Medical Gross Anatomy: Pelvic Anatomy
Fall 2008
Goals & Objectives
I.
II.
Goal: To understand the general anatomical design of the human pelvis through careful examination of
the following objectives: The student will:
1. Understand the overall composition, morphology, & function of the human pelvis. (Each section
will be described in more detail throughout the objectives. However, it will be necessary to refer
to your slides for some pictures and further clarification):
a. Composition
 Pelvic girdle and floor
 Pelvic organs
 Perineum
 Neurovascular structure
b. Morphology: bowl shaped with skeletal walls, a muscular floor
c. Function: Provide space, support, and protection to viscera
 Distal urinary tract (bladder and urethra)
 Distal digestive tract (rectum and anus
 Reproductive tracts
Goal: To understand the anatomy of the pelvic girdle, in terms of its composition, bony landmarks,
pelvic sex differences, types of fractures, and joints through careful examination of the following
objectives: The student will:
1. Learn the names & characteristics of bones that form the pelvic girdle and os coxae.
a. Composition of the pelvic girdle:
 Os Coxa (2 parts- a right os coxa and a left os coxa): hip or pelvic bone of
irregular shape which consists of 3 bones
 Ileum
 Ischium
 Pubis
b. Sacrum: 5 fused vertebrae
 Sacral canal: longitudinal space and protection for the spinal nerves
 Anterior and posterior sacral foramina: connect with the spinal canal for the spinal
nerves
 Promontory: anterior margin of the body
c. Coccyx “tail bone”- 3 or four fused vertebrae
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2. Be able to determine the anterior, posterior, medial, & lateral surfaces of the os coxae.
a. Lateral surface:
 Acetabulum: cup shaped articular surface for the head of the femur
 Obturator foramen: largest foramen in the body; membrane-covered for muscle
attachment
b. Posterior margin:
 Greater sciatic notch on the superior part of the posterior margin
 Lesser sciatic notch inferior to spine
 Ischial spine separates the notches
 Posterior superior iliac spine (PSIS): terminal point of the iliac crest
 Posterior inferior iliac spine located above the greater notch
 Ischial tuberosity: rough and curved, the “sit” bone, attachment for hamstrings
c. Anterior surface:
 ASIS
 AIIS
 Superior pubic ramus
 Pubic tubercle
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d. Superior Margin:
 Iliac crest: prominent superior ridge
e. Inferior margin:
 Ischial ramus
 Inferior pubic ramus
f. Medial surface:
 Iliac fossa: broad, fan shaped
 Portions of the pelvic brim:
 Arcuate line: lateral pelvic brim
 Pectin pubis: anterolateral pelvic brim
 Pubic crest: anterior brim
3. Learn the names and locations of the bony landmarks of the os coxae and will be able to specify
the ones that can be palpated.
a. PSIS, ASIS, ischial tuberosity, sacrum, iliac crest
4. Learn how to correctly orient the pelvic girdle line in the anatomical position.
a. The pelvic girdle should be tilted posteriorly about 40 degrees downward
b. The ASIS and pubic tubercle line up in the same coronal plane
5. Be able to correctly sex a pelvic girdle through an analysis of observations concerning various
dimorphic features of the pelvis and will know the causes for sexual dimorphism of the human
pelvic girdle.
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a. Female
 Appears less massive, contains less prominent markings and the greater sciatic
notch is wider than the thumb
 Pubic angle is wide (>100 degrees)
 An anatomical compensation for childbirth; need for a birth canal
b. Male
 Appears more massive, contains more prominent markings, greater sciatic notch
is thumb-sized
 The pubic angle is narrow (<80 degrees)
6. Know the morphological classes of the human pelvic inlet and which ones are normally expected
for the male and female.
a. Male: smaller inlet
 Android: heart shaped
 Anthropoid: oval in mid-sagittal direction
b. Female: larger inlet
 Gynecoid: oval in transverse direction
 Platypelloid: more extreme transverse diameter
7. Learn the three measures of pelvic diameters.
a. Transverse: widest, largest diameter (131 mm)
b. Conjugate: promontory to pubic symphysis; smallest diameter (112 mm)
c. Oblique: diagonal (125 mm)
8. Learn the pelvic variations that would increase the probability of the need for a cesarean
delivery.
a. A woman of very small frame might require a cesarean delivery if the physician feels
natural birth could harm her or the baby. The pubic angle is usually the determinant
measurement.
