Dr. Sama-ul-Haque

Dr. Rania Gabr

Dr Safaa Ahmed

Describe the origin, termination, course and

branches of the internal iliac artery.

Discuss the origin, site, relations, branches & their

final distribution of the sacral plexus.

Discuss the anatomy of the autonomic supply of the

pelvic organs.

Common iliac artery divides

in front of the sacroiliac joint

into external and internal

iliac arteries.

The Internal Iliac Artery

passes down into the pelvis.

At the upper margin of

greater sciatic foramen it

divides into anterior and

posterior divisions.

The Posterior division supplies:

1- Posterior abdominal wall.

2- Posterior pelvic wall.

3- Gluteal region.

The Anterior division supplies:

1. Pelvic viscera (Except Ovary).

2. Perineum.

3.Gluteal region.

4.Adductor (medial)region of the thigh.

5.The fetus (through the umbilical arteries)

1- Umbilical artery

Gives the superior vesical artery

The distal fibrous part of this

artery becomes the “Medial

Umbilical Ligament”.

2- Obturator artery: pelvic musc. , ms of

med comp of thigh, nutrient arts.

3- Inferior vesical artery (Male)

It supplies, the Prostate, inferior

part of the bladder and the Seminal

Vesicles.

It gives the artery to the Vas

Deferens.

4- Middle rectal artery: supplies: Semin.

vesicle, prostate (vagina), inf part of the

rectum

5- Internal pudendal artery

Leaves pelvis through greater

sciatic foramen

Enters perineum by passing

through lesser sciatic foramen

Enters into pudendal canal with

pudendal nerve

Supplies anal canal musculature,

skin & muscles of perineum.

6- Inferior gluteal artery: pelvic

diaphragm, piriformis, QF, upper

hamstrings,Glut. Max. and Sciatic nerve

7- Uterine artery (Female)

Crosses the ureter superiorly

Ascends in the layers of broad

ligament of uterus

Ends by anastomoses with ovarian

artery

8- Vaginal artery (Female): divides into:

1- vaginal: to vagina

2-inferior vesical : to urinary bladder

1- Iliolumbar artery: ps. Major,

quadr. Lumb, iliacus,and cauda

equina

2- Lateral sacral artery:

piriformis, erector spinae and

skin over, str. In sacral canal

3-Superior gluteal artery:

piriformis, gluteii, tensor fascia

lata

*The pelvis is drained:

•1- Mainly by the internal iliac veins and their tributaries.

•2- Superior rectal veins

•3- Median sacral vein.

•4- Gonadal veins.

•5- Internal vertebral venous plexus

*(A) Somatic:

Sacral plexus

- From Ventral rami of a part of L4 & whole L5 (lumbosacral trunk) + S1,2,3 and most of S4.

- It gives Pudendal nerve to perineum

*(B) Autonomic:

1. Pelvic splanchnic nerves (From S 2 , 3 & 4)

They are the Preganglionic parasympathetic nerves to pelvic viscera & hindgut.

It is formed of:

(a) Pelvic part of sympathetic trunks:

They are the continuation of the abdominal trunks.

They Descend in front of the ala of the sacrum &

terminate inferiorly

in front of the coccyx and form a single ganglion (Ganglion Impar).

(b) Superior & Inferior

Hypogastric plexuses.

2. Sympathetic:

Lies on the posterior pelvic wall in front

of Piriformis muscle.

Formed from:

The anterior rami of 4th & 5th lumbar

nerves

The anterior rami of 1st, 2nd, 3rd & 4th

sacral nerves

4th lumbar nerve joins the 5th lumbar

nerve to form Lumbosacral Trunk

*The pudendal nerve (S2 to 4) supplies most of the perineum.

*It contains motor, sensory (pain and reflex), and postganglionic sympathetic fibers.

* It can be "blocked" medial to the ischial tuberosity, e.g., during labor.

1- The pelvic splanchnic nerves:

*The pelvic splanchnic nerves (S2 to 4) contain parasympathetic preganglionic and sensory fibers.

*They help to form the inferior hypogastric plexus.

Pelvic Part of Autonomic Nervous System

The inferior hypogastric plexuses contain:

*(1) Postganglionic sympathetic fibers;

*(2) Preganglionic parasympathetic fibers, which supply the descending and sigmoid colon and the pelvic viscera.

* (3) Sensory fibers including :

1- Pain fibers (many of which travel in the lumbar splanchnic nerves)

2- Reflex fibers from the bladder (which ascend in the pelvic splanchnic nerves).

*They give origin to the following plexuses, which innervate the pelvic viscera:

1-the rectal plexus;

2-the uterovaginal plexus;

3-the prostatic plexus; and

4-the vesical plexus.

2- Sympathetic fibers

Reach the pelvis by downward

continuations of the 1- sympathetic

trunks and of the 2- aortic plexus.

*The aortic plexus is continued as the

superior hypogastric plexus which

divides in front of the sacrum into right

and left hypogastric nerves.

*The hypogastric nerve descends &

unites with the pelvic splanchnic

nerves to form the right and left

inferior hypogastric plexuses , which

give branches to the pelvic viscera

(e.g., the rectum, bladder, and uterus).