Transcript Pelvic Nerves & Vessels Pelvis & Perineum Unit Lecture 5 حيدر جليل األعسم . د
Slide 1
Pelvic Nerves & Vessels
Pelvis & Perineum Unit
Lecture 5
حيدر جليل األعسم.د
Slide 2
Pelvic Nerves
Sacral Plexus
Sacral plexus lies on posterior pelvic wall in front of piriformis
muscle. It is formed from anterior rami of 4th & 5th lumbar
nerves and anterior rami of 1st, 2nd, 3rd & 4th sacral nerves. The
4th lumbar nerve joins the
5th lumbar nerve to form
lumbosacral trunk.
Lumbosacral trunk passes
down into pelvis and joins
sacral nerves as they emerge
from anterior sacral foramina.
Relations
Anteriorly: internal iliac vessels
and their branches, and rectum.
Posteriorly: piriformis muscle.
Slide 3
Pelvic Nerves
Branches of Sacral Plexus
A. Branches to lower limb that leave pelvis through greater sciatic
foramen: Sciatic nerve, Superior gluteal nerve, Inferior gluteal nerve,
Nerve to quadratus femoris muscle, Nerve to obturator internus muscle,
& Posterior cutaneous nerve of thigh.
B. Branches to the pelvis:
Pudendal nerve (S2, 3, and 4),
which leaves pelvis through
greater sciatic foramen & enters
perineum through lesser sciatic
foramen.
Nerves to piriformis muscle
Pelvic splanchnic nerves: forms
sacral part of parasympathetic
system & arise from 2nd, 3rd & 4th
sacral nerves. They are distributed
to the pelvic viscera.
C. Perforating cutaneous nerve:
supplies skin of lower medial part
of buttock
Slide 4
Pelvic Nerves - Lumbar Plexus
Obturator Nerve:
It is a branch of lumbar plexus (L2, 3, and 4), emerges from medial
border of psoas muscle in the abdomen, and accompanies lumbosacral
trunk down into pelvis. It crosses the front of sacroiliac joint and runs
forward on lateral pelvic wall
in angle between internal and
external iliac vessels. On reaching
obturator canal (upper part of
obturator foramen, which is
devoid of obturator membrane),
it splits into anterior and posterior
divisions that pass through the
canal to enter adductor region
of thigh. It supply adductor
muscles and sensory branches
supply parietal peritoneum on
lateral pelvic wall.
Slide 5
Pelvic Nerves - Autonomic Nerves
A. Pelvic Part of Sympathetic Trunk:
Pelvic part of sympathetic trunk is continuous above, behind common
iliac vessels, with abdominal part. It runs down behind rectum on front
of sacrum, medial to anterior sacral foramina. Sympathetic trunk has 4
or 5 segmentally arranged ganglia. Below, the two trunks converge and
finally unite in front of coccyx.
Branches
Gray rami communicantes to sacral and
coccygeal nerves
Fibers that join the hypogastric plexuses
B. Pelvic Splanchnic Nerves
form parasympathetic part of autonomic
nervous system in pelvis. They arise
from 2nd, 3rd & 4th sacral nerves &
synapse in ganglia in inferior hypogastric
plexus or in walls of viscera. Some of its
fibers ascend through hypogastric plexuses
& via aortic plexus to inferior mesenteric
plexus.
Slide 6
Pelvic Nerves - Autonomic Nerves
Superior Hypogastric Plexus
It is situated in front of promontory of sacrum & formed as continuation
of aortic plexus and from branches of 3rd & 4th lumbar sympathetic
ganglia. It contains sympathetic and sacral parasympathetic nerve fibers
and visceral afferent nerve fibers. Superior hypogastric plexus divides
inferiorly to form right and left hypogastric nerves.
Inferior Hypogastric Plexuses
Inferior hypogastric plexuses lie on
each side of rectum, base of
bladder, & vagina. Each plexus is
formed from a hypogastric nerve
(from superior hypogastric plexus)
& from pelvic splanchnic
nerve. It contains postganglionic
sympathetic fibers,
preganglionic & postganglionic
parasympathetic fibers, and
visceral afferent
fibers.
Slide 7
Arteries of the Pelvis
Common Iliac Artery.
