L2: GROSS ANATOMY OF KIDNEYS & URETER
KIDNEY/ RENAL/ NEPHRON
A pair of excretory organ
A retroperitoneal organ lies in the posterior abdominal wall on either side of the
vertebral column
Occupies epigastric, hypochondriac, lumbar & umbilical region
Extent: upper border of T12 to the centre of L3
Function: remove waste products of metabolism and excess water & salt, maintain pH
TRANSPYLORIC PLANE (L1) passes through the upper part of the hilus of
R.kidney and the lower part of the hilus of L.kidney
(11 × 6 × 3), 150gm (male), 135gm (female)
Poles: upper pole broader and related to adrenal gland & lower pole pointed
Borders:
i. Lateral border: convex
ii. Medial border: concave, have hilum with renal vein, artery, and
pelvis (VAP)
Surfaces: The anterior surface is irregular, and the posterior surface is flat
Coverings:
i. Fibrous (true) capsule: thin membrane
ii. Perirenal fat: a layer of adipose tissue, thicker at the lateral border
iii. Renal fascia (false capsule): fibro areolar sheath surrounding the kidney
iv. Pararenal fat: fatty tissue, more in post part, lat aspect and lower pole
Anterior relation:
i. Right kidney: rt suprarenal gland, liver, 2nd part of duodenum, SI
ii. Left kidney: lt suprarenal gland, spleen, stomach, pancreas, splenic AV
Posterior relation: diaphragm, psoas major, quadratus lumborum, transverse abdominis,
med&lat arcuate ligaments, subcostal AVN, RK to 12 th rib and LK to 11th & 12th ribs
Macroscopic structure
i. Kidney proper:
Outer cortex
- Appears pale yellow with a granular texture, located below the renal capsule
- Consists of cortical arches and renal columns
- Cortical arches: between the base of pyramids and the kidney surface
- Renal column (columns of Bertini): extends between renal pyramids
, Inner medulla
- Made up of 8-18 pale, striated conical masses called renal pyramids (pyramids of
Malpighi)
- The apex of pyramids forms nipple-like projections (renal papillae) opening into
minor calyx
- Base of pyramids towards the cortex
ii. Renal sinus
- Space within the kidney, opens at the medial border through the hilum
- Lined by renal capsule and filled by renal vein, artery, pelvis (VAP)
- Renal pelvis divides into 2/3 major calyces & major into 10/12 minor calyces
Microscopic structure
- Each kidney has about 1 million uriniferous tubules
- Each uriniferous tubules consist of a secretory part & collecting tubules
Arterial supply:
i. Renal artery - branch of abdominal aorta at L2
ii. Accessory renal artery – present in 30% of inidividuals
iii. At hilus, renal artery divides into ant&post division, then into segmental A
Venous drainage: renal vein draining into IVC
Lymphatic drainage: lateral aortic nodes
Nerve supply: renal plexus composed of sym¶, sym fibers from T10-L1 are vasomotor
KIDNEY/ RENAL/ NEPHRON
A pair of excretory organ
A retroperitoneal organ lies in the posterior abdominal wall on either side of the
vertebral column
Occupies epigastric, hypochondriac, lumbar & umbilical region
Extent: upper border of T12 to the centre of L3
Function: remove waste products of metabolism and excess water & salt, maintain pH
TRANSPYLORIC PLANE (L1) passes through the upper part of the hilus of
R.kidney and the lower part of the hilus of L.kidney
(11 × 6 × 3), 150gm (male), 135gm (female)
Poles: upper pole broader and related to adrenal gland & lower pole pointed
Borders:
i. Lateral border: convex
ii. Medial border: concave, have hilum with renal vein, artery, and
pelvis (VAP)
Surfaces: The anterior surface is irregular, and the posterior surface is flat
Coverings:
i. Fibrous (true) capsule: thin membrane
ii. Perirenal fat: a layer of adipose tissue, thicker at the lateral border
iii. Renal fascia (false capsule): fibro areolar sheath surrounding the kidney
iv. Pararenal fat: fatty tissue, more in post part, lat aspect and lower pole
Anterior relation:
i. Right kidney: rt suprarenal gland, liver, 2nd part of duodenum, SI
ii. Left kidney: lt suprarenal gland, spleen, stomach, pancreas, splenic AV
Posterior relation: diaphragm, psoas major, quadratus lumborum, transverse abdominis,
med&lat arcuate ligaments, subcostal AVN, RK to 12 th rib and LK to 11th & 12th ribs
Macroscopic structure
i. Kidney proper:
Outer cortex
- Appears pale yellow with a granular texture, located below the renal capsule
- Consists of cortical arches and renal columns
- Cortical arches: between the base of pyramids and the kidney surface
- Renal column (columns of Bertini): extends between renal pyramids
, Inner medulla
- Made up of 8-18 pale, striated conical masses called renal pyramids (pyramids of
Malpighi)
- The apex of pyramids forms nipple-like projections (renal papillae) opening into
minor calyx
- Base of pyramids towards the cortex
ii. Renal sinus
- Space within the kidney, opens at the medial border through the hilum
- Lined by renal capsule and filled by renal vein, artery, pelvis (VAP)
- Renal pelvis divides into 2/3 major calyces & major into 10/12 minor calyces
Microscopic structure
- Each kidney has about 1 million uriniferous tubules
- Each uriniferous tubules consist of a secretory part & collecting tubules
Arterial supply:
i. Renal artery - branch of abdominal aorta at L2
ii. Accessory renal artery – present in 30% of inidividuals
iii. At hilus, renal artery divides into ant&post division, then into segmental A
Venous drainage: renal vein draining into IVC
Lymphatic drainage: lateral aortic nodes
Nerve supply: renal plexus composed of sym¶, sym fibers from T10-L1 are vasomotor