9. Know the locations of probable hip fractures resulting from different forces. (Dr. Terrell only
briefly mentioned this in lecture. I’ll list the most common forms of hip fractures from Wikipedia
for your reading pleasure
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a. Many subtypes of fractures about the hip joint are colloquially known as 'hip fractures'.
Although a true hip fracture involves the joint, the following four proximal femur fractures are
commonly referred to as 'hip fractures'. The differences between them are important because each is
treated differently.
b. Femoral head fracture denotes a fracture involving the femoral head. This is usually the
result of high energy trauma and a dislocation of the hip joint often accompanies this fracture.
c. Femoral neck fracture denotes a fracture adjacent to the femoral head in the neck between
the head and the greater trochanter. These fractures have a propensity to damage the blood supply to
the femoral head, potentially causing avascular necrosis.
d. Intertrochanteric fracture denotes a break in which the fracture line is between the greater
and lesser trochanter on the intertrochanteric line. It is the most common type of 'hip fracture' and
prognosis for bony healing is generally good if the patient is otherwise healthy.
e. Subtrochanteric fracture actually involves the shaft of the femur immediately below the
lesser trochanter and may extend down the shaft of the femur.
10. Learn the name, location, articulation, type of joint, and ligaments for each joint of the pelvic
girdle. Include lumbosacral joint abnormalities.
a. Lumbosacral Joint @ L5-Si
 Movement at two joints
 Zygapophysical joint: synovial planar type between articular processes
 Intervertebral joint: cartilaginous type between bodies of LV & S1 with
intervertebral disk
 Ligaments
 Iliolumbar ligament: LV transverse process to iliac crest
 Lumbosacral ligament: LV transverse process to sacrum
 Anterior longitudinal ligament: lumbar bodies to sacral bodies
b. Sacroiliac Joint: attaches sacrum and os coxae (at the ilium)
 Transmits forces between vertebral column and lower limbs
 Synovial type joint
 Articular surfaces are jagged to interlock which provides more strength
 Ligaments:
 Anterior and posterior sacro-iliac: broad, joint capsule
 Interosseus sacro-iliac: deep and strong; in roughened surfaces of the joint
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c. Pubic symphysis: anterior at the 2 os coxae
 Cartilaginous type joint
 Ligaments:
 Superior and inferior pubic ligaments
 Stretches during childbirth
11. Be able to identify bony structures on a radiograph.
See this website for an interactive “show and tell” of the pelvic radiograph (it also has the same thing for all
parts of the body!!)
http://ect.downstate.edu/courseware/rad-atlas/Pelvis/1PelRad.html
http://ect.downstate.edu/courseware/rad-atlas/index.html
III.
Goal: To understand the anatomy of the pelvic cavity walls and floor through careful examination of
the following objectives: The student will:
1. Understand the morphology, regions, & walls of the pelvic cavity.
a. Muscles of the female pelvis
b. Muscles of the male pelvis
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2. Know the boundaries of the pelvic inlet and outlet of the true pelvis.
a. Pelvic Brim:
 False (greater) pelvis: inferior part of abdomen
 True (lesser) pelvis: forms the pelvic cavity
 Pelvic inlet: circular shaped superior opening
 Boundaries:
 Posterior: sacrum
 Anterior: pubic symphysis
 lateral: distinct bony rim on pelvic bone
 Contents:
 body of vertebra S1projects thru inlet as the sacral
promontory. On each side of this vertebra, wing-like
processes called the alae contribute to the margin of the
pelvic inlet
 fetus passes thru pelvic inlet during childbirth



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Pelvic outlet: diamond shaped inferior opening
Boundaries:
