Notes on the anatomy of the urinary system

Transpyloric plane
 Imaginary line across L1 level.
 Crosses the renal hilum.
 Hilum --> opening where nerve and blood vessels enter the kidney. It’s also the opening
where the ureter leaves the kidney.

Posterior relations
 9th and 1thh ribs ---->
fracture can damage
kidneys.
 Psoas major muscle.
 Quadratus lumborum.
 Transversus abdominis.
 Muscles are packed by
the thoracolumbar
fascia

Renal fat and fascia
 Outside the renal capsule --------> extraperitoneal fat called perinephric fat (perirenal
fat).
 Protection.
 Insulation of kidneys ----> maintenance of heat.

Ureters
 Transport urine from kidneys to the bladder.
 Continuous with the renal pelvis.
 Renal pelvis ----> ureter at the ureteropelvic junction.
 Muscular tubes ----> transport urine via peristalsis.

The point in which ureters can become blocked by stones
 Ureteropelvic junction.
 Pelvic inlet.
 Entrance into the bladder.

Vasculature of the kidney
 Left and right upper and lower renal
arteries.
 Left and Right Renal veins. Left renal
vein is longer and it passes below the
superior mesenteric artery.
 Left renal vein can become entrapped
between the abdominal aorta and the
superior mesenteric artery ------->
nutcracker syndrome ----> puts
pressure on the gonadal vein --->
kidney damage + changes in gonads.