anterior to posterior)

Renal vein > renal artery > renal pelvis

Kidney blood supply

Renal artery (T12-L3), segmental arteries

Kidney venous drainage

right branches > IVC, left gonadal and left suprarenal > left renal > IVC

Adrenal cortex produces

Corticosteroids, androgens, aldosterone

Adrenal medulla produces

Epinephrine, norepinephrine

Ureter constriction sites

Ureteropelvic junction, crossing of iliac artery, ureterovesical junction

Male urethra parts

Prostatic, membranous, spongy (penile)

Detrusor muscle - function

Contracts to expel urine

Internal urethral sphincter - type

Involuntary (smooth muscle)

External urethral sphincter - type

Voluntary (skeletal muscle)

Female urethra - location

Anterior to vagina

Sympathetic innervation of kidneys

Renal, celiac, mesenteric plexuses via splanchnic nerves

Parasympathetic innervation of kidneys

Vagus nerve

Sympathetic action on bladder

Relaxes detrusor, contracts sphincter

Parasympathetic action on bladder

Contracts detrusor, relaxes sphincter

Pudendal nerve - function

Controls external urethral sphincter

Greater splanchnic nerve (T5-T9) - synapses in

Celiac and superior mesenteric ganglia

Lesser splanchnic nerve (T10-T11) - synapses in

Aorticorenal and superior mesenteric ganglia

Least splanchnic nerve (T12) - synapses in

Aorticorenal and inferior mesenteric ganglia

Lumbar splanchnic nerves (L1-L2) - synapses in

Inferior mesenteric and superior hypogastric plexus

Superior hypogastric plexus - location

At aortic bifurcation

Inferior hypogastric plexus - location

Pelvic wall