 Anterior: pubic symphysis
 posterior-point of the coccyx
 lateral: ischial tuberosities
Contents: terminal parts of the urinary and gastrointestinal tracts and the
vagina pass through the pelvic outlet
3. Learn the bone, ligaments, & muscles of the lateral walls of the pelvic cavity.
a. Bone: os coxae, sacrum, coccyx
b. Ligaments: enclose sciatic notches to form sciatic foramens and stabilize sacrum with os
coxae
 Sacrospinous ligament: sacrum to ischial spine (function: divides greater and
lesser sciatic foramen)
 Sacrotuberous ligament: sacrum to ischial tuberosity (forms posterior border of
sciatic foramens
c. Muscles:
 Obturator internus: exists through Is. sciatic foramen
 Piriformis: splits greater sciatic foramen into 2 openings
4. Learn the pelvic cavity apertures & their contents.
a. Obturator canal: small slit on the lateral margin of Obturator internus
 Obturator nerve, artery and vein exit to the medial thigh
b. Greater sciatic foramen: superior to piriformis
 superior gluteal nerve, artery, and vein
c. Greater sciatic foramen: inferior to piriformis
 Inferior gluteal nerve, artery, and vein, and sciatic nerve
d. Lesser sciatic foramen
 Obturator internus muscle
 Pudendal nerve and internal pudendal nerve, artery, and vein
5. Understand the structure that covers the floor of the pelvic cavity & outlet and its associated
functions. (Pelvic Diaphragm)
a. Function: to support the pelvic viscera, resist changes in intra-abdominal pressure, and
allow for voluntary control of defecation
b. Composition:
 Coccygeus: triangle shaped to ischial spine; forms and supports the posterior
diaphragm
 Levator ani: bowl-shaped structure that joins in the midline
 Puborectalis: medial- forms the puborectal sling which maintains the
anorectal angle and prevents defecation
 Pubococcygeus- middle
 Iliococcygeus- lateral
 Genital hiatus: a midline gap in anterior levator ani to allow for passage of urethra
and vagina
6. Know the composition of, identify, and function of the pelvic diaphragm, levator ani, and the
genital hiatus.
a. See above
7. Know the major structures that pass through each of the pelvic inlet and outlet.
a. See above
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IV.
8. Learn the types & functions of pelvic fascia and fascial ligaments.
a. Pelvic Fascia Types:
 Parietal: lines inner muscle cavity walls and floor
 Visceral: covers pelvic visceral and vessels
 Endopelvic: filler or packing between viscera
b.
Pelvic Fascial Ligaments: thickening of fascia to provide passive support for the
pelvic organs
 Tendinous arch of pelvic fascia: bilateral band from pubis to sacrum along floor
next to midline
 Pubovesical (puboprostatic) ligament: anterior most; connects bladder
(prostate) to pubis bone
 Sacrogenital (uterosacral): posterior most; connects bladder or cervix and
vagina to sacrum
 Transverse cervical ligament: attaches cervix and vagina to lateral pelvic wall
 Hypogastric sheath: conduit between lateral wall and pelvic viscera for
neurovascular, uteters, vas deferens
Goal: To understand the anatomy of the pelvic cavity viscera through careful examination of the
following objectives: The student will:
1. Learn the ureters’ composition, function, extent, and course through the pelvic cavity.
a. Composition: retroperitoneal muscular tubes (25cm)
b. Function: transport urine via peristaltic constrictions every 25 seconds
c. Extent: only distal half is in the pelvis
 Enter pelvic inlet anterior to the bifurcation of the common iliac
 Course down in pelvic wall
 Posteriolateral sides of bladder
2. Learn the bladder’s composition, function, anatomical surfaces, stabilizing supportive ligaments,
wall structure, and internal structure.
a. Morphology: rounded, 3-sided pyramid shape
b. Surfaces:
 Apex: anteriorly to top of pubic symphysis
 Base: inverted triangle posteroinferiorly
 Internal structure of base:
 Trigone: smooth triangular area
 Ureteric orifices and sphincters: upper corners surround
ureters; constrict during micturation
 Internal urethral orifice and sphincter: encircle urethra;
relaxes during micturation
 Uvula: upward bulge of Trigone from prostate
 Superior surface: balloons upward to the abdomen
 Neck: most inferior part; site of urethra attachment
c. Composition of wall:
 Rugae: distensible folds of mucosa/submucosa
 Detrusor muscle: muscular coat with 3 layers
d. Stabilizing/supportive ligaments:
 Pubioporstatic (pubovesical) ligaments: thickened endoscopic fascia from neck to
pubis bones
 Median umbilical ligament: attaches apex to anterior abdominal wall
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3. Learn the male urethra’s extent and segments.