Each common iliac artery ends at pelvic inlet in front of sacroiliac joint
by dividing into external and internal iliac arteries
External Iliac Artery
External iliac artery runs along medial
border of psoas muscle, following
pelvic brim, & gives off inferior
epigastric & deep circumflex iliac
branches. It leaves false pelvis by
passing under inguinal ligament to
become femoral artery.
Arteries of the True Pelvis
• Internal iliac artery
• Superior rectal artery (IMA)
• Ovarian artery (Aorta)
• Median sacral artery (Aorta)
Slide 8
Arteries of the Pelvis
Internal Iliac Artery: passes down into pelvis & divides into anterior and
post. divisions. It supplies pelvic viscera, perineum, walls & buttocks.
Branches of Anterior Division
1. Umbilical artery: From its proximal patent
part arises superior vesical artery
(supplies upper portion of bladder)
2. Obturator artery: accompany
obturator nerve to obturator canal.
3. Inferior vesical artery: supplies base
of bladder, prostate & seminal vesicles
in male; also gives artery to vas.
4. Middle rectal artery: arises with
inferior vesical artery. It supplies
muscle of lower rectum & anastomoses
with superior & inferior rectal arteries.
5. Internal pudendal artery: leaves
pelvis through greater sciatic foramen
& enters gluteal region below
piriformis muscle. It then enters perineum by passing through lesser
sciatic foramen. It supplies skin & muscles of perineum & anal canal.
Slide 9
Arteries of the Pelvis
Internal Iliac Artery: passes down into pelvis & divides into anterior and
post. divisions. It supplies pelvic viscera, perineum, walls & buttocks.
Branches of Anterior Division
6. Inferior gluteal artery: leaves pelvis
through greater sciatic foramen below
piriformis muscle. It passes between
1st & 2nd or 2nd & 3rd sacral nerves.
7. Uterine artery: runs medially on
Pelvic floor & crosses ureter superiorly.
It passes above lateral fornix of vagina
to reach uterus. Here, it ascends
between layers of e broad ligament
along the lateral margin of uterus.
It ends by following uterine tube
laterally, where it anastomoses with
ovarian artery. Uterine artery gives
off a vaginal branch.
8. Vaginal artery: takes place of
inferior vesical artery present in male.
It supplies vagina and base of bladder.
Slide 10
Arteries of the Pelvis
Internal Iliac Artery: passes down into pelvis & divides into anterior and
post. divisions. It supplies pelvic viscera, perineum, walls & buttocks.
Branches of Posterior Division:
A. Iliolumbar artery: ascends across
pelvic inlet posterior to external iliac
vessels, psoas, and iliacus muscles.
B. Lateral sacral arteries: descend
in front of sacral plexus, giving off
branches to neighboring structures.
C. Superior gluteal artery: leaves
pelvis through greater sciatic
foramen above piriformis muscle.
Median Sacral Artery
It is a small artery that arises at
bifurcation of aorta. It descends over
anterior surface of sacrum and coccyx.
Slide 11
Arteries of the Pelvis
Superior Rectal Artery
It is a direct continuation of inferior mesenteric artery. It supplies
mucous membrane of rectum and upper half of anal canal.
Ovarian Artery
It arises from abdominal part
of aorta at level of 1st lumbar
vertebra & passes downward
& laterally behind peritoneum.
It crosses external iliac artery
at pelvic inlet & enters suspensory
ligament of ovary. It then passes
into broad ligament & enters
ovary by way of mesovarium.
Slide 12
Veins of the Pelvis
External Iliac Vein
It begins behind inguinal ligament as a continuation of femoral vein. It
runs along medial side of corresponding
artery & joins internal iliac vein to
form common iliac vein. It receives
inferior epigastric & deep
circumflex iliac veins.
Internal Iliac Vein
Internal iliac vein begins by joining
together of tributaries that
correspond to branches of internal
iliac artery. It passes upward in front
of sacroiliac joint and joins external
iliac vein to form common iliac vein.
Median Sacral Veins
Median sacral veins accompany
corresponding artery and end by
joining left common iliac vein
Slide 13
Lymphatics of the Pelvis
Lymph nodes & vessels are
arranged in a chain along
main blood vessels. Nodes
are named
according to blood vessels
with which they are
associated. Thus, there are
external iliac nodes,
internal iliac nodes,
and common iliac nodes.
