The Urinary System

山东大学医学院 解剖教研室

李振华

Composition Two kidney － form

urine Two ureter － conduct

urine from kidneys to bladder

Bladder － receives and stores urine

Urethra － conducts urine from bladder to exterior of body (discharged)

Kidney 肾General features Bean shaped, reddish-

brown organs Superior extremity － broad

and thin Inferior extremity － narrow

and thick Anterior surface － convex Posterior surface － flat Lateral border － convex

Medial border － concave Renal hilum 肾门－ a

vertical slit on the medial border of kidney, the structures which enter and leave the renal hilum is called renal pedicle 肾蒂 , including the renal vein, renal artery, renal pelvis, lymphatic vessels and nerves

Order of structures in the renal pedicle from anterior to posterior － V. A. P.; from superior to inferior － A. V. P.

Renal sinus 肾窦

－ which is the renal hilum leads into a space within the kidney, the rental sinus is occupied by the renal vessels, minor renal calices, major renal calices, renal pelvis and some adipose tissue

Structure of the kidney Renal cortex 肾皮质

renal columns 肾柱

Renal medulla 肾髓质 Renal pyramids 肾锥体 : 15 ～

20 Renal papilla 肾乳头

Papillary foramina 乳头孔

Minor renal calices 肾小盏

(7 － 8) Major real calices 肾大盏 (2

～ 3) Renal pelvis 肾盂

Coverings Fibrous capsule 纤

维囊 － a strong fibrous capsule which strips easily from a normal kidney surface but adheres firmly to an organ that has been inflamed

Position Lie behind peritoneum

one on each side of the vertebral column high up on the post abdominal wall, upper pole nearer to media plan than lower pole

Fatty renal capsule 脂肪囊 － a thick adipose connective tissue capsule, surrounds the fibrous capsule. It acts as a shock absorber to protect the kidney from jolting and jarring

Renal fascia 肾筋膜－ on outside, surrounds both the kidney and suprarenal gland, holding these organs in place

Left kidney lies at the level from the lower border of T11 to L2; the 12th rib is behind its middle part of the post surface

Right kidney lies slightly lower than the left kidney, at the level from the lower border of T12 to L3; the 12th rib is behind its upper part of the post surface

Renal hilum at the level of L1, is about 5cm from the posterior median line

Renal region － the area between 12th rib and the lateral margin of erector spinae

Superiorly － superarenal gland Posteriorly

Three muscles Diaphragm (pleural cavity), Psoas major Quadratus lumborum

Three nerves Subcostal Iliohypogastric Ilioinguinal

Medial Left kidney － abdominal aorta Right kidney － inferior ceva

vana

Relationships of kidneys

Anteriorly Left kidney

Stomach (superior), Pancreas (middle), Loops of intestine and

left colic flexure (inferiorly)

Right kidney Right lobe of liver

(superior) Right colic flexure

(inferior) Descending part of

duodenum (medially)

Renal segments The kidney is divided into

five vascular segments and each is supplied by a branch of the renal artery; between the segments there is no anastomosis.

The segments are Superior segment Superior anterior segment Inferior anterior segment Inferior segment Posterior segment

Ureters 输尿管 Muscular tube, about 25cm

long Three parts

Abdominal part － descend on the psoas major behind the peritoneum

Pelvic part － in females, passes 2cm lateral to the neck of uterus and lies below the uterine artery

Intramural part － passes obliquely through the bladder wall for 2cm long

Three constrictions At the pelvoureteric

junction Where it crosses the

pelvic inlet and iliac vessels

Where it pierces the bladder wall obliquely (at intramural part)

Stone in ureter

Relation of abdominal part of ureter

Anterior to left ureter Descending part of duodenum Right colic vesseles Iliocolic vesseles Testicular vesseles Terminal part of ileum

Right to left ureter Cecum Vermiform appendix

Anterior to left ureter Duodenojejunal flexure Left colic vesseles Testicular vesseles

Bladder 膀胱

General features Pyramidal in shape

when empty, having Apex, Fundus Body of bladder Neck

Interior of bladder Mucous membrane folded,

except for trigone of bladder Trigone of bladder 膀胱三角

－ smooth triangular area at inner surface of the funds of bladder, formed by internal urethral orifice anteriorly and two ureteric orifices laerally, in this area absents submucosal layer, where the mucous membrane is firmly adherent to the muscular coat, and is always smooth

Interureteric fold 输尿管间襞 － muscular elevation, between ureteric orifices.

Location In the adult, it lies in the

lesser pelvis, behind the pubic symphysis, in front of seminal vesicle, ampulla ductus deferentis and rectum in the male, and in front of uterus and vagina in the female.

In the young child the empty bladder projects above the pelvic inlet

Urethra 尿道

Female urethra Relatively short (about

5cm long), wide and straight

Opens into vaginal vestibule

Retroperitoneal space and contents

Position － it lies between the parietal peritoneum and transvers fascia of the posterior abdominal wall, from diaphragm to promontory of sacrum, continuation with extraperitoneal fascia.

Contents － kidney, suprarenal gland, ureter, abdominal aorta, inferior vena cava, nervers and lymphatics, loose connective tissue

Suprarenal gland 肾上腺Shape and position Right is pyramidal in shape, left one

semilunar in shape, consisting of out cortex and inner medulla

Located retroperitoneally, superomedial to superior poles of each kidney, enclose with the kidney by the renal fascia

Blood supply Arteries

Superior suprarenal a. Middle suprarenal a. Inferior suprarenal a.

Venous drainge Right suprarenal v. drains into inferior

vena cava Left suprarenal v. joins left renal v.

Nervers of abdomen Lumbar plexus 腰丛

Formation: formed by anterior rami of L1-L3, a part of anterior rami of T12and L4

Position: lies within substance of psoas major

Branches Iliohypogastric n. 髂腹下神经

Supplies lower part of anterior abdominal wall

Ilioinguinal n. 髂腹股沟神经 Passes through inguinal canal to supply skin of the groin and scrotum

Lateral femoral cutaneous 股外侧皮神经

Femoral n. 股神经

Obturator n. 闭孔神经 Genitofemoral n. 生殖股神经

Lumbar sympathetic trunk 腰交感干

Made up of paired chains with four to five lumbar ganglia anterolateral to vertebral column

Enters abdomen via the diaphragm and as a continuation of he thoracic part

Passes inferiorly behind common iliac vessels and terminations by joining to form unpaired ganglion impar, anterior to sacrum

Relations of abdominal aorta Anteriorly (from above

downward) Pancreas Ascending part of

duodenum Radix of mesentery

Posteriorly Upper four lumber

vertebrae On its right

Inferior vena cava On its left

Left lumbar sympathetic trunk

Relations of inferior vena cava Anteriorly (cranially to caudally)

Liver Head of pancreas Horizontal part of duodenum Right testicular (or ovarian) a. Radix of mesentery

Posteriorly Right crus of diaphragm Upper four lumber vertebrae Left sympathetic trunk Parietal branches of abdominal aorta

On its right Psoas major Right kidney Right suprarenal gland

On its left Abdominal aorta