a. Morphology: 20 cm; bends 2 times
b. Male urethra is divided into four segments
 Preprostatic: 1 cm at the base of the bladder to the prostate; with the internal
urethral sphincter
 Prostatic urethra: 4 cm surrounded by prostate
 Urethral crest: longitudinal midline fold
 Urethral sinus (2): on side of crest
 Receives ejaculatory and prostatic ducts
 Membranous urethra: passes through perineum external urethral sphincter; made
of skeletal muscle (voluntary control)
 Spongy (penile) urethra:
 In root and body of penis (corpus spongiosum)
 Bends 2x at bulb and navicular fossa
 Receives ducts from cowper’s (bulbourethral) glands
 External urethral orifice: a slit at the terminal end
4. Learn the female urethra’s extent, attachment, and why they are more susceptible than men to
urinary tract infections
a. Morphology: short, about 4 cm
b. Attaches to anterior wall of vagina
c. External urethral orifice opens in the vestibule
d. The relatively short length of the urethra in women makes them more susceptible than
men to bladder infection.
5. Learn the rectum’s location, boundaries, transverse folds, and anal canal features.
a. Location: most posterior pelvic organ; anterior to sacrum
b. Boundaries:
 rectosigmoid junction: to sigmoid colon at S3
 anorectal junction: to anal canal at tip of coccyx
 anorectal flexure- 80 degree angle, maintained by puborectalis sling
c. wall structure
 transverse rectal folds (3): valves that retain fecal mass when passing gas
 lacks taeniae coli and omental appendicies
d. anal canal:
 terminal part of GI tract; passes through pelvic floor and perineum
 mucosa folds
 anal columns and sinuses: longitudinal ridges and grooves that release
mucous passages
 internal and external anal sphincters: smooth and skeletal muscle in two layers
 anus (anal aperture): termination of anal canal with perianal skin
6. Understand the general design and comparative anatomy of the male and female reproductive
systems.
General Structure
Male
Female
1. Primary organ
testes
ovaries
2. Tract organs
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vas deferens
ejaculatory duct
urethra
uterine tubes
uterus
vagina
3. Accessory glands
seminal vesicle
prostate
bulbourethral
mammary
paraurethral
vestibular
4. External genitalia
scrotum& penis
vulva
7. Learn the composition of the testes in terms of its protective coat, functional tissues, and
conducting tubules.
a. Protective coats:
 Tunica vaginalis: closed sac of the peritoneum covering anterior aspects and sides
 Tunica albuginea: Connective Tissue capsule-lobes
b. Functional tissues:
 seminiferous tubules- highly coiled (~600): site of meiotic sperm cell formation
 Interstitial cells – between tubules and secrete testosterone
c. Additional tubules:
 rete testis- posterior testes; collecting chamber from seminiferous tubules
 Efferent ductules- (~15)- in posterior capsule, delivers immature sperm to
epididymis.
8. Learn the structures & course of the male reproductive tract.
a. Epidydymis: coiled tube in posterior scrotum, Divided into 3 sections  the head, body,
and tail
b. Function: storage, growth, and maturation of the sperm
c. Ductus (vas) Deferens- long smooth muscular tubes, from tail of epidydymis to
ejaculatory duct. spermatic cord, inguinal canal, deep to inf. epigastric a, crosses ureter,
between bladder & rectum
d. Ejaculatory duct- short and passes through the prostate, formed when vas deferens and
duct of seminal gland join. Empties into prostatic urethra
9. Learn the male accessory organs: their location, morphology, and function. For the prostate
gland, also learn the structures in the prostatic urethra and the impacts of prostatic hypertrophy &
cancer.
a. Seminal vesicles- elongated lobular sacs (5cm)
 Located lateral to vas deferens at the base of the bladder.
 Secrete seminal fluid- alkaline, fructose and prostaglandins- bulk of semen
b. Prostate- large accessory gland,
 Located- posterior to pubic symphysis and anterior to rectum
 Function by secreting milky and acidic to fluid which helps to maintain sperm
health
 Morphology: Conical shaped (3cm x 4cm)
c. 5 lobes of the prostate Seminal colliculus- expanded urethral crest,
 Prostatic utricle- embryological remnant of the vagina
 Openings of ejaculatory ducts- just below utricle- one on each side.
