Anatomy Of The Urinary System Flashcards
List the functions of the kidneys and urinary tract
- excretion
- regulation: fluid volume, ionic components, acid-base balance + homeostasis
- endocrine: synthesis of renin, erythropoietin, prostaglandins
- metabolism: activate vit D + catabolism of insulin, parathyroid hormone, calcitonin
Describe the anatomical location of the kidneys
- retroperitoneum on the posterior abdominal wall either side of the vertebral column
- between T12-L3 vertebrae
What is a small kidney (<8cm) a sign of?
Chronic kidney disease
Losing the cortex
What vertebral level is the hilum at?
L1
What layers surround the kidney?
- renal capsule
- perirenal fat
- renal fascia - holds fat + kidneys in place
- pararenal fat
What parts of the nephron are in the cortex?
- bowman’s capsule
- PCT
- DCT
What part of the nephron is in the medulla?
- Loop of Henlé
- collecting duct
Outline the drainage of the kidneys
- collecting duct
- papillae
- minor calyces
- major calyces
- renal pelvis
- ureter
What are the two types of nephrons?
- Cortical: short LoH
- Juxtamedullary: long LoH
Outline the blood supply to the kidneys from the aorta to the inferior vena cava
- aorta
- renal artery
- segmental artery
- interlobar artery
- arcuate artery
- interlobular artery
- Afferent arteriole
- golmerulus
- Efferent arteriole
- peritubular capillaries OR vasa recta
- interlobular vein
- arcuate vein
- interlobar vein
- segmental vein
- renal vein
- IVC
Describe the ureters
- smooth muscle fibres that propel urine to urinary bladder
- 25-30cm
- retroperitoneal
- lateral to tips of transverse processes
What is the most common area of ureteric injury?
Near the pelvic brim
What bony landmarks can be used in an X-ray to approximate the course of the ureter?
- L1 at the hilium
- runs lateral to the tip of lumbar transverse processes
- crosses and descends into pelvis at sacroiliac joint
- kink towards bladder at ischial spine
What prevents urine from moving back up the ureter?
Increased pressure closes the vesicoureteral junction
What allows the bladder to contract and expand?
Muscular folds called rugae
Describe the bladder
- detrusor muscle
- muscular folds called rugae
- lined with transitional epithelium - urothelium
- can hold 750ml
Where does an empty bladder rest in men and women?
- Men: in front of rectum
- Women: in front of vagina, uterus + rectum
What urethral sphincter is under voluntary control?
External urethral sphincter
What are the male urethral divisions?
- prostatic urethra
- membranous urethra
- bulbous urethra
- penile/spongy urethra
Explain why the left kidney is higher than the right kidney
The right kidney is pushed down by the liver
What is the role of the renal pelvis in the kidney?
Urine passes from the major calyces to the renal pelvis before it drains into the ureter to go to the bladder for storage
What is the renal hilum and what does it do?
- a deep cut which marks the dial margins of the kidneys
- renal vessels + the ureter enter/exit the kidney through it
What is the arterial supply to the kidneys?
right and left renal arteries from the abdominal aorta
What is the junction between the renal pelvis and the ureter called?
Pelviureteric junction
What is the junction between the ureter and the bladder called?
Vesicouretic junction
What is the venous drainage of the kidneys
left and right renal veins drain into the inferior vena cava
Describe the lymphatic drainage of the kidneys
Lateral aortic nodes
What is the anatomical location of the prostatic urethra?
Traverses the prostate
What is the anatomical location of the membranous urethra?
From the apex of the prostate to the bulb of the penis
Is the left or right renal vein longer?
Why?
Left renal vein
IVC is to the right of the aorta
Further distance to travel
Is the left or right renal artery longer?
Why?
Right renal artery
Aorta is on the left of the IVC
Further to travel
What is the renal pyramid?
Cone shaped kidney tissues
(Just the medulla | not the cortex)
What are the renal lobes?
Triangular portion of kidney consisting of the renal pyramid + the renal cortex above it
What are the renal columns?
Space in between the renal pyramids
Describe the course of the ureter until it enters the bladder referencing abdominal muscles + major vessels
- arise form pelvis of each kidney
- descend on top of psoas major to reach brim of pelvis
- crosses in front of common iliac arteries
- runs postero-inferiorly on lateral walls of pelvis
- curves antero-medially to enter bladder
What vertebral level would you find the right kidney?
T12 - L3
What vertebral level would you find the left kidney?
T11/12 - L2/3
