Urinary system notes for undergraduate medical students

1. Ureters
Urinary bladder
Dr.Prajkta Kulkarni
Assistant Professor
Rachanasharir(Anatomy)
Tilak Ayurved Mahavidyalaya,Pune
email- prajktakulkarni2005@gmail.com

2. URETERS
A pair of muscular tubes ,convey urine
From the kidneys to the urinary bladder.
•narrow ,cylindrical tubes.
•Length- 25-30 cm,diameter -3 mm
•3 parts –
•Pelvis of ureter,abdominal and pelvic parts
1.Pelvis –funnel shaped dilatation of upper part of uereter.
formed by union of major calyces within renal sinus..

3. Pelvis is continuous with abdominal part of the
Ureter at level of lower end of corresponding
Kidney.
-capacity – 5-7 ml
2. Abdominal part-
passes downwards and slightly medially
beneath peritoneum of posterior abdominal
wall and enters pelvic cavity by crossing the
bifurcation of common iliac artery.

4. Relations –
Behind-
1)psoas major and its fascia.
2)Genitofemoral nerve
3)Tip of transverse processes of all lumbar vertebrae
In front –
Right ureter – parietal peritoneum,right gonadal vessels,2 and 3rd part of duodenum
right colic and ileo-colic branches of superior mesentric vessels,
root of mesentry,terminal part of ileum
Left ureter- parietal peritoneum,left gonadal vessels,left colic and sigmoid branches
of inferior mesentric vessels,apex of inverted V of sigmoid mesocolon.

5. 3) Pelvic part –
a)passes downwards beneath peritoneum of lateral pelvic wall.
along anterior margin of greater sciatic notch.reaches level of ischial spine.
b)From ischial spine,passes forwards and medially through extraperitoneal tissue
above levator ani,reaches superolateral angle of base of bladder 5 cm away from
opposite ureter.
c)Finally pierces musculature of bladder ,undergoes oblique submucosal course
medially and downwards through bladder wall and opens into the interior of bladder.
Ureteric openings are -2.5 cm apart-when bladder is empty
5 cm apart- when bladder is distended
Relations-posterior-(from before backwards)-
-internal iliac artery and its anterior division
-internal iliac vein
-lumbosacral trunk
-sacroiliac joint

6. Medially- covered with peritoneum
Laterally- from above downwards-
obliterated umbilical artery ,obturator nerve and vessels,internal vesical
artery ,middle rectal artery,in females-uterine and vaginal arteries
2nd part of ureter-
In male-
Below and laterally- levator ani and its fascia
Above and medially –covered by peritoneum.
At the lateral angle of base of bladder –
Above and medially – crossed by vas deferens
Below – upper end of seminal vesicle

7. In female –
Above-
1.Lower attached margin of broad ligament of uterus.
2.Uterine artery- it crosses above and in front of ureter from lateral to medial side.
Below-
1.Mackenrodt’s ligament
2.Lateral fornix of vagina
3.Levator ani
Medially – 1.supravaginal part of cervix uteri
2. anterior vaginal wall
Laterally – uterine artery

8. 3rd part of ureter –
in interior of bladder where there is a ureteric fold of mucous
Membrane which extends upwards and laterally from corresponding ureteric
Orifice .
•Factors preventing reflux of urine from the bladder to ureters-
1.Oblique direction of intra –vesical part of ureter.
2 obliquity of ureter is maintained by construction of trigonal muscle,which acts
from posterior wall of proximal urethra.
3.Peristalsis of ureteral muscles –passes downwards at rate of 2-5 times/min.
4.normally,luminal pressure of upper ureter -15cm of water
luminal pressure of lower ureter- 30 cm of water
Intravesical pressure (of 400 ml urine)- 10 cm of water

9. INTERNAL STRUCTURE-
3 coats-fibrous ,muscular,mucous
1.Fibrous –consists of elastic fibres, continuous with fibrous capsule of kidney
in the floor of renal sinus.
2. Muscular – 2layers of myocytes
in upper 2/3 – inner longitudinal and outer circular
In lower 1/3 – 3 layers – outer longitudinal,middle circular,inner longitudinal
circular muscles help to squeeze urine from ducts of Bellini to minor calyces.
Outer 2 layers continuous with detrusor muscle of bladder.
Inner longitudinal muscle of ureter forms triangular sheet (muscle of Bell)-blends
with mucous membrane of internal trigone .