 Urethral sinus- on either side of the colliculus, has openings of the
prostatic ducts.
d. Protective coats- prostatic veins between layers.
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 Prostatic sheath- outer- pelvic fascia and continuous with puboprostatic ligs.
 Prostatic capsule- surface of the gland
e. During prostate cancer prostatic enlargement occurs- nocturia, dysuria, urgency.
 This happens to all elderly males
f. Middle lobe- prostatic urethra and interior to urethra sphincter
g. Bulbourethral (cowper’s) glands (2) - pea-sized paired glands in deep perineal space
 Function: mucosal lubrication of pre-ejaculatory emission
 spongy urethra
10. Learn the location, morphology, …..
a. Ovaries: almond like shape- inferior to pelvic inlet on lateral wall.
b. Ligaments:
 Suspensory ligaments- peritoneum fold and conduit attaches ovary to lateral
pelvic wall and contains
 Ovarian nerve, artery, vein, and lymphatics.
 Ovarian ligaments- to lateral wall of uterus
 Broad ligaments- sheet like fold of peritoneum from lateral pelvic cavity wall to
ovary, uterine tube, and urethra wall.
c. Two functional tissues:
 Cortex: matures and releases ovum (oocyte)
 Medulla: secretes estrogen and progesterone
d. Uterine tubes: extend from uterus superiorly to lateral pelvic cavity
 Segments: Infundibulum- with fimbrae- collect oocyte from ovary
 Ectopic pregnancy: external fertilization
 Ampulla- middle- site of fertilization
 Isthmus- connects to uterus
e. Uterus: tilted anteriorly over the bladder. Anterior to rectum.
 Composition of the uterine wall:
 Peritoneum- peritoneum connective tissue
 Myometrium**- thick smooth muscle tissue, makes up the majority of the uterine
wall
 Endometrium- highly glandular lining of the wall- provides initial nourishment to
embryo
f. Four regions of the uterus:
 Fundus: domed end
 Body: central with uterine cavity
 Isthmus: between body and cervix –narrowing cavity
 Cervix: inferior portion with central canal
 Internal os: opening with uterus
 External os: opening into vagina
g. Fascial ligaments:
 Broad and ovarian ligaments
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V.
 Round ligaments: body of uterus to deep inguinal ring through inguinal ring
through inguinal canal to labium majus
 Pubocervical ligaments: anterior from cervix over bladder to pubis
 Transverse cervical ligament: lateral pelvic wall
 Uterosacral ligament- posterior pelvic wall
h. Recto-uterine (recto-vesical) fold or pouch- lowest portion of abdominopelvic-cavitycollection of fluids
i. Vagina:
 Titled through perineum and pelvic cavity between bladder and rectum.
 Composition of wall: fibromuscular tube with rugae and glands (collapsed)
 Fornix: recess between cervix and vaginal wall
 Vaginal sphincters:
 Rectovesicalis- rectum to lateral vagina to bladder
 Pubovaginalis- pubis to anterior vaginal wall
 Urethrovaginal- encircles
 Bulbospongiosis- in perineum
Goal: To understand the anatomy of the perineum through careful examination of the following
objectives: The student will:
1. Understand the general concept, subdivisions, and boundaries of the perineum.
a. Concept: Series of tissue layers inferior to pelvic floor & attached to pelvic outlet. It’s
the region between the thighs and includes the genitalia.
b. Boundaries:
 pubic symphysis
 ischial tuberosities
 Coccyx; forming a diamond shape.
2. Learn the anal triangle’s boundaries and contents.
a. Boundaries: Line between the ischial tuberosities, the sacrotuberous ligaments, and the
coccyx.
b. Contents:
 anal aperture, external anal sphincter, and the ischio-anal fossae.
3. Learn the strata of the urogenital triangle including the specific locations of the perineal
membrane and superficial & deep perineal pouches.
a. strata going from deep to superficial are: pelvic diaphragm, deep perineal pouch, perineal
membrane, superficial perineal pouch, and the superficial fascia and skin.
