The Urinary System

1. The Urinary System 山东大学医学院 解剖教研室 李振华

2. 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)

3. 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

4. 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.

5. 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

6. 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

7. 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

8. 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

9. 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

10. 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

11. Relationships of kidneys • 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

12. 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)

13. 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

15. 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

16. 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)

17. Stone in ureter

18. 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

19. Bladder 膀胱 General features • Pyramidal in shape when empty, having • Apex, • Fundus • Body of bladder • Neck

20. 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.

21. 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

22. Urethra尿道 Female urethra • Relatively short (about 5cm long), wide and straight • Opens into vaginal vestibule

23. 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

24. 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.

25. 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

26. 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 • Obturatorn.闭孔神经 • Genitofemoral n. 生殖股神经

27. 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

28. 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

29. 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