Slide 14
Thank You
Pelvic Nerves & Vessels
Pelvis & Perineum Unit
Lecture 5
حيدر جليل األعسم.د
Slide 2
Pelvic Nerves
Sacral Plexus
Sacral plexus lies on posterior pelvic wall in front of piriformis
muscle. It is formed from anterior rami of 4th & 5th lumbar
nerves and anterior rami of 1st, 2nd, 3rd & 4th sacral nerves. The
4th lumbar nerve joins the
5th lumbar nerve to form
lumbosacral trunk.
Lumbosacral trunk passes
down into pelvis and joins
sacral nerves as they emerge
from anterior sacral foramina.
Relations
Anteriorly: internal iliac vessels
and their branches, and rectum.
Posteriorly: piriformis muscle.
Slide 3
Pelvic Nerves
Branches of Sacral Plexus
A. Branches to lower limb that leave pelvis through greater sciatic
foramen: Sciatic nerve, Superior gluteal nerve, Inferior gluteal nerve,
Nerve to quadratus femoris muscle, Nerve to obturator internus muscle,
& Posterior cutaneous nerve of thigh.
B. Branches to the pelvis:
Pudendal nerve (S2, 3, and 4),
which leaves pelvis through
greater sciatic foramen & enters
perineum through lesser sciatic
foramen.
Nerves to piriformis muscle
Pelvic splanchnic nerves: forms
sacral part of parasympathetic
system & arise from 2nd, 3rd & 4th
sacral nerves. They are distributed
to the pelvic viscera.
C. Perforating cutaneous nerve:
supplies skin of lower medial part
of buttock
Slide 4
Pelvic Nerves - Lumbar Plexus
Obturator Nerve:
It is a branch of lumbar plexus (L2, 3, and 4), emerges from medial
border of psoas muscle in the abdomen, and accompanies lumbosacral
trunk down into pelvis. It crosses the front of sacroiliac joint and runs
forward on lateral pelvic wall
in angle between internal and
external iliac vessels. On reaching
obturator canal (upper part of
obturator foramen, which is
devoid of obturator membrane),
it splits into anterior and posterior
divisions that pass through the
canal to enter adductor region
of thigh. It supply adductor
muscles and sensory branches
supply parietal peritoneum on
lateral pelvic wall.
Slide 5
Pelvic Nerves - Autonomic Nerves
A. Pelvic Part of Sympathetic Trunk:
Pelvic part of sympathetic trunk is continuous above, behind common
iliac vessels, with abdominal part. It runs down behind rectum on front
of sacrum, medial to anterior sacral foramina. Sympathetic trunk has 4
or 5 segmentally arranged ganglia. Below, the two trunks converge and
finally unite in front of coccyx.
Branches
Gray rami communicantes to sacral and
coccygeal nerves
Fibers that join the hypogastric plexuses
B. Pelvic Splanchnic Nerves
form parasympathetic part of autonomic
nervous system in pelvis. They arise
from 2nd, 3rd & 4th sacral nerves &
synapse in ganglia in inferior hypogastric
plexus or in walls of viscera. Some of its
fibers ascend through hypogastric plexuses
& via aortic plexus to inferior mesenteric
plexus.
Slide 6
Pelvic Nerves - Autonomic Nerves
Superior Hypogastric Plexus
It is situated in front of promontory of sacrum & formed as continuation
of aortic plexus and from branches of 3rd & 4th lumbar sympathetic
ganglia. It contains sympathetic and sacral parasympathetic nerve fibers
and visceral afferent nerve fibers. Superior hypogastric plexus divides
inferiorly to form right and left hypogastric nerves.
Inferior Hypogastric Plexuses
Inferior hypogastric plexuses lie on
each side of rectum, base of
bladder, & vagina. Each plexus is
formed from a hypogastric nerve
(from superior hypogastric plexus)
& from pelvic splanchnic
nerve. It contains postganglionic
sympathetic fibers,
preganglionic & postganglionic
parasympathetic fibers, and
visceral afferent
fibers.
Slide 7
Arteries of the Pelvis
Common Iliac Artery.