4. Learn the contents of the deep perineal pouch including the content differences of muscles &
glands in males & females
a. deep perineal pouch contains the bulbsurethral glad (also known as the cowper’s gland)
in males.
b. Both males and females also have a deep transverse perineal muscle and an external
urethral sphincter.
c. Females also have two additional muscles, the urethrovaginalis sphincter and the
compressor urethrae
5. Learn the contents (erectile tissues, glands, & muscles) of the superficial perineal pouch.
a. Males: it contains the crura of the penis and the bulb of the penis.
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VI.
b. Females it contains the bulbs of vestibule, the greater vestibular glands, and the glands
of the clitoris.
c. Both males and females have ischiocavernosus muscles, bulbospongiosus muscles, and
a superficial transverse perineal muscle
6. Learn the structure of the male’s external genitalia (penis & scrotum)
a. root, shaft, and glands
 the root has the two crura and the bulb of the penis that are attached to the
perineal membrane.
 The shaft is the central part and is supported by the fundiform ligament and the
suspensory ligament of the penis.
 The glans is the cone shaped end of the penis
b. Three columns are present throughout the length of the penis, they are a specialized
cartilage. The dorsal two are the corpora cavernosa and the corpus spongiosum is the
bottom part.
c. Remember the penis is erect in anatomical position for naming.
7. Learn the structure of the female’s external genitalia and the glands of the vestibule.
a. The vulva is the external genitalia and has 4 parts.
 The mons pubis is the superior part covered with hair.
 The labia majora are the lateral skin folds also with hair and attach to the round
ligament of the uterus and cover the bulbosponginosus muscle.
 The labia minora is the medial hairless skin fold that closes and prevents drying.
 The vestibule is the area between the labia minora and contains three things:
 the clitoris (erectile tissue and cutaneous sensitivity)
 the external urethral and vaginal orifices,
 3 glands.
 The three glands are the lesser vestibular glands, the greater
vestibular ducts, and the paraurethral glands (female prostate)
Goal: To understand the anatomy of the pelvic neurovascular structures through careful examination
of the following objectives: The student will:
1. Understand the location, composition, pathway, and function of the sacral plexus.
a. Location: lies anterior to piriformis muscle and is covered with pelvic fascia with
nerves exiting in greater sciatic foramen (described further below)
2. Learn the composition (spinal nerve contribution), pathway, & function of the somatic nerves of
the sacral plexus.
a. Composition: ventral rami of branches from spinal n
 Lumbosacral trunk- L4 & L5
 S1-S4 (together with lumbosacral plexus it forms the sacral plexus)
3. Learn the autonomic trunks, nerves, and plexus that serve the pelvic cavity.
a. Somatic Nerves
 Sciatic n- largest; major n of LL
 Comp: L4-S3
 Exits: inferior to piriformis muscle
 Splits into: Tibial N (L4-S3) and Common Fibular N (L4-S2)—which has
two branches: superficial and deep fibular nerves
 Pudendal N- major nerve of perineum
 Comp: S2-S4
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
Exits: inferior to piriformis muscle, crosses over sacrospinous ligament
and re-enters in lesser sciatic foramen.
 Enters Pudendal canal- medial border of obturator internus muscle—
neurovascular bundle
 Pudendal N in canal divides into:
 Inf rectal N- near entrance of pudendal canal ishoanal fossa
 Motor: ext. anal sphincter and levator ani
 Sensory: skin of anal triangle
 Dorsal N of penis (clitoris)- descends in pudendal canal and in
deep perineal pouch
 Function: primary sensory nerve of the penis or clitoris
 Perineal N- descends in canal and superficial perineal pouch and
divides into:
 Deep perineal N- enters deep perineal pouch
 Motor: muscles of deep and superficial pouches
 Sensory: vestibule and inferior vagina
 Superficial perineal N- in superior perineal pouch
becomes posterior scrotal or labial N (sensory nerves)
b. Pelvic Autonomics
 Sacral paravertebral trunk (2)- 4 ganglia of the sympathetic trunk in pelvic cavity
 Courses over ala and descends medial to ant. Sacral foramina
 Ganglion impar- connects right and left trunks
 Sacral prevertebral trunk- carries sym, parasym, and visceral afferent fibers for
pelvic organs and erectile tissues of perineum
 Superior hypogastric plexus- anterior to L5: distributes sacral prevertebal fibers to
right and left hypogastric nerves, which descend into pelvic cavity and connects
with right and left inferior hypogastric plexus.