10. •Mucous membrane – lined by transitional epithelium and thrown into 6
longitudinal folds when ureter is empty.
3 Constrictions-
1.At pelvi-ureteric region
2.At pelvic brim
3.At point where ureter pierces bladder wall ,narrowest of all other parts.
Blood supply- branches from renal artery,aorta,testicular,common iliac,vesical and
uterine vessels.
Venous drainage- veins accompanying above vessels
Nerve supply- renal ,aortic,superior and inferior hypogastric plexuses

11. Lymphatics –
upper part- para aortic
intermediate part- common iliac
lower part- internal and external nodes
Applied anatomy-
1.Renal colic
2.Ureteric stone

12. URINARY BLADDER
•Synonyme- vesicae
•Hollow,saclike structure
•Reservoir of urine
•Location-
In children – abdominopelvic
In adult – pelvic- when empty
bladder neck lies just above plane of lower border of symphysis pubis
Abdomino-pelvic – when distended
Shape – tetrahedral- empty
ovoid- distended

14. Capacity – 120-320 ml
mean- 220 ml
Micturition takes place – when bladder contains 280 ml urine
Tolerance upto – 500 ml
Above this ,pain starts due to bladder tension and reflux contractions.
T11-L2,S2-S4-supply- bladder as well as same segment of spinal cord.
So pain is experienced in th lower part of the abdominal wall,perineum,
In males-penis

15. FEATURES –
Empty bladder has –
Base ,neck,apex,superior surface and
2 inferolateral surfaces.
1.base/fundus-
triangular,directed backwards and
Downwards.(top portion)
In females-in close relation with aneterior wall of vagina.
In males-in close relation with rectum.
But upper part is separated from rectum by rectovesical pouch of peritoneum.
Below that seminal vesicles and deferent ducts separate the 2 viscera.

16. 2.Neck –
lowest region of bladder and most fixed part.lies 3-4 cm behind lower part of
symphysis pubis.
In males- neck is in direct continuity with base of bladder.
In females- neck surrounds upper part of urethra.
3.Apex-
directed forwards towards upper part of symphysis pubis.
-from it,urachus (median umbilical ligament)is continued upwards on posterior
Surface of anterior abdominal wall to the umbilicus.
4 superior surface-
triangular,bounded on each side by a lateral border,runs from apex to entrance
Of ureter into bladder and by a posterior border (line joining entrances of ureters into
Bladder.

17. In males-
This surface is completely covered with peritoneum ,which is continued behind into
Rectovesical pouch.It is in contact with sigmoid colon and terminal coils of small
Intestine.
In females-
Peritoneum covers large part except area related to supravaginal part of uterine
cervix.
5.Inferolateral surface-
devoid of peritoneum.
In males- related to pubis,puboprostatic ligament,levator ani,obturator internus.
In females –same as above,pubovesical ligament

18. LIGAMENTS-
True-
1.Lateral true ligament- from side of bladder to arch of pelvic fascia.
2.Lateral puboprostatic ligament- anerior end of pelvic fascia to upper part of
prostatic sheath.
3.Medial puboprostatic ligament- from back of pubis to prostatic sheath.
in females –as pubovesical ligament
4.Median umbilical ligament
False –
Median umbilical fold-peritoneal folds which do not support.

19. CAPACITY-
Mean- 220 ml
Beyond 220 ml-desire to micturate
Upto 500 ml-tolerable
Beyond it- painful.
BLOOD SUPPLY-
Superior and inferior vesical arteries,obturator and inferior gluteal arteries
VENOUS DRAINAGE-
Vesical venous plexus- internal iliac veins
LYMPHATIC DRAINAGE-external iliac nodes
NERVE SUPPLY-vesical plexus of nerves

20. INTERIOR-
muscular- detrusor muscle
Outer longitudinal,middle circular,inner longitudinal
Around the opening of urethra,circular fibres form internal sphincters,below those
are external urethral sphincters.
Small triangular area at base of bladder is called as trigone of bladder.At the apex of
Trigone is located internal urethral orifice.Ureters open at posterolateral angles
Of the trigone.
Uvula vesicae- slight elevation on trigone posterior to urethral orifice.
APPLIED ANATOMY-
1.Ectopia vesicae
2.Rupture of bladder
3.Cystoscopy