Each common iliac artery ends at pelvic inlet in front of sacroiliac joint
by dividing into external and internal iliac arteries
External Iliac Artery
External iliac artery runs along medial
border of psoas muscle, following
pelvic brim, & gives off inferior
epigastric & deep circumflex iliac
branches. It leaves false pelvis by
passing under inguinal ligament to
become femoral artery.
Arteries of the True Pelvis
• Internal iliac artery
• Superior rectal artery (IMA)
• Ovarian artery (Aorta)
• Median sacral artery (Aorta)
Slide 8
Arteries of the Pelvis
Internal Iliac Artery: passes down into pelvis & divides into anterior and
post. divisions. It supplies pelvic viscera, perineum, walls & buttocks.
Branches of Anterior Division
1. Umbilical artery: From its proximal patent
part arises superior vesical artery
(supplies upper portion of bladder)
2. Obturator artery: accompany
obturator nerve to obturator canal.
3. Inferior vesical artery: supplies base
of bladder, prostate & seminal vesicles
in male; also gives artery to vas.
4. Middle rectal artery: arises with
inferior vesical artery. It supplies
muscle of lower rectum & anastomoses
with superior & inferior rectal arteries.
5. Internal pudendal artery: leaves
pelvis through greater sciatic foramen
& enters gluteal region below
piriformis muscle. It then enters perineum by passing through lesser
sciatic foramen. It supplies skin & muscles of perineum & anal canal.
Slide 9
Arteries of the Pelvis
Internal Iliac Artery: passes down into pelvis & divides into anterior and
post. divisions. It supplies pelvic viscera, perineum, walls & buttocks.
Branches of Anterior Division
6. Inferior gluteal artery: leaves pelvis
through greater sciatic foramen below
piriformis muscle. It passes between
1st & 2nd or 2nd & 3rd sacral nerves.
7. Uterine artery: runs medially on
Pelvic floor & crosses ureter superiorly.
It passes above lateral fornix of vagina
to reach uterus. Here, it ascends
between layers of e broad ligament
along the lateral margin of uterus.
It ends by following uterine tube
laterally, where it anastomoses with
ovarian artery. Uterine artery gives
off a vaginal branch.
8. Vaginal artery: takes place of
inferior vesical artery present in male.
It supplies vagina and base of bladder.
Slide 10
Arteries of the Pelvis
Internal Iliac Artery: passes down into pelvis & divides into anterior and
post. divisions. It supplies pelvic viscera, perineum, walls & buttocks.
Branches of Posterior Division:
A. Iliolumbar artery: ascends across
pelvic inlet posterior to external iliac
vessels, psoas, and iliacus muscles.
B. Lateral sacral arteries: descend
in front of sacral plexus, giving off
branches to neighboring structures.
C. Superior gluteal artery: leaves
pelvis through greater sciatic
foramen above piriformis muscle.
Median Sacral Artery
It is a small artery that arises at
bifurcation of aorta. It descends over
anterior surface of sacrum and coccyx.
Slide 11
Arteries of the Pelvis
Superior Rectal Artery
It is a direct continuation of inferior mesenteric artery. It supplies
mucous membrane of rectum and upper half of anal canal.
Ovarian Artery
It arises from abdominal part
of aorta at level of 1st lumbar
vertebra & passes downward
& laterally behind peritoneum.
It crosses external iliac artery
at pelvic inlet & enters suspensory
ligament of ovary. It then passes
into broad ligament & enters
ovary by way of mesovarium.
Slide 12
Veins of the Pelvis
External Iliac Vein
It begins behind inguinal ligament as a continuation of femoral vein. It
runs along medial side of corresponding
artery & joins internal iliac vein to
form common iliac vein. It receives
inferior epigastric & deep
circumflex iliac veins.
Internal Iliac Vein
Internal iliac vein begins by joining
together of tributaries that
correspond to branches of internal
iliac artery. It passes upward in front
of sacroiliac joint and joins external
iliac vein to form common iliac vein.
Median Sacral Veins
Median sacral veins accompany
corresponding artery and end by
joining left common iliac vein
Slide 13
Lymphatics of the Pelvis
Lymph nodes & vessels are
arranged in a chain along
main blood vessels. Nodes
are named
according to blood vessels
with which they are
associated. Thus, there are
external iliac nodes,
internal iliac nodes,
and common iliac nodes.
Slide 14
Thank You