 Which is made of right and left hypogastric nerves
 Pelvic splanchnic N- parasym, S2,3, 4
c. Subsidiary plexuses- inn by inferior hypogastric plx:
 Rectal plexus- assoc w/ rectum
 Vesicle plexus- assoc with urinary bladder
 Uterovaginal (prostatic plexus) – erectile tissue of perineum
 Cavernous N- from prostatic plexus erectile tissues of penis
4. Understand the three major vessels that serve the pelvic cavity (internal iliac, gonadal, median
sacral).
a. Internal Iliac Artery:
 Major artery of the pelvic cavity
 Origin: bifurcation of common iliac artery at the lumbosacral joint
 Bifurcation at the pelvic brim to:
 Anterior trunk: supplies the pelvic viscera, perineum, gluteal region,
medial thigh, and placenta
 Branches to:
 Umbilical artery- adjacent to pelvic inlet, ascends in
anterior abdominal wall to umbilicus
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 One branch: superior vesical artery- serves distal
ureter, superior surface of the bladder and the
ductus deferens
 Obturator artery- located below the margin of the pelvic
brim, descends through Obturator foramen with the nerve
above and the vein below; serves medial thigh
compartment
 Inferior vesical (vaginal) artery- inferior bladder, ureter,
seminal vesicle, prostate (vagina), and part of rectum
 Middle rectal artery- serves rectum; anastomoses with
superior rectal artery from the inferior mesenteric artery
and the inferior rectal artery from the internal pudendal
artery
 Internal pudendal artery- main artery of perineum; passes
through greater sciatic foramen inferior to piriformis
muscle and re-enters in lesser sciatic foramen
 Branches to: inferior rectal artery and perineal
artery
 Perineal artery branches to: posterior scrotal
(labial) artery, dorsal artery of penis & deep
artery of penis (clitoris)
 Women only:
 Uterine artery which anastomizes with the ovarian
artery
 Vaginal artery: anastomizes with uterine artery
 Inferior gluteal artery (terminal branch of anterior trunk),
exits in greater sciatic foramen inferior to piriformis to
innervate gluteus maximus
 Posterior trunk: supplies posterior abdominal and pelvic walls as well as
the gluteal region of the hip
 Branches to:
 Iliolumbar artery which ascends above the pelvic rim along
the lumbosacral trunk
 Iliac branch- serves iliac fossa (iliacus m)
 Lumbar branch- lower posterior abdominal wall
 Lateral sacral artery: anterior sacral foramina to serve
sacrum and skin
 Superior gluteal artery- greater sciatic notch, above
piriformis to serve the gluteal region (gluteus medius and
minimus)
b. Gonadal Artery (Testicular or ovarian arteries)
 Testicular artery: accompanies the ductus deferens into the scrotum, where it
supplies the spermatic cord, epididymis, and testis
 Ovarian artery: enters the suspensory ligament of the ovary, supplies the ovary,
and anastomoses with the ovarian branch of the uterine artery
c. Median Sacral Artery: an unpaired artery arising from the posterior aspect of the
abdominal aorta just before its bifurcation
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 Descends in front of the sacrum, supplying the posterior portion of the rectum,
and ends in the coccygeal body, which is a small cellular and vascular mass
located in front of the tip of the coccyx
5. Learn the branches of and the pelvic organs served by the anterior and posterior trunks of the
internal iliac arteries.
a. above
6. Understand the patterns of venous drainage of the pelvic cavity
a. Most veins follow their arteries
b. Internal iliac vein
 Pelvic Plexuses of veins
 Dorsum vein of penis (clitoris)
 Prostatic (vesical) venous plexus- prostate and bladder
 External rectal plexus
c. Non internal iliac veins
 Internal rectal plexus
 Gonadal (testicular or ovarian) vein
 **The left gonadal vein drains to the left renal vein
 **The right gonadal vein drains to the IVC
7. Learn the names of nodes & patterns of lymphatic drainage of the pelvic cavity.
a. Visceral lymphatics
 Internal and external iliac nodes
 Common iliac nodes
 Lateral aortic and preaortic nodes
 Lumbar trunks
 Thoracic duct (forms at T12)
b. Perineum lymphatics
 Superficial penis and scrotum (clitoris and labium major)
 Superficial inguinal nodes
 External iliac